Shop wiring question...

[John Cavanaugh]

Well Im finally getting around to fixing the biggest problem in my garage shop, namely not enough power.

But I do have a few questions.

Is there any way to ground fault protect 240v receptacles without resorting to using gfci breakers??

Has anyone ever used "refurbished" breakers?? A new 240v, dual pole, gfci breaker is anywhere between 150-250, but I have found some refurbished ones for like 90.

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John Cavanaugh

[Don Baer]

John,
In answer to you first question the answer is no.

I question are GFCI's required on 220 V circuits in your area. After all your dryers circuirs are 220 V, they are in an area where water is around and they're are not on GFI's.

To answer your second question yes. I have uesed the refurbished ones and had no problems..


Hope this helps.

[John Cavanaugh]

Don,

Im not aware of any code requirements for gfci for 240v in my area, though I think there might be something about gfci for 240v appliances in garages/basements in the NEC 2005, but then again Im not an electrician.

I think the main difference with dryers/etc is that they are "stationary" equipment, whereas in my shop Ill have different things plugging into the 240v outlets. Regardless, I figured since I was doing this project I should probably do it "right" or at least as close as practical.

For what its worth, Im definitely in the group that believes that 240v is the way to go for power tools if you can do it. I plan on converting my tablesaw, bandsaw & jointer after the electrical project is complete.

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John Cavanaugh

[Barry O'Mahony]

Im not aware of any code requirements for gfci for 240v in my area, though I think there might be something about gfci for 240v appliances in garages/basements in the NEC 2005, but then again Im not an electrician. Not in my copy of the 2005 NEC. ;) 'just for 15A & 20A, 120V receptacles.

The reason for this is that the floor is usually conductive (concrete), and these receptacles sometimes have frayed and/or poor condition extension cords or equipment plugged into them. Kinda dangerous, no?

Just make sure that properly grounded outlets get installed. Grounding the equipment properly will keep you safe. BTW, that means NOT using the old style 3-wire dryer outlets (2 hots plus neutral) for your tools. These outlets are now illegal for new installations, anyway.

[Dev Emch]

Hubble twist lock style plugs are the rage and they work very well. I love them.

But you can get hubble plugs that install into conventional receptacle boxes for say 240 volt single phase. The plate cover has a single hole about 2 inches or so in the middle. Looks good, workes great and its a twist lock. But better yet, its an acceptable alternative to using those goffy dryer outlets and other kludge connectors for these type of tools. I have yet to find an inspector who did not like the use of hubble twist locks!

[John Cavanaugh]

Regarding the plugs.

I had planned on using Nema 6-20R, but it sounds like folks are recommending something more like the Nema L6.

Should I use those plugs instead?? Any particular reason other than the "locking" aspect??

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John C

[Norman Hitt]

Regarding the plugs.

I had planned on using Nema 6-20R, but it sounds like folks are recommending something more like the Nema L6.

Should I use those plugs instead?? Any particular reason other than the "locking" aspect??

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John C

John, they are a heck of a lot easier to plug and unplug than the older type 220 plugs. I absolutely hate to unplug our dryer because it is so hard to get out, and it's hard to get a good grip on also. I'm always afraid I'm going to forget and let my fingers get down on the prongs while pulling it out, and that would be a "Shocking Development", no? Any recepticle that you will probably be plugging and unplugging a lot would sure be better if it were a twist lock.

[Kirk (KC) Constable]

Shop carefully...you might see a LARGE difference in price between the biggest box store and other places. In other words, my experience has been that HomeDepot is awfully proud of their electrical parts...and 230V plugs and receptacles in particular.

I won't put a twist lock on the tablesaw next time. I plug/unplug it frequently enough that it's become a pain to take that extra 2 seconds to make sure the prongs are lined up correctly...and more importantly, if I ever need to yank that thing out of the wall RIGHT NOW for whatever reason, I want it to come out RIGHT NOW.

KC

[Barry O'Mahony]

Regarding the plugs.

I had planned on using Nema 6-20R, but it sounds like folks are recommending something more like the Nema L6.

Should I use those plugs instead?? Any particular reason other than the "locking" aspect??

--
John CEither one; I find the L6's easier to plug and unplug: a quick twist and they pull straight out easily (or insert easily). Just don't use the NEMA 10-'s.

[Bill Lewis]

Not in my copy of the 2005 NEC. ;) 'just for 15A & 20A, 120V receptacles.And yet you can have a 15A or 20A 120V receptacles that are not GFCI (in a garage) if it is a dedicated circuit, like for a freezer, or a door opener.

Just make sure that properly grounded outlets get installed. Grounding the equipment properly will keep you safe. BTW, that means NOT using the old style 3-wire dryer outlets (2 hots plus neutral) for your tools. These outlets are now illegal for new installations, anyway.You can have a 240V outlet that has 2 hots and a ground, there is no need to carry a neutral.

