Franks Workshop: Electrical Plans

[Frank Pellow]

This thread is a spin-off from the thread entitled "Frank's Workshop Construction Project" (http://www.sawmillcreek.org/showthread.php?t=7769).

I plan to do all of the wiring except the actual hookup of the 60 amp auxiliary box to my 200 amp house service. I am reasonably experienced in house wiring but have never done anything other than a clothes drier with 220 volts.

I am attaching a diagram with my current plans and solicit suggestions. For easy reference purposes, I will repeat my shop layout diagram as well so that folks can see what I plan to do with the electricity.

[Jim Becker]

Looks good, Frank. My only concern would be with your lighting. Be sure you have things arranged so you get good, even light distribution, particularly at night when you will not have the benefit of the skylights. Much of your lighting appears to be pushed out to the edges and unless those incandescents in the middle something special, you may get a lot of shadows.

[Dick Parr]

Frank, you note that you have 4-220 volt outlets, but only show 3? Two in the floor and one in the wall by the drill press. I wish I had put at least 1 220 volt outlet on each wall for future tools down the road. I have 2 in each side wall but none on front or back wall. Wish I had one on the front wall so that I didn't have to run a 220 extension cord to my planner that sits up front of the shop.

Just a thought while you are in the thinking stage. Put at least one in each wall so that it will make it easier to arrange tools at a later date if you add any.

[JayStPeter]

Real good job planning there. I agree w/Jim on the lights. I would also put another 220 outlet on the long wall. Just in case you want to move stuff around. You won't have to run a 220 extension cord all the way across the shop.

Jay

[Steven Wilson]

Nice layout job but I would nix the incadecent bulbs and run some flourencent fixtures down the middle. You might also consider running appropriate sized conduit and wire for your 220V circuits. Once you've finally layed out the machines then you can locate the outlets and wire up the circuits. For simplicity you might want to use 10ga wire and then you can easily change from a 20a to a 30a circuit by just changing the breaker.

[Bob_Hammond]

You might want some 110 outlets in the middle of the shop. I have an overhead reel that I use this a lot for things like the palm sander or the electric drill. You could probably put floor outlets instead.

Bob

[Larry Browning]

Frank,
I would second the ceiling outlets. Think about over the workbench with a retractable reel. And If you are planning a ceiling mounted air cleaner, an outlet for that is real handy. As others have said you should put quite a bit of thought into the lighting. My main shop area is 30x30 and I have 4 rows of 8' T8 florescent fixtures. This provides good even lighting with hardly any shadows. Do not skimp on the fixtures! I spent over $800 on light fixtures and have never regreted it for 1 second.

Larry

[Frank Pellow]

Thanks, I have received lots of good advice, just as I hoped that I would.

• Jim, Jay, Steven, and Larry, I will look at my lighting again. In particular, I except that there will now be a row of florescent tubes near the ridge and a reduction in incandescent lights.

• Dick, there are four 220 volt outlets -three for tools and one for the dust collector.

• Dick and Jay, I will add at least one more 220 volt outlet. That will be in the middle of the back wall. I will think about more but at the cost of one circuit each, I think that I will probably stop at 5 outlets.

• Bob and Larry, I will probably put in an overhead 110 outlet with a retractable reel over the proposed location of my woodworking bench and another over the proposed location of my assembly table.

• Steven, I can't imagine that I will ever require a 30 amp circuit, but I will give your suggestion re conduit some thought.

[Jim Becker]

Frank, unless you invest in the more expensive tubes that have the proper coloring for light output, don't eliminate most of the incandescents as they add "warmth" to the lighting. The more common tubes are way too cold and "blue". Regardless, do buy quality fixtures, however, with low-temp ballasts. Those inexpensive "shop lights" will cause you all kind of trouble and you'll be spending good money after bad. And make sure that all your fixtures either have guards or that you put the tubes in the plastic protectors and use coated bulbs in the incandescent fixtures. It's amazing how much damage a long board can do in the blink of an eye!

[Chris Padilla]

Frank,

I attached a pic with the lights I have in my garage (circled in white). Personally, I can't stand flourescent bulbs due to the flicker I sometimes see and the hum I sometimes hear.

I have these halogen lights I picked up from Northern Tool: http://tinyurl.com/2t48m

I see the cost has gone up. I paid $20/light about 8 months ago.

One word of warning, whomever packages these lights often forgets to tighten anything down. I had to dismantle every light to retighten stuff...not difficult but time consuming. I complained to NT about some missing hardware in one package...they just sent me a whole new light! I guess it was cheaper that way for them...so I got 5 lights for $80 plus shipping.

The light these suckers produce is wonderful. One bad thing about them...they get hot...very hot. However, they are pretty far above my head so that isn't too big a deal.

[JayStPeter]

Frank,

Why a circuit per 220V outlet? Is that code?

If so, you can get rid of one of the floor ones and just make a 220V power strip to run your TS/jointer/planer. You wouldn't be able to run them at the same time, but you leave some panel expansion.

Jay

BTW, I like your efficient use of dust ports around the TS/jointer/planer.

[JayStPeter]

Chris,

Good to see you keep all the shop towels nice clean and folded. ;)

Jay

[Chris Padilla]

I need a new pic, you guys are too observant! :rolleyes:

:D

[Rob Russell]

Frank,

I've got several comments.

1) Remember that you need to maintain 3' deep x 3' wide x 6.5' tall clear "working space" in front of your panel. You may not have anything permanent sticking into that space. That space may not be used as "storage". These are NEC requirements and your inspector should red tag the installation if it's violated.

I'd try to find a place other than the corner where the panel will get buried in stuff. The wall just to the right of the double doors looks like a good possibility.

2) Install a 100 amp subpanel, not a 60 amp. It won't cost that much more and the work is the same. You're just running a larger set of conductors from your main service panel out to the workshop. I'd install a 40 slot panel. Again, the cost difference just isn't that huge and it means you won't run out of slots for breakers.

3) On your 120v outlets, consider running multiwire circuits. That would mean you could "splitwire" the receptacles and give you access to a 15 (or 20) amp circuit on the top outlet and a second 15 (or 20) amp circuit on the bottom outlet. It means you can plug a 15 amp router and shop vac into that one receptacle and you're pulling from 2 different halves of the circuit. You'd need to use 2-pole breakers if you have different hot legs on the same yoke. I would anyway. The 2-pole breakers will eat up panel space and is another reason to use the 40 slot panel.

4) Use a SquareD "QO" series panel - best quality.

5) I'd move the thermostat away from the gas heater on basic principle of not wanting it misread based on proximity to the heater.

Rob

[Chris Padilla]

3) On your 120v outlets, consider running multiwire circuits. That would mean you could "splitwire" the receptacles and give you access to a 15 (or 20) amp circuit on the top outlet and a second 15 (or 20) amp circuit on the bottom outlet. It means you can plug a 15 amp router and shop vac into that one receptacle and you're pulling from 2 different halves of the circuit. You'd need to use 2-pole breakers if you have different hot legs on the same yoke. I would anyway. The 2-pole breakers will eat up panel space and is another reason to use the 40 slot panel.

Rob
Rob,

I am trying to understand this better. For the two-circuited 120 V outlet (forgive my non-electrician's terms), you can run a hot black and a hot red to the outlet and return on the (single) white. In the breaker box, you would have the 2-pole breaker with 1 red and 1 black going into it. So, it is like a 240 V circuit but split off to get 2 120 V circuits. Is this correct?

Sorry, I don't follow what "different hot legs on the same yoke" means. What is the yoke referring to exactly?

I've had ideas to run a double outlet (4 120 V plug-ins, 4 separate circuits, if you will) but returning on a single white doesn't seem right.

Please correct my thinking here. Thanks! :)

[Rob Russell]

Rob,

I am trying to understand this better. For the two-circuited 120 V outlet (forgive my non-electrician's terms), you can run a hot black and a hot red to the outlet and return on the (single) white. In the breaker box, you would have the 2-pole breaker with 1 red and 1 black going into it. So, it is like a 240 V circuit but split off to get 2 120 V circuits. Is this correct?

Sorry, I don't follow what "different hot legs on the same yoke" means. What is the yoke referring to exactly?

I've had ideas to run a double outlet (4 120 V plug-ins, 4 separate circuits, if you will) but returning on a single white doesn't seem right.

Please correct my thinking here. Thanks! :)

Chris,

Your description of a multiwire circuit is basically correct. If you wanted to install a 2-gang box with 2 receptacles, you'd have a choice of splitwiring with 2 circuits or splitwiring with 4 circuits. Each pair of hots would need a neutral. You couldn't run 4 hots and 1 neutral - you'd run the danger of overloading the neutral and that wouldn't meet code (see below for why - see if you can figure it out).

A yoke is the metal strap that, for example, a receptacle is assembled on and that mounts to the box. The way the code is written, if you splitwire a receptacle so you have black on top, red on the bottom sharing a common neutral, you need to have a 2-pole common disconnect breaker. If you had 2 receptacles, 1 fed by the black, the other fed by the red - you could use individual breakers without even a common disconnect. I wouldn't do the latter because you run the danger of having 1 of the 2 legs hot when you go into the box. I'd use the 2-pole breaker for any multiwire circuit. That way you can splitwire receptacles or boxes and you're guaranteed that everything in the box is dead when you're in there working on it.

The reason you can share a neutral is that the 2 busses of your panel are actually fed from a single phase. The 2 busses are 180 degrees out of phase. Think of 2 sine waves that are exactly out of phase - that's what your house AC would look like on an ocilloscope (sp?). If you have a multiwire circuit with 10 amps drawn on the black hot leg and 7 amps on the red hot leg, you'll have 3 amps of current flowing back through the common neutral. That's why 240 volt motors don't need a neutral. The 2 legs exactly offset each other and there is no current to flow back through a neutral. Given this example - see if you can figure out why you couldn't have 4 hots and 1 neutral. :)

FYI - it's code legal to have a 2-pole breaker that's used for both 240 volt and 120 volt loads on the same circuit. An electric dryer or range with the built-in lights are perfect examples of this; a spa that has 240v pump motors and 120v underwater lights and control relays is another example.

Frank - one comment I forgot before. If you can wire in a dryer - you can install a subpanel. There are a few additional things to worry about with the subpanel, but you can save yourself a lot of money if you want to run the wiring and install it yourself. It looks like a big branch circuit in your main panel. Holler if you decide to go the DIY route and we can talk about the things to install a subpanel.

Rob

[Tony Laros]

Frank, to make the wiring of the 15 or so 110 volt outlets a bit faster and cheaper I would use 12/3 and run it all around the shop. Connect alternating outlets to black and the next one to red, etc. Mar the unused hots together in each box. You'd still feed from 2 individual breakers, one for black and the second for red, but if you tripped a breaker every other outlet would still work. Also, consider using 3 way switches for your lights, since you have 2 entry/exit doors. I regret not doing this in my shop, and it seems to happen often that I shut off the lights and lock up and then having to go back to the other part of the shop to shut off a bank of lights. Also, why switch the GFI?

[Frank Pellow]

WOW, a lot more good advice and even a picture since I responded yesterday.

Here are my responses to the new postings:

• Jim, in spite of your advice, I am going to reduce the number of incandescent ceiling fixtures. I like the light that is produced by the C-50 fluorescent tubes. It is much better than the light produced by the old "warm white" tubes. I will still use incandescent focused task lighting but those lights will be portable.

• Jim, unless the cost is prohibitive, I do plan to purchase low temperature ballasts.

• Chris, I prefer fluorescent to halogen and my shot ceiling will not be as high as yours. I tried suspended halogen lights in my garage/workshop when I lived in Seattle (for 7 years). The light was OK, but I did not like the heat.

Also, like Jay, I am impressed by your pile of towels -much nicer than my bag of rags.

• Jay, you asked " Why a circuit per 220V outlet? Is that code? ". I thought that it was part of the Ontario code, but now I am not so sure. My "bible" for most of the wiring that I am doing is the "Ontario Electrical Code Simplified (Residential Wiring)", a 140 page book by P. S. Knight. I thought that I had seen this restriction in the book but searched for about half an hour last evening and could not find it.

• Rob, thanks for your warning for the need for space around the sub-panel. I had no idea that there was a rule about this. Of course the NEC regulations do not apply here, but there are a similar set of rules that do apply (for example, 1 metre in front of the box).

• Rob, I will consider the 100 amp sub-panel.

• Rob, with all the outlets I planning to have, I doubt that I will need split receptacles. But, there was lots of detailed information in your two different notes with wiring details and I will need to study the information more in order to fully comprehend it.

• Rob, thanks for your recommendation re a SquareD "QO" series panel. I have my doubts that this panel is available, or even allowed, within Canada but I will check.

• What was I thinking when I placed the thermostat close to the gas heater? Even my wife noticed this mistake.

• Tony, re your suggestion to "use 12/3 and run it all around the shop". This is a good idea that I will consider. For now, I will leave my plans as is, but might employ your when it comes time to purchase and do the wiring.

[Frank Pellow]

There is one more thing that I meant to say. In Rob's last post he said:

Frank - one comment I forgot before. If you can wire in a dryer - you can install a subpanel. There are a few additional things to worry about with the subpanel, but you can save yourself a lot of money if you want to run the wiring and install it yourself. It looks like a big branch circuit in your main panel. Holler if you decide to go the DIY route and we can talk about the things to install a subpanel.

Thanks for the offer Ron. I am planning to run the wire myself and I am even planning to dig a 20 metre trench between the two panels myself. But, my insurance company seemed a whole lot happier with the fact that I planned to do do most of my own wiring when I told them that I would have a real electritian hook up the sub-panel.

I will probably do some of the wiring in the sub-panel myself and, when I do, Rob I might very well take you up on your kind offer.

[JayStPeter]

" Why a circuit per 220V outlet? Is that code? ".[/I] I thought that it was part of the Ontario code, but now I am not so sure. My "bible" for most of the wiring that I am doing is the "Ontario Electrical Code Simplified (Residential Wiring)", a 140 page book by P. S. Knight. I thought that I had seen this restriction in the book but searched for about half an hour last evening and could not find it.


Frank - I had the same problem reviewing code here. I found some specific info on dedicated Dryer, Appliance and AC Unit 220V wiring. But, there was nothing about more "general use" or multi-outlet 220V wiring. I guess most people don't really have a bunch of things that run off 220. I finally had to ask some electricians. Two electricians verified that it is fine. That's enough for me.

Jay

[Rob Russell]

Frank,

Tony Laros’ comment about alternating receptacles on circuits is just another way of wiring a multiwire circuit. The only “cost” to run a multiwire circuit is the difference between 12/3 and 12/2 NM cable (“Romex”) . The benefit is you have a whole second circuit to pull power from. Whether you chose to splitwire receptacles or use Tony’s scheme of alternating receptacles between the 2 hot legs – this is a really cheap way to give yourself better power access around the shop.

I forgot to mention this before, but I heartily agree with the comments about giving yourself more 240v receptacles. I’d put in 1 on the left wall by the workbenches, 3 along the long back wall and 1 in the back corner near the sheet goods cart. Each of these really doesn’t need to be a separate circuit.

I would install “receptacle stations” with 120v and 240v power at each. Run (2) 10/2 + (1) 12/3 “Romex” around the shop and install a pair of 240 receptacles + (1) multiwire 120v receptacle at each station. This would give you access to 2 separate 240v circuits and 2 separate 120v circuits pretty much anywhere on those other shop walls and will only use 6 slots in your panel.

Conduit is a good idea, but you need to be careful about derating. If you have 4 – 6 current-carrying conductors in a conduit, the derating factor is 80%. #12 THHN has an ampacity for these purposes of 25 amps, so the derating drops that to 20 amps. #10 THHN has an ampacity of 35 amps which drops to 28 amps, or not quite enough for a 30 amp circuit. If you ran conduit, you could run (4) #12 + EGC now and then replace a pair of the #12 with #8 for a 30 amp machine if that becomes a need in the future.

You might consider a single incandescent light by each door on a motion sensor. That way you can walk into the shop with your hands full, even in the dark, and know that you’ll be able to see. I’d also consider putting in one of those self-contained battery backup emergency exit lights so, if the power goes out when you’re out there at night, you have some light in the shop.

The SquareD “QO” series panel is a standard panel you should be able to find at your local Home Depot (and Toronto has 7 of them). Just get the QO series, not the “Homeline” series.

In terms of doing the wiring yourself vs. having a licensed electrician do it, I’d say the important thing is that the work is done neatly, to the applicable codes for your area and passes inspection. You told your insurance company that you were planning to have an electrician do the hookup – well plans can change. You may find it difficult to hire an electrician for as small a job as just hooking up the subpanel.