[Rob Russell]

And yet you can have a 15A or 20A 120V receptacles that are not GFCI (in a garage) if it is a dedicated circuit, like for a freezer, or a door opener.


This is correct, but to meet the electrical code you have to be careful about the receptacle you install. If you're putting a refrigerator or freezer in your garage or basement and want to have a non-GFCI dedicated circuit for it, you must use a single outlet receptacle. That way, at least in terms of the building wiring, you can only plug 1 load into the circuit. The same is true for a washing machine circuit. In our laundry room, we have the washing machine right next to a laundry sink. The outlet for the washing machine is on a dedicated circuit, is not GFCI-protected but is a single receptacle - not the 2-receptacle outlet most of us are used to seeing.


You can have a 240V outlet that has 2 hots and a ground, there is no need to carry a neutral.

Well, that may or may not be true. A 240v only needs 2 hot legs to run, the grounding conductor is for safety. If you have a machine with a 120v work light, or a small 120v power feeder, or you want to build a router table into the extension table of your 240v tablesaw - a neutral becomes useful or required. If you are wiring the shop for 240v and put use the L14-20 series of plugs and receptacles, that would give you 2 hots, a neutral and grounding conductor at each location. If you have a machine that just needs the hots and grounding conductor, it's fine to leave the neutral terminal on the plug unused.

Ebay is a good source for devices like this - you can definitely save some $$$ if you're patient.

Rob

[Barry O'Mahony]

You can have a 240V outlet that has 2 hots and a ground, there is no need to carry a neutral.Yes, the L6 receptacles have this, and are the correct ones to use for power tools.

I was cautioning about the use of 3-wire 120V/240V ungrounded receptacles, which used to be used for dryers but are now prohibited for new installations. Some guys erroneously use these for power tools, because the outlet exists in the basement, and hook the neutral connection to the frame ground of the tool. This can be a shock hazard in some circumstances; i.e., if the branch is fed by a subpanel, because the neutral may not be at ground potential in that case (which is why this is no longer allowed for new dryer circuits).

[John Cavanaugh]

I won't put a twist lock on the tablesaw next time. I plug/unplug it frequently enough that it's become a pain to take that extra 2 seconds to make sure the prongs are lined up correctly...and more importantly, if I ever need to yank that thing out of the wall RIGHT NOW for whatever reason, I want it to come out RIGHT NOW.

KC

Kirk,

That is a very interesting point. I was really torn on which to use, but I think your comment on having an easier way to literally "pull the plug" if something goes wrong is a good idea. Im gonna stick with the NEMA-6 rather than the NEMA-L6.

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John C

[John Cavanaugh]

One other item I was planning for the electrical in my shop is a collection of switches (mounted above the door to the garage) that control the power to my 240 & 120 "tool" outlets.

My theory here is to use it as a preventative safety measure where I switch off all the power to the tools when I am done in the shop and go back in the house. I dont want my daughter (or anyone else really) wandering around the garage and turn on various power tools.

I thought about locking switches, but instead I thought I would place them out of reach (ie above the door frame) where its easy for me to get to but no one else.

Any thoughts pro/con on this approach?? Are there any code issues with having switches that high up on a wall??

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John C

[Don Baer]

I assume that the switches would control some sort of contactors. If this is the case I'd use 2 push button for each circuit. One to turn it on (Normaly open) and the other to turn power off (Normaly closed). In this way if for any reason why power is lost and a tools is turned on there is no way the tools couls restart until you push the on button. To many tools today use manual starters.

[Randy Meijer]

.....I thought about locking switches, but instead I thought I would place them out of reach (ie above the door frame) where its easy for me to get to but no one else.

That's what the guy thought who put his gun on the top shelf of his closet and we all know what happened, Kids are natural born climbers and explorers. I think those switches would be a temptation and a challenge for kids. Think I would feel a lot better about locking switches on the tools or put the "safety" switches at normal level and enclose them in a lockable box. If the sub panel is located in a convenient place, you could just put a lock on it if that is allowed by code and just flick off the appropriate breakers when you are done for the evening??

[Barry O'Mahony]

I my shop, the branch circuits for lighting, the refrigerator, and the one receptacle I use for battery chargers and the radio are powered all the time. Everything else is off a small subpanel. Power to this subpanel is through a 60A General-Purpose switch that is padlocked in the Off position when I'm not around. No matter how tempting the power tools may be to little ones, there'll be no mishaps on my watch.

One of the circuits off the subpanel powers a light red bulb that is lit whenever the subpanel has power. 'serves as a reminder to lock things up when I leave.