Talk with the AHJ (Authority Having Jurisdiction) - at least that’s the NEC term for the inspector in the USA – and see if they have a problem with you doing the work. They will want to inspect the trench with the conduit in it before you backfill to ensure the trench is deep enough. The NEC would specify 18” deep. Check to see what your local code is. You will need expansion sleeves on either end where the conduit comes up out of the ground end enters a building. This allows the conduit to move with frost heaves. I’d run (3) #2 THWN [black, red, white] + (1) #6 THWN [green for EGC]. Ask your AHJ if they require a separate GES (Grounding Electrode System) for your shop. Ask your AHJ if they require an outside disconnect for the shop (that’s a fire requirement in some areas that allows firemen to kill power to a building before entering in the event of a fire).

I’ll stop writing now before you get tired of reading. :D

Rob

[Frank Pellow]

Rob, your notes are amazing. It is like having my own electrical authority on call. Thanks very very much for taking the time to share your knowledge. My responses are interspersed within the text that I copied from your last posting.

Tony Laros’ comment about alternating receptacles on circuits is just another way of wiring a multiwire circuit. The only “cost” to run a multiwire circuit is the difference between 12/3 and 12/2 NM cable (“Romex”) . The benefit is you have a whole second circuit to pull power from. Whether you chose to splitwire receptacles or use Tony’s scheme of alternating receptacles between the 2 hot legs – this is a really cheap way to give yourself better power access around the shop.

Frank's response: OK, I will plan to run 12/3 cable. I have not yet figured out exactly how I will use it but, I assume that that can wait.

I forgot to mention this before, but I heartily agree with the comments about giving yourself more 240v receptacles. I’d put in 1 on the left wall by the workbenches, 3 along the long back wall and 1 in the back corner near the sheet goods cart. Each of these really doesn’t need to be a separate circuit.
I would install “receptacle stations” with 120v and 240v power at each. Run (2) 10/2 + (1) 12/3 “Romex” around the shop and install a pair of 240 receptacles + (1) multiwire 120v receptacle at each station. This would give you access to 2 separate 240v circuits and 2 separate 120v circuits pretty much anywhere on those other shop walls and will only use 6 slots in your panel.

Frank's response: I still don't think that I will need any more than five 240v receptacles. So, I am not planning to take your advice on this. I am still trying to get a definitive word on whether each 240v outlet must be on its own circuit in Ontario. If separate circuits are not required, I will probably run cable that will allow me to add outlets if I later on find that I need them

Conduit is a good idea, but you need to be careful about derating. If you have 4 – 6 current-carrying conductors in a conduit, the derating factor is 80%. #12 THHN has an ampacity for these purposes of 25 amps, so the derating drops that to 20 amps. #10 THHN has an ampacity of 35 amps which drops to 28 amps, or not quite enough for a 30 amp circuit. If you ran conduit, you could run (4) #12 + EGC now and then replace a pair of the #12 with #8 for a 30 amp machine if that becomes a need in the future.

Frank's response: My current thought is that I will not run conduit.

You might consider a single incandescent light by each door on a motion sensor. That way you can walk into the shop with your hands full, even in the dark, and know that you’ll be able to see.

Frank's response: I have already revised the layout so that there is an incandescent light by each door. Putting them of a motion detector is a good idea. It might even be good for security. By the way, I am having the alarm system that is on my house extended to the shop,

I’d also consider putting in one of those self-contained battery backup emergency exit lights so, if the power goes out when you’re out there at night, you have some light in the shop.

Frank's response: We don't lose power very often, so I don't think I will do this.

The SquareD “QO” series panel is a standard panel you should be able to find at your local Home Depot (and Toronto has 7 of them). Just get the QO series, not the “Homeline” series.

Frank's response: I found a Square D 100 amp panel at Home Depot today when I was pricing things. I did notice which series it was. By the way, it was the most expensive of about half a dozen brands.

In terms of doing the wiring yourself vs. having a licensed electrician do it, I’d say the important thing is that the work is done neatly, to the applicable codes for your area and passes inspection. You told your insurance company that you were planning to have an electrician do the hookup – well plans can change. You may find it difficult to hire an electrician for as small a job as just hooking up the subpanel.

Frank's response: I talked to an electrician who is friend of a friend and who owes me a favour. He has tentatively agreed to do the hookup and whatever other work I may want him to do. In addition, he says that he can probably get me good prices on material.

Talk with the AHJ (Authority Having Jurisdiction) - at least that’s the NEC term for the inspector in the USA – and see if they have a problem with you doing the work.

Frank's response: The AHJ is OK with me doing ALL the work.

They will want to inspect the trench with the conduit in it before you backfill to ensure the trench is deep enough. The NEC would specify 18” deep. Check to see what your local code is.

Frank's response: Here it has to be 450 mm deep (with is slightly less than 18 inches).

You will need expansion sleeves on either end where the conduit comes up out of the ground end enters a building. This allows the conduit to move with frost heaves.

Frank's response: OK

I’d run (3) #2 THWN [black, red, white] + (1) #6 THWN [green for EGC].

Frank's response: WOW, #2 wire. I was planning on running # 6. Number 6 is expensive enough; I wonder what number 2 will cost and where I can get it.

Ask your AHJ if they require a separate GES (Grounding Electrode System) for your shop. Ask your AHJ if they require an outside disconnect for the shop (that’s a fire requirement in some areas that allows firemen to kill power to a building before entering in the event of a fire).

Frank's response: OK. I certainly would not have thought of either of these things. They are not mentioned in the Ontario Electrical Code Simplified book so I doubt that they will be needed.

I’ll stop writing now before you get tired of reading.

Frank's response: I am definitely not tired of reading. But, I am somewhat overwhelmed.

[Jim Becker]

Frank, regardless of actual code requirements , it's a good idea to put your DC on a separate circuit from your tools. Same goes for a compressor if you have one, regardless of 120v or 240v. These two tools are the ones that will likely be running when other tools are in use. Unless prohibited by your local regulations, the rest could really be on the same circuit since you're an individual woodworker and it is unlikely you'd be running two at once. (other than the DC and compressor, of course) The advantage of sprinkling more of them around is flexibilty if you get involved in a large project or stumble upon a really good deal on a new or used tool!:D

If you do combine any 240v outlets into a single circuit, use a large J-box to branch to the outlets. Don't daisy chain them...there isn't a whole lot of room in the boxes and the recepticles, if you use twist locks, can only handle one wire for each pole including ground. Unless you use really big boxes for those recepticals, you'd not have room for pigtails anyway. Using the J-Box also makes it a piece of cake to add or relocate a 240v recepticle in the future if you need to do so...something that I've taken advantage of several times in four years!

[Frank Pellow]

Frank, regardless of actual code requirements , it's a good idea to put your DC on a separate circuit from your tools. Same goes for a compressor if you have one, regardless of 120v or 240v. These two tools are the ones that will likely be running when other tools are in use. Unless prohibited by your local regulations, the rest could really be on the same circuit since you're an individual woodworker and it is unlikely you'd be running two at once. (other than the DC and compressor, of course) The advantage of sprinkling more of them around is flexibilty if you get involved in a large project or stumble upon a really good deal on a new or used tool!:D

If you do combine any 240v outlets into a single circuit, use a large J-box to branch to the outlets. Don't daisy chain them...there isn't a whole lot of room in the boxes and the recepticles, if you use twist locks, can only handle one wire for each pole including ground. Unless you use really big boxes for those recepticals, you'd not have room for pigtails anyway. Using the J-Box also makes it a piece of cake to add or relocate a 240v recepticle in the future if you need to do so...something that I've taken advantage of several times in four years!

Yes, I will definately have the Dust Control Unit on it's own circuit. I don't have a compressor nor any plans to get one. There are too many other goodies on my want list to even think about a compressor.

Jim, just like Rob, you are giving me homework. Now I need to find out what a J-Box is.

[Jim Becker]

Yes Jim, just like Rob, you are giving me homework. Now I need to find out what a J-Box is.

My pleasure to make you work harder! :D

A "J-Box" is a junction box...basically a metal or plastic box large enough for you to bring together the quantity of wires you need to splice. There are usually some code requirements relative to size, but for your purpose, it will not need to be something really big. I usually use a deep, two-position metal box for this purpose with a blank metal cover. If you use a metal box for this or any of your outlets, your ground must also tie to the box as well as to any outlets or switches contained within. This is true for the j-box, too...it has to be grounded if metal.

[Rob Russell]

Rob, your notes are amazing. It is like having my own electrical authority on call. Thanks very very much for taking the time to share your knowledge. My responses are interspersed within the text that I copied from your last posting.


Blush. Thanks and you're welcome.



OK, I will plan to run 12/3 cable. I have not yet figured out exactly how I will use it but, I assume that that can wait.


Definitely.



I found a Square D 100 amp panel at Home Depot today ... it was the most expensive of about half a dozen brands.


Yeah, they're not cheap. They are top quality.



I talked to an electrician who is friend of a friend and who owes me a favour. He has tentatively agreed to do the hookup and whatever other work I may want him to do. In addition, he says that he can probably get me good prices on material.


That's great. He will know about any odd local codes you need to follow. FYI, in our area, if you are going to do any of the electrical work - you must pull the permit. Your rules may be different.



WOW, #2 wire. I was planning on running # 6. Number 6 is expensive enough; I wonder what number 2 will cost and where I can get it.


You said you need to dig a 20 meter trench. I figured a 75' run of wire, although it could be a longer run. #3 THWN has an ampacity rating of 100 amps, but at that distance voltage drop starts to become a factor. Upsizing to #2 THWN will reduce the voltage drop. FYI, #6 at 25 meters and a 60 amp load at 120v will have a voltage drop of about 3.6%, which is above the NEC recommendation. I know you wouldn't have a 60 amp 120v load, but think of 120v loads you're running off of that subpanel which is 75 feet away from your main service panel. You'd really only be able to run a 50 amp subpanel through #6.

Another option, if you don't want to go with conduit, is direct burial aluminum cable. It would need to be 1/0 aluminum, but that could cost less than the THWN. Check with your electrician friend. Conduit is considered a "wet location" (it's underground), so anything you run needs to be wet-location rated (eg, THWN vs. THHN). I'd check with your Home Depot or your electrician friend.

Here's a link to a voltage drop calculator. There are a whole bunch of neat things on this website. Voltage Drop Calculator (http://www.jhlarson.com/ind_tables/calc_voltdrop.htm)

I also agree with Jim Becker's comment about running dedicated circuits for the compressor and dust collector.

Rob

[Frank Pellow]

One clarification. I am not planning on running conduit within the shop but I am planning to run the wirte that connects the main box to the shop sub-panel underground through PVC pipe. I guess some people consider that to be conduit.

[Frank Pellow]

I won't claim to have absorbed and processed all the advise that I have recieved, but I have used the input to make several major revisions to my electrical layout plans. The new version is attached.

[Rob Russell]

Frank,

One thought on your DC wiring ...

A pair of 3-way switches by the doors is probably not where you'd be located to conveniently turn your DC on and off, especially over by your sanding tools.

With 3 dust ports, you will need blast gates. If you choose to make your own blast gates, you can make a remote-control system for your DC for under $100, for under $50 if you're patient (maybe even under $50 Cdn). By remote-controlled, I mean "open a blast gate and the DC turns on - close all the gates and the DC shuts off". If you don't want to mess with the gates, a set of "maintained contact, normally open" pushbuttons in small boxes would work too (pull it out to start, push in to stop).

You'd need a 24VAC transformer (under $10), some mini-pushbutton switches from Radio Shack ($5), a contactor ($20) and box to put the contactor in ($10). You'd run doorbell wire or similar to your blast gates.

An alternate solution is the true remote controlled "Long Ranger" style on/off setup where you'd clip a remote to your belt.

If you're interested in more info about how to wire these, holler.

Rob

[Frank Pellow]

Frank,

One thought on your DC wiring ...

A pair of 3-way switches by the doors is probably not where you'd be located to conveniently turn your DC on and off, especially over by your sanding tools.

With 3 dust ports, you will need blast gates. If you choose to make your own blast gates, you can make a remote-control system for your DC for under $100, for under $50 if you're patient (maybe even under $50 Cdn). By remote-controlled, I mean "open a blast gate and the DC turns on - close all the gates and the DC shuts off". If you don't want to mess with the gates, a set of "maintained contact, normally open" pushbuttons in small boxes would work too (pull it out to start, push in to stop).

You'd need a 24VAC transformer (under $10), some mini-pushbutton switches from Radio Shack ($5), a contactor ($20) and box to put the contactor in ($10). You'd run doorbell wire or similar to your blast gates.

An alternate solution is the true remote controlled "Long Ranger" style on/off setup where you'd clip a remote to your belt.

If you're interested in more info about how to wire these, holler.

Rob

One of the 3-way switches is by the door, the other is close to the dust control unit and to the table saw / jointer / planer location. I agree that those locations are not ideal, but they were the best that I could think of.

I did not know about the possibility of switching the unit off when all blast gates are closed. That sounds ideal and, yes I would appreciate more details.

I don't like the type of remote that you carry around with you because I always seem to missplace them, but remotes in a semi-permanent places work for me.

[Rob Russell]

Hi Frank,

I received your email. I hadn't forgotten about you :-).

I'm on "vacation" for another week or so. The last few days have been spent staying with my godfather who has Alzheimers (sp?). Two+ days of parking him in his rent-a-bay warehouse unit working in Florida heat to throw away trunkload after trunkload of stuff. That and we're disrupting his "routine" - but he's glad to see us. We're at the stage now where he's going to have to give up his car and move from his apartment into a place where he can get some help, even though he's still competent and functional 95% of the time. He deson't know that yet and is not ready to accept it. Oyyyy (and I'm not even Jewish!).

I will post a schematic for the DC controls I described. I've got our laptop with us, but haven't had time to work on a diagram. Next week when we move to a calmer location, so earliest post will be the week of 4/19.

I basically don't have Internet access which is why you haven't heard from me in the forum.

Rob

[Frank Pellow]

Other than the remote control for my dust control (for which I am awaiting information from Rob), the plans are now complete (I hope) . I made a few very small changes since posting the schematic on the 3rd of April so I went back and replaced that attachment. I now have wiring diagrams and am attaching them here.

[Chris Padilla]

Frank,

Maybe I missed it in this long thread but why aren't most of the light switches near the door?

[Bob Hovde]

Thanks to everyone who contributed to this thread. Although my planned shop would fit into one corner of Frank's shop, I need to bring a new electrical service from the house to the garage (shop) - about 80 ft - and the tips I've learned here have helped me greatly in planning the electrical layout for my new PM 3520A and JET 18" BS ( :) stealth gloat!) that arrived yesterday in the rain. (Pictures to follow, but this will take some time.)

Bob

[Frank Pellow]

Chris, most of the light switches are near the door that I plan to use the most often, that is the single door.

[Chris Padilla]

Doh! Sorry, I am blind. Darn it...I swear I looked carefully as it just didn't make sense for you to do it that way! :D

[Bob_Hammond]

One more question. :)

Are you sure that you don't need a 30amp 230v ckt for your tablesaw? I wired my Unisaw with a 20amp, and about every couple of weeks I'll get a nuisance trip. I keep meaning to upgrade to 30amp, but I haven't gotten around to it yet.

Bob

[Frank Pellow]

One more question. :)

Are you sure that you don't need a 30amp 230v ckt for your tablesaw? I wired my Unisaw with a 20amp, and about every couple of weeks I'll get a nuisance trip. I keep meaning to upgrade to 30amp, but I haven't gotten around to it yet.

Bob

The table saw that I think right now that I would like to get is the General 350 and it is rated at 230 volts 12 amps. That should be plenty. However, I might end up getting a different saw, so it might be prudent of me to wire for 30 amps. Thanks for the tip.

[Frank Pellow]

The change that I made to the way that I am insulating the floor means that I no longer have space between the sub-floor and floor to run wiring or to install floor outlets. The floor outlets will now be ceiling outlets and the wires that were running through the floor will now run through the wall and ceiling. I have changed the diagrams that I previously included with posts #28 and #32 to reflect these changes.

[Jim Becker]

Frank, why don't you put some conduit in for those floor outlets--install it before you put the decking on. 'Shame to have to have everything hanging and with proper strain reliefs, it may actually be more expensive than the conduit! But even Romex stapled to your joists prior to installing the insulation should be workable, too...unless you have some very different rules to play by.

[Frank Pellow]

Frank, why don't you put some conduit in for those floor outlets--install it before you put the decking on. 'Shame to have to have everything hanging and with proper strain reliefs, it may actually be more expensive than the conduit! But even Romex stapled to your joists prior to installing the insulation should be workable, too...unless you have some very different rules to play by.

Jim thanks for the advise. It is good, but I don't think that I will follow it. In a way, it was a relief to me to jetison the floor outlet plans. I was having trouble finding acceptable (to me) floor outlets and even the couple I found that I did not like were very expensive. Also, I have been getting advise from others not to have floor outlets at all.

[Rob Russell]

You're going to have "stuff" hanging down from the ceiling anyway - like 5" pipe or hose for dust collection. I wouldn't see it as a big deal to attach a piece of 4"x4" to use as a mounting point for your pipe/hose and electrical. It also gives you a place to hang "stuff" near your saw. Yeah, you've gotta think of where you want it so the pole isn't in the way. The DC pipe/hose is going to be there anyway, so use that to determine where is best for you.

[Frank Pellow]

Yes Rob you are right that I am going to have "stuff" hanging down from the ceiling anyway. I was thinking along the same lines after my reply to Jim. That fact really clinches the "no floor recepticle" decision for me.

[Rob Russell]

Frank,

Question for you on the blast gates for the DC system. It should be sort of obvious that these home-made gates will interact with a switch that starts/stops the DC.

So, my questions ...

How important is it to you to have some sort of indicator light/led that tells you which blast gate(s) is(are) open? It isn't particularly difficult to do, but it does make a difference in the switches used when you build the blast gates. A minor point is specifying a source for 24 volt lights, but that's a small thing.
Do you have Ebay access? I ask because it's a great source to buy parts cheap for projects like this.


I guess I'm asking anyone who is following this thread, not just Frank.

Rob

[Chris Padilla]

Rob,

If I missed this already, sorry, but have you posted the "know-how" for the DC electrical system?

I've got the part for the remote controlled DC in hand but I like the idea of pulling open a blast gate for whatever machine I'm on and having the DC turn on then.

[Jim Becker]

I've got the part for the remote controlled DC in hand but I like the idea of pulling open a blast gate for whatever machine I'm on and having the DC turn on then.I have to be honest with you, I do prefer multiple points for switching the system off and on and that's what I have, but would not like it tied to the gate operation. Why? I move from machine to machine without turning the DC off. I also will sometimes leave it running for a few minutes between operations with the gates closed just for convenience and to cut down on the on-off cycles to the motor...especially as it's "almost silent" with the gates closed and with the accoustic dampening that the closet gives it. But this is just my particular preference...yours may be different.

That said, my switches (RF remotes) are located either next to the gate or on a particular tool where they are convenient to use. Some of the gates are not in a comfortable location to be used for on-off purposes, too, I might add, such as the one at the lathe and the miter saw.

[Rob Russell]

Chris,

No I haven't posted anything yet on how to wire this stuff up.

There are multiple ways to do this:

Use the blast gates to start/stop the DC. Any gate open means the DC is running, so the DC runs until all blast gates are closed.
Put Start/Stop stations by each blast gate. Hit a Start button and open a blast gate. The DC runs until you hit Stop, although the Stop could be any of the Stop buttons you have, not just the one in the station where you hit Start. The Start/Stop buttons are independent of the blast gates.
Want an indicator light on open blast gates? Is that tied in to the first or second method of controlling your DC - makes a (small) difference.
It's even possible to wire it so opening a blast gate starts the DC, but you need to hit one of the Stop buttons to kill it. Even closing the open blast gate wouldn't kill the DC. In that situation, I'd think you want an indicator light to tell you if a blast gate is open.


Just curious as to how fancy folks want to get.

Rob

[Rob Russell]

Some of the gates are not in a comfortable location to be used for on-off purposes, too, I might add, such as the one at the lathe and the miter saw.



Jim,

If you can reach the gate to open/close it, you can have the gate operate a switch. Is there something else I'm missing?

The remote switches are nice too - if you're not the sort who loses them or minds having something like that you need to carry around. The only other nice thing about the remotes - if you want to spend the $, is that you can velcro mount a remote by the on/off switch of every machine. That makes turning things on and off a "walk to any machine" sort of thing and the blast gates can be standard, off-the-shelf prefab units. It's harder to do "cool" indicator lights with pre-fab gates, though. ;)
Rob

Rob

[Jim Becker]

Rob, as an example, the gate for my lathe is up on the wall behind the headstock end and requires me to walk around the machine to pull it open--my arms are just not long enough. I have an RF remote mounted right on the headstock to turn the DC off and on. Since my BS is right next to it, I use that same remote for the BS. I don't carry any remote around...they would wander into the house. I have 7 in the shop and they are in fixed positions mounted with double stick tape! There is always a remote within a few steps of any workstation or mounted on the workstation itself. (At the TS, it's right on the overarm guard, for example)

[Rob Russell]

Jim,

I figured it was something like that. For the cost of that remotes, I'd have been tempted to go with Ecogates and really automate the setup.

Rob

[Jim Becker]

For the cost of that remotes, I'd have been tempted to go with Ecogates and really automate the setup.
'Got the remotes for $3.99 each...including batteries...when they were on a close-out sale at Smarthome.com. (Older version) :D

[Chris Padilla]

I don't think I've seen Ecogates available in 6". Are they now?

[Rob Russell]

I don't think I've seen Ecogates available in 6". Are they now?

Oh yeah - they have them up to something like 14" for industrial applications. 4", 5", 6" - then 8" is the next step.

[Chris Padilla]

Doh! I just googled Ecogate and found everything. Expensive system...would be interested to see The Rob Russell Cheap-o Ecogate solution. :)

[Frank Pellow]

Rob, I see that you, Chris, and Jim have been having quite a conversation today while I was not looking.

I like the second option that you have listed, that is:

Put Start/Stop stations by each blast gate. Hit a Start button and open a blast gate. The DC runs until you hit Stop, although the Stop could be any of the Stop buttons you have, not just the one in the station where you hit Start. The Start/Stop buttons are independent of the blast gates.

I do not plan to make my own blast gates.

I do have access to Ebay

[Frank Pellow]

Rob, I am going to ask you a question about my wiring that I can't seem to find an answer for elsewhere.

A little ofver a month ago, you responding to this tread with:

"Tony Laros’ comment about alternating receptacles on circuits is just another way of wiring a multiwire circuit. The only “cost” to run a multiwire circuit is the difference between 12/3 and 12/2 NM cable (“Romex”) . The benefit is you have a whole second circuit to pull power from. Whether you chose to splitwire receptacles or use Tony’s scheme of alternating receptacles between the 2 hot legs – this is a really cheap way to give yourself better power access around the shop."

As a result of the advise I received from you, Tony, and others, I am going to run 12/3 around the shop and every second duplex receptacle will be oin a different circuit. My question has to do with hooking enabling GFCI on these circuits. My guess is that I need to purchase 2 GFCI receptacle and make these the first 2 receptacles in the run (one on each circuit) then place the remaining receptacles on the load side of these two. Will this work? Is there some way I can get away with only one GFCI receptacle?

[Jim Becker]

You may need to use a 240v GFCI at the panel (built into the breaker) for this "alternating circuit" arrangement, but I could be wrong about that. If so, it would raise your cost considerably. 12-2 is pretty inexpensive stuff, so running separate lines for each circuit isn't out of the question, too, despite the appearance that 12-3 with alternating circuits might be "cheap and quick".

I'm looking forward to Rob's knowledge on this one!

[Frank Pellow]

The cost of GFCI breaker is very high and, as you point out Jim, and 12/2 wire is not that expensive. So, that may be my solution.

[Rob Russell]

Frank, Frank, Frank – why do you want to do the right thing and GFI protect your receptacles … ;)

Unfortunately, (as Jim B. guessed) a traditional multi-wire circuit can only be GFI-protected by a GFI breaker. You can use the cheaper route of (2) GFI receptacles if you run 12/4 or (2)12/2.

Here’s why and please pardon the length of the explanation, but it will help you to understand why this is true rather than just taking my word for it. Also, where I reference the NEC, I do know that the NEC doesn't apply in Canada, so you're sort of on your own to the verify what is and isn't code up there. Even in the U.S., the local AHJ (Authority Having Jurisdiction aka the "building inspector") can modify the code.

First – a definition. The proper term for the “neutral” is the “grounded” conductor, as in the “intentionally grounded” conductor. This conductor is a current-carrying conductor and, on a 120 volt circuit, carries just as much amperage as the black or red “hot” conductor. The neutral is just carrying the current back to the panel. The green or bare wire, commonly known as the equipment grounding conductor or EGC, is properly called the “grounding” conductor. In the U.S., there have been attempts to get that EGC renamed in the NEC to the “bonding” conductor. This renaming attempt is because of the confusion that can arise between the terms “grounded”(neutral) and “grounding”(equipment ground) conductor.

A “ground fault” occurs when current that is supposed to flow back through the grounded (neutral) conductor doesn’t – which means it’s flowing somewhere else (like through the EGC or through you). Accordingly, a GFI breaker or GFI receptacle has a sensor that compares the current flowing out through the hot conductor(s) to the current flowing back through the neutral conductor. If the two current loads are the same, then no current is leaking out and everything is hunky-dory. If there is an imbalance between current flowing out and back, the sensor trips. For example, if the current flowing back through the neutral is low because you’re being electrocuted, the GFI sensor detects that lower return current and trips. This situation is called a ground fault, in that there is an alternate path for the current to flow to ground.

Given the above description of what a ground fault is and how the sensor works, you should be able to understand why a normal multi-wire circuit can’t be GFI protected simply by using a pair of GFI receptacles to protect each leg. The problem is the shared neutral. You could wire up the circuit. You could then plug in one tool and run it. The current flowing out the hot leg that receptacle was on would match the current flowing back in on the neutral. As soon as you ran anything on the other hot leg, you would cause one or both of the 2 GFI’s to trip. Remember that the current carried on the shared neutral is the difference between the 2 hot currents. 10 amps in on the black leg + 7 amps in on the red leg = 3 amps back on the neutral. 3 amps doesn’t equal either 7 or 10 amps.

There are a couple of ways to resolve this.
Use a 2-pole GFCI breaker. These breakers tend to be expensive.
Use (2) GFI receptacles and run independent neutrals for the 2 hot legs of the circuit. You’d either run (2) 12/2 cables or, if it’s available in your area, the newer 12/4. 12/4 NM has an additional neutral conductor, white with a red tag or stripe.


In terms of breakers, the only time the NEC specifices that you must use a 2-pole breaker is if you have both hot legs sharing the same yoke. The yoke is the metal strap that a duplex receptacle is built on. If you wire the outlets so the receptacles are on 1 circuit and you just alternate circuits as you run down the wall, you can safely use single pole breakers. While the code allows it in the U.S., if you were installing quad outlets (a pair of duplex receptacles) with a separate circuit feeding each of the receptacles, I’d still use a 2-pole breaker. That guarantees that both circuits are dead when you open up a box to work on it. If you’re running all the wiring in the walls, this is less of an issue. Other than the last box on each circuit, you’ll only have an incoming supply and outgoing feed for a single circuit in any given box, so multiple circuits in one box isn’t a danger.

Sorry for the length of this.

Rob

[Jim Becker]

Rob, that was EXCELLENT. Even normal folks like me :D can understand your clear and succinct explaination.

[Frank Pellow]

That is a GREAT explanation Rob! You should write a book. So, although I do not like your answer, I am happy. :)

Actually, code in Ontario does not force me to use GFCI receptacles in my shop, but I have decided to do so anyway.

I will use the two 12/2 wire approach.

[Rob Russell]

Rob, that was EXCELLENT. Even normal folks like me :D can understand your clear and succinct explaination.

Thanks Jim. I figured if you could understand it, anyone could. :rolleyes: :rolleyes: :rolleyes:

[Rob Russell]

Doh! I just googled Ecogate and found everything. Expensive system...would be interested to see The Rob Russell Cheap-o Ecogate solution. :)

Chris,

I actually spent some time trying to engineer a neat, clean and CHEAP alternative to the Ecogate product. Given that my blast gates will include 1) 5" and 6" gates and 2) two gates at once for the saw shaper (1 for the internal under-the-table main dust port and 1 for the overarm blade guard dust hood), the cost of the Ecogate system for me is really in the $700-800+ range. I also need to factor in current sensors instead of vibration sensors and a contactor because of the 3-phase power. Other Felder owners have had problems with the mass of the machines dampening the vibrations enough so the standard vibration sensors didn't pickup the machine's startup. I'd suspect that the larger MiniMax stuff would have the same "problem" of being too smooth.

It's not that big a deal to get a DC to start automatically based on a machine starting up and a delay timer relay is an easy way to keep the DC running after you shut the machine off. The challenge comes in if you want the blast gate(s) to automatically open and close. I looked at pneumatically operated gates (driven via air cylinders) and it gets sorta complicated. That plus you've got to have air lines running all over the place.

I'm still noodling it around, but nothing yet. :confused:

Rob

[Rob Russell]

I will use the two 12/2 wire approach.

Good decision. Limiting the "power access" in your shop along that back wall is something that would likely have had you kicking yourself later.

[Chris Padilla]

Frank,

Are you doing 2 separate boxes or 1 box for the multiwire circuit? In other words, two separate boxes for a duplex outlet each or 1 box that hold 2 duplex outlets.

[Rob Russell]

Frank,

Are you doing 2 separate boxes or 1 box for the multiwire circuit? In other words, two separate boxes for a duplex outlet each or 1 box that hold 2 duplex outlets.

Chris,

My interpretation of what Frank is doing is (and I know I'm not Frank :)):
a series of single gang boxes.
each box will hold a single duplex receptacle.
each box/receptacle will be on a single circuit; i.e., the receptacles will not be "split-wired".
the boxes will alternate circuits along the wall.
there will be a total of (2) circuits feeding the receptacles.
the first receptacle in each circuit will be a GFCI receptacle with 20-amp feed-thru rating (vs. 15-amp feed-thru rating).
the duplex receptacles could be either 15 or 20-amp rated, Frank's choice.
the circuits will be protected by individual, full-size, 20-amp breakers, mounted side-by-side to guarantee that both legs of the panel are used.

Frank - how'd I do?

Rob

[Chris Padilla]

Well, sure, Rob...NOW he is going to do it exactly that way! :p

[Frank Pellow]

WOW Rob you are absolutly correct!

Not only are you a good teacher but you listen to what your students say.

[Frank Pellow]

I have updated the electrical diagrams that are attached to posts #28 and #32 in this thread. The electrical changes are minor but the quality of the diagrams is a lot better.

[Jerry Olexa]

Just get a long electrical cord and run it down from the house! Only joking!
Sounds like you're getting good advice!! Jerry:)

[Frank Pellow]

Just get a long electrical cord and run it down from the house! Only joking!
Sounds like you're getting good advice!! Jerry:)

You might be right Jerry :rolleyes: -it's what I am doing right now and that seems to work OK.

[Rob Russell]

This is a test upload of the schematic for a Dust Collection control system using a series of Start-Stop stations mounted around the workshop. Based on how clear this looks, I can move on to the next step.

[Jim Becker]

Rob, on the 120v side of the control transformer, wouldn't the return path be the neutral? (Yea, I know they meet up down the line, but...) 'Just cuious why you drew it that way.

[Rob Russell]

Jim

Note the difference between the GRD (Grounded conductor, aka the Neutral) vs the EQP GRD (Equipment Ground) hanging off of the motor.

One of the next steps is some prose to explain the schmatic.

Rob

[Jim Becker]

Note the difference between the GRD (Grounded conductor, aka the Neutral) vs the EQP GRD (Equipment Ground) hanging off of the motor.
Ok...I see what you mean.

[Chris Padilla]

Rob,

What are the values and purpose of the 3 caps? I know...the prose is coming, right? :D

[Rob Russell]

Chris,

There aren't any capacitors in the schematic. Are you looking at the contactor coil (has M-24 in it) and thinking that's a cap? The other things that look close to a cap symbol in some legends is the 2-pole circuit breaker.

Rob

[Chris Padilla]

Rob,

Right below the 2-pole CB and above the M-24 looks like two caps. The third one is in line to the left of the two. They weren't labeled so I was confused what they might be...look like caps to my EE eyes but I couldn't fathom their purpose!

[Jim Becker]

Chris, could they merely be the connectors for the contactor? (Say that ten times fast...:D)

[Rob Russell]

Chris,

Those are the NO contacts in the contactor. The ANSI and International symbol sets I found showed that as a NO, run a slash across the parallel lines to make it a NC contact. You can see such a NC contact as the Overload Contacts.

Rob

[Chris Padilla]

"I see!" said the blind king. :) In my world, those are caps! :D I think a dashed line around the contactor to indicate it as a kind of "black box" would be appropriate to avoid confusion. A cap with a slash through it would be a variable cap! :D I'm so confused!!!!! ;)

[Rob Russell]

Actually Chris, I'd thought about encapsulating the devices in dotted lines to demark the individual devices, even though that isn't really the "right" way to do a schematic. That's one of those "it makes the wiring clearer for us layman types" where a EE would be used to the schematics without the encapsulation of the devices.

That's probably one of those things I'll add to the next version. Fortunately, this is in Excel so it's easy to add the dotted line boxes.

[Frank Pellow]

Thanks Rob, I think that I will be able follow your diagram. The proof will come about next October or November when I actuall attempt to do so. And, I think that it will help me if you do follow your thought: "I'd thought about encapsulating the devices in dotted lines to demark the individual devices" with action.

[Frank Pellow]

I hope to get started next week. I will be getting (paid for) assistance from an acquaintance who is an electrician. I had wanted to do everything myself but this will be faster, maybe better, and I am getting really good process on components through him. Those who had been looking at the main thread (http://www.sawmillcreek.org/showthread.php?t=7769) about my shop construction and at the dust collection thread (http://www.sawmillcreek.org/showthread.php?t=7853), will have seen that I simulated the placement of everything in my shop as a final "working test" before commencing with the electrical installation.

I think that things have really worked out well and thank everyone here at Saw Mill Creek who helped me.

There are a couple of attachments:

(1) The final electrical layout

(2) A shot of my shop taken earlier this morning showing some of the simulation of electricity and ductwork

[John Miliunas]

Frank, the more I look at it, the more I like your idea of doing a mock-up of where/how everything will be! :) I "walked" into my shop already made by the previous owner and sure do wish I'd have had the chance to do something like you're doing. Don't get me wrong....I'm happy with my shop and the much greater size than what I had previously, but little stuff like outlet and light placement leaves a bit to be desired. You're doing well over there, Frank! :) Keep it up and please, continue sharing your ideas and progress pics! :cool:

[Jim Becker]

John, I think that Frank has set the new standard for shop planning/construction techniques. This is by-far the best idea I've ever seen for working the kinks out of "shop utilities" before committing to them!!

[John Miliunas]

John, I think that Frank has set the new standard for shop planning/construction techniques. This is by-far the best idea I've ever seen for working the kinks out of "shop utilities" before committing to them!!

Jim, couldn't agree more! As mentioned, my shop was already in-place, so all I could really do was to play with machine placement on paper before committing to it. That worked out quite well, actually, but I wish I would've done what Frank did with my DC runs! :o I think anyone going from the ground up could and SHOULD incorporate this process to their own building process! :cool:

[Frank Pellow]

John, I think that Frank has set the new standard for shop planning/construction techniques. This is by-far the best idea I've ever seen for working the kinks out of "shop utilities" before committing to them!!


Jim, couldn't agree more! ... I think anyone going from the ground up could and SHOULD incorporate this process to their own building process! :cool:

Thanks for the kind words -a guy could get a swelled head.

Maybe I should open a sideline business making a selling Frank's Funcky Fake Flourescent Fxtures. :D

[Steve Stube]

Very nice planning Frank. I do not see the DC wiring, am I missing something?



FWIW, I want to add my 2 cents regarding the schematic in post #72. I think the control of the DC can be accomplished in another way that is both simpler and cheaper than the ckt. shown. I concur that what Rob outlines will work and you may still choose to follow his plan (which is excellent) but I'm compelled to mention an alternative route. If Rob agrees that it has merit perhaps he will add his flair and diagram it for you.



In brief (I hope);

Enter the shop and flip a switch to energize the 24V 2 A transformer ckt. {If the DC unit is remote so that it can not be seen or its operation heard an additional panel lite at this location, to indicate it is running, is desirable (low voltage, wired in series with the DC motor control coil). Big shops.} On the output side of the transformer that feeds the motor contactor you install a bi-stable relay (sometimes called latching relay, impulse relay, flip-flop relay and maybe by some other terms which may or may not be correct - but it is one of these; http://relays.tycoelectronics.com/datasheets/S8990_DS.pdf

A Tyco relay is shown, but other companies do/did make this same type relay. I have at least one non Tyco in a system I use for remote lighting with multiple switching points. Most garage door openers use one. The coil of the bi-stable relay is powered by the 24V transformer as is the motor contactor that is under the control of this bi-stable relay.



As you can see in the pdf different coil voltages are available (we will concern ourselves with the 24V option for the discussion here). Now you can put any number of push button switches in series*** with the output of this bi-stable relay. It is like wiring your door bell ckt., all low voltage with simple (cheap) make - break switches (door bell buttons if you like). Each time a button is pressed and released the motor ckt. is either latched on or off until any one of the buttons is depressed to give the opposite state. Clear as mud?



I use 4 conductor phone wire to wire the push buttons (I double up on the wire by twisting red and green together and black and yellow together although it may not be necessary with only a 375 mA coil). The output side of the bi-stable relay needs to be wired to handle the load of the motor starting relay coil.


*** added for clarity; maybe this point could be clearer if I said that the switches (doorbell buttons) are wired in parallel but the sum total of these are in series with the 24V DC motor relay coil.

A wiring diagram may help.
http://img.photobucket.com/albums/v19/ceethese/Posted%20photos/DCRemoteSwitching.jpg

[jeff Reynold]

I agree with Bob you need some outlets in the middle of your shop either in the floor or on the ceiling. I bought some retractable cords that work good from the ceiling.

[Rob Russell]

Well, it's taken a while (apologies for the delays), but here are 3 schematics for varying Dust Collection start/stop control schemes. There are others, it becomes a matter of how you want to let your imagination run wild.

The simplest is the wall switch one. There are probably rules about running low voltage wiring and not surface-mounting it, but I frankly haven't read up on those.

I also wanted to include some explanatory prose for the various diagrams (there are 4 separate images, they just look all run together).

The Contactor and Overload used in each diagram is also known as a motor starter. The point of this setup is that the contactor is just a switching mechanism and provides no protection to the motor for current overloads. The overload is like an inline fuse which is very specifically sized to the current draw of your motor. The section of the NEC that applies to motors and motor control (Article 430) separates short circuit protection (provided by the circuit breaker) and overload protection (provided by the overload) into 2 separate areas. That’s why I’m showing both on the schematic. If someone can post HP and FLA ratings from a couple of the DC motor name plats, I’ll post the recommended overload sizes.

You may wonder why there are (2) 12v indicator lights on the 24 VAC schematics. I wanted an indictor light to show Frank that the “system” was powered up. That’s why there are 2 switches for power to the transformer – 1 by the DC unit and 1 by the door. Walk in the door and power up the system (turn the transformer on). Anyway, 24 VAC indicator lights are available but they tend to be expensive, as that’s typically something you’d use in an industrial control setting. Knowing that Frank has a thrifty side, it seemed appropriate to use an alternate solution. Accordingly, (2) 12v lights in series yields an effective voltage of 24v and 2 lights will be brighter than 1.

For the schematic that used normal light switches, one conductor in the switch loop is always hot, it’s just that the connection all the way back to the DC isn’t made. I considered adding a master On/Off switch by the DC – but the point of that layout was to keep it as simple as possible. Want to work on the switches on the system? Turn off the circuit breaker. Want to work on the switches for the 24 VAC system? Make sure the transformer is off (although it is safer to kill the circuit breaker). Also, note that the white conductor shows as being “marked” with black tape to indicate that it’s hot.

All the pushbuttons used in the schematics are “momentary contact”.

Note that there is a difference between the “GRD” and “EQP GRD” symbols. The “GRD” symbols are what is commonly called the Neutral.

It’s a rather important to note that the Start/Stop pushbutton style of system needs a 3rd contact on the contactor. This extra contact is for the “holding” circuit. Basically, you start the system by pushing in one of the Start buttons. When the contactor closes, that extra contact also closes and sends power out through the series of Stop buttons and back to the contactor’s coil. Notice that the Stop buttons are wired in series, so interrupting the holding circuit anywhere kills power to the coil and the contactor opens.

If any of this doesn’t make sense or there are things I missed (quite likely), just holler.

Rob

[Frank Pellow]

I agree with Bob you need some outlets in the middle of your shop either in the floor or on the ceiling. I bought some retractable cords that work good from the ceiling.

Jeff. there are 6 ceiling receptacles shown in the diagram (3 at 240 volts and 3 at 120 volts). Did you not see these or do you think that I need more than six.

I would appreciate knowing more about the retractable cords that you mentioned.

[Frank Pellow]

Very nice planning Frank. I do not see the DC wiring, am I missing something?

...


Thanks for the compiment on the planning Steve.

Re the DC wiring. I am not yet sure whether I will do the wiring as proposed by Rob. My fallback is to simply wire two 3-way and one 4-way switches near to the dust port. These are shown as the switches with #8 on them in the diagram.

[Steve Stube]

Frank, I did see #8 (after posting).

I have included a (not-so-fancy) wiring diagram for the DC remote switching model I described in post #89 of this thread.

[Rob Russell]

Steve,

The main reason I haven't used a "flip-flop" relay as you propose is that the DC can be latched in an "On" position so that, when you walk into the shop and power up the 120/24v transformer, the DC powers up when you don't expect it.

That can't happen with straight contactors/motor starters.

My low cost suggestion (std 3/4-way switches is in diagram #3).

Rob

[Steve Stube]

The main reason I haven't used a "flip-flop" relay as you propose is that the DC can be latched in an "On" position so that, when you walk into the shop and power up the 120/24v transformer, the DC powers up when you don't expect it.


Well the quick response (solution) to that concern Rob is to hardwire the 24V transformer (no switch at the door) for 24/7 operation just as you have in a door bell or furnace system. Now, assuming you turned it off when last used, pressing any button will turn it on. I should have left out the switch at the door part (not shown in the wiring diagram) in the description. i.e., "Enter the shop and flip a switch to energize the 24V 2 A transformer ckt." I was describing it from memory and was confused with a security system DISARM SWITCH I use elsewhere. Thanks for catching that. Steve

[Rob Russell]

Steve,

Thinking about it a it more, energizing/deneergizing the control circuit transformer won't do anything to affect the mode of the DC because the relay is mechanically held. What would be a problem is if Frank installed a master kill switch by the DC and turned the system off that way rather than by hitting a pushbutton. In that case the control circuit could still be closed and the DC would power up next time he turned the whole system on.

It would still make sense to have a kill switch for the transformer so you don't waste power energizing the control circuit when you're not in the shop.

Rob

[Rob Russell]

I am not yet sure whether I will do the wiring as proposed by Rob. My fallback is to simply wire two 3-way and one 4-way switches near to the dust port. These are shown as the switches with #8 on them in the diagram.

Frank,

If you do want to be able to replace the regular wall switches with start/stop pushbutton stations, you will need a total of 4 conductors. I'd suggest running (1) 14-3 and (1) 14-2. Technically, that doesn't met the NEC because it means the circuit conductors are being split between cables, but I really don't think that's a huge deal. You could ask your AHJ about that. You could run plastic conduit and pull individual conductors. You could find 14/4 (available now). You'll need an oversize box (likely a 4" square) if you want to be able to change to the pushbuttons.

There is a possibiity that you could use a single 14/3 cable and by using a contactor with (2) aux contacts (1 Normally Open for the Holding Circuit and 1 to feed the Start circuit, but sharing 1 conductor out on your switch loop). I'd want to test that to see if the contactor would catch and hold or just chatter.

Personally, while the pushbutton stuff is cool and neat, there is something to be said for the simplicity of normal 3/4-way switches. Anyone who does wiring should understand those. The same isn't necessarily true of the Start/Stop circuit, even though it is a very old wiring technique.

Rob

[Frank Pellow]

Thanks Rob. I will study your diagrams and information some more then will decide soon which approach to take.

[Steve Stube]

Rob,


It would still make sense to have a kill switch for the transformer so you don't waste power energizing the control circuit when you're not in the shop.

Please note that there is NO load on the 24V transformer (incomplete ckt. for either coil) unless the DC system is running.

[Rob Russell]

I guess that I'm missing the point on the 24 VAC transformer. If the transformer is energized, regardless of what the DC is doing, it's drawing a very smll amount of current and generating a very small amount of heat - right? If I'm wrong, that's fine. I don't claim to know everything about electricity and am glad to learn new aspects about electron-related stuff.

[Steve Stube]

I was responding to your comment;


It would still make sense to have a kill switch for the transformer so you don't waste power energizing the control circuit when you're not in the shop.


There is no power wasted on an energized control ckt. - it's not energized when the DC system is off.

It seems you have jumped to a new topic, the inhearent losses of a transformer. Yes you are right, if it HEATS up, LIGHTS up or SPEAKS up then it MOUNTS up over time. If it does that open circuited to any degree the transformer is generally replaced.

The scheme I set forth was offered in hopes it could be useful to others. I like it and use it in a few different ways around my home and shop. It won't be accepted by everyone and maybe no one at all, that's okay with me. On the other hand, I refuse to pull the plug or remove the batteries from clocks when I leave the house to go to my shop only to have to power-up and reset them when I return thus saving all that $.

[Rob Russell]

If you do want to be able to replace the regular wall switches with start/stop pushbutton stations, you will need a total of 4 conductors. I'd suggest running (1) 14-3 and (1) 14-2. Technically, that doesn't met the NEC because it means the circuit conductors are being split between cables, but I really don't think that's a huge deal. You could ask your AHJ about that. You could run plastic conduit and pull individual conductors. You could find 14/4 (available now). You'll need an oversize box (likely a 4" square) if you want to be able to change to the pushbuttons.


Code update: starting with the 99 NEC, there is an exception that allows the conductors of a circuit wired with NM to be split between different cables. That means you could run a 14/3 and 14/2 and use the conductors for all the same switching system and you'd be fine. You could even run (2) 14/2 and use one of the conductors in the 2nd cable as part of a normal 3/4-way switching arrangement and you'd be fine.

Steve,

My point about the transformer, if Frank went with a low-voltage system (not needed - could use line voltage through pushbutton and drop the transformer, but ...), is that if the transformer is on, it's using current. That transformer humming away is using current regardless of the switches on the control circuit powered by the transformer. Whether the DC is running or not has no effect on the control transformer. I thought that was what I'd said earlier,although maybe not in those words.

Rob

[Chris Padilla]

What are all the colors in the 14/4, Rob? Bare copper, White, Black, Red, and.....? :)

[Rob Russell]

What are all the colors in the 14/4, Rob? Bare copper, White, Black, Red, and.....? :)

White w/red marker to identify the second neutral. If you were running a set of kitchen receptacles or a splitwiring receptacles where each half needed to be GFI protected, it would mean 1 less grounding conductor.

Based on the code, you could just run (2) 14-2 (or 12-2 if you're talking kitchen, because those would be 20-amp circuits).

[Steve Stube]

Rob, Yes, there no doubt will be some transformer losses, it's not a perfect world. If I were to guess at what those losses might cost over a period of say a year - my guess would be, less than $0.20. Do you have any better data? Transformer efficiencies? Fully loaded with the TYCO bi-stable coil I already mentioned running at 375 milliamps and 24 V it would use a little over $5.00 in a year BUT it only has that load on it while a button is depressed. That might be 5 minutes total in a year out of the 525,600 minutes available.

I have backed out the remote switching portion of the earlier diagram so that you may use whatever voltage you wish for the DC motor relay coil. Do keep in mind that the TYCO unit has (IIRC) 10 amps max contact rating. It now looks like this;
http://img.photobucket.com/albums/v19/ceethese/Posted%20photos/DCremotesw.jpg

I also include a photo of a couple of cube transformers (top & bottom views) which might help give an idea of size (note the standard 3 prong plug pattern to gage size) and a bi-stable relay. This particular relay has a 12 V coil and doesn't need as big a transformer as the TYCO units.
http://img.photobucket.com/albums/v19/ceethese/Posted%20photos/RelayXformer2.jpg

The transformer on the left is a 7.5 VA and the other is a 10 VA.

It only takes milliamps to operate the bi-stable relay. They are about 2" cube and plug in to 120 V outlet and can then switch ~10 Amps, more than enough to power your DC motor relay coil either at 110 V or 24 V whatever the case may be. The remote switching is pretty Mickey Mouse as circuits go. All the remotes are low voltage, door bell buttons (59 cents each, convenient to place one at each gate), phone or door bell wire (cheap cheap cheap, small, flexible), NO NEC involvement on the low voltage side, no conduit runs. Some button switches lend themselves nicely to taping connections and stuffing into a short piece of PVC tubing which then can be glued to the DC PVC near a gate valve eliminating the need for electrical boxes. The cube transformer and bi-stable relay might be located in the DC motor control relay box and wire attached to the runs (for example) using tape or glued on PVC ferrules. Use your imagination.

End of pitch.