110 or 220

[John Bailey]

All the machines I'm looking at for my new shop are either 220 or 110/220. The DC and planer will definitely be 220, but the others can be either. It seems as though the 110/220 machines are easily switched. My question is, should I have most of my outlets be 220 (this is a new shop yet to be wired)? What are the advantages and disadvantages of 110 or 220.

Thanks, John

[Joe Mioux]

John:

Every electrician that I have dealt with always says when you have choice wire the motor for 220.

They say 220 v is easier on the motor.

So with that in mind and if it were my shop I would have atleast 4 or 5, 220 outlets, DC, TS, Planer, BS, and one extra.

Joe

[Roy Wall]

220 draws about half the amps compared to a 110 v motor.

110 machines are generally "lighter" duty and cheaper; plus "plug n play"......so easy to get rolling without electrical work. That is the beauty of 110v.

However, once the 220 is in.....it is just as easy.

I just added a 50 amp sub panel to my garage with 3 220 lines - I'm happy!!

[John Miliunas]

Yup, another vote for 220! The initial expense won't be that much more and you immediately give yourself a wider choice of future tools. Go for it!:) :cool:

[Jim Becker]

220 draws about half the amps compared to a 110 v motor.

The 120v/240v switchable motor draws the same agregate amperage (current) as the 120v motor...it's just split between two power legs and sets of windings. In all but a very few cases of "special" motors, the horsepower is the same, however, with either voltage setting.

Personally, I prefer to run stationary tools on 240v when I can--it was a real choice for many things I used to use, such as the Jet jointer and Jet bandsaw, but most of my prime machines now only accept 240v anyway. When you go above the 1.5hp motors, that's what it required if want to have reasonable wiring.

[Richard Wolf]

I have always dwelled on this myself and have never really got a satisfactory answer. We have alot of electrial experts on this site and may prove me wrong but here goes what I know. For machines in the size that you are talking about, 110 or 220, ;
1) 220 is not cheaper to run.
2) 220 is not more powerful.
3) 220 does not draw less amps.
4) 110 may run a little bit hotter if you run your machine continuesly.
5) 110 may dim lights in your house if the panel is small to begin with.
Nobody has ever told me of a real advantage to run a given machine at 220 instead of 110.
I could be wrong, I'm sure someone will point that out.

Richard

[Roy Wall]

Guys,

Why does a motor say.........for example.........

18 amps @ 110v or 11 amps @ 220............???

This makes sense that there's less resistance with 220...hence; less amp draw...

Richard - I agree 220 costs more to run!

[Jim Becker]

Richard - I agree 220 costs more to run!

Only in that the initial wiring might cost you more because the breaker, plug and recepticals cost a little more. A switchable motor that draws 15 amps at 120v and a draws 7.5 amps at 240v consume the same amount of electricity. (15 x 120 = 7.5 x 240) In your example, that 240v setting for that particular motor draws more than half of the 120v amperage...likely because it's been specially wired to take more advantage of the 240v setting in the realm of produced power. Delta used a motor like that on one of their contractors' style saws...1.5hp on 120v and 2hp on 240v...all because of the way the windings were configured. Not all switchable motors are that way...many are "even Steven" when you switch.

[Randy Meijer]

As I understand it your 220 motors will run cooler because of the lower amperage in the windings. A very basic rule of electrical equipment is less heat, longer life. All other things being equal, your 220 motors should last much longer than 110 motors!!

[Bill Neely]

I'd love to draw a picture here but I'm not up to it. There is no more current running through a motor connected 120V than one connected 240V. The windings are connected parallel for the low voltage - meaning each winding carries, for discussion purposes, 10 amps, they are connected together at the ends so only the wire bringing the power in actually sees more current. The 240V motor has the windings connected end to end (series) and each winding still carries 10 amps. Same amount of power consumed, same amount of heat.

Think of a 240V 200 watt light bulb - then a pair of 120V 100W light bulbs. Same amount of total power consumed.

[Rick Christopherson]

These are random thoughts not directed at any particular posting here. I can easily say this because the same misinformation is invariably repeated every time this topic comes up. (I will address the original poster's questions at the end of this.)

When I wrote Electricity in the Woodshop (http://waterfront-woods.home.att.net) some 8 years ago, my motivation was exclusively to address this issue of rewiring 120/240 volt motors. I just ended up taking the article further than originally planned.
=================
It is unequivocally false that a motor will run cooler at 240 volts. The internal windings of the motor are still receiving 120 volts regardless how the external wires are configured. The current through each winding is exactly the same at either voltage.
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I spoke with Delta at the AWFS trade show in Las Vegas last month, specifically about their mythical motor that had a higher rated horsepower at 240 volts. They acknowledged that there was a mistake in the nameplate rating, which has since been corrected. You won't find this mis-rating on any of their new saws.
=================
This is a specific statement: Roy, I have yet to see a motor with that type of rating, with the exception of the mistakenly rated Delta motor.
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There is absolutely no difference in cost between running 120 volts versus 240 volts. Your electric company does not give anything away for free. The meter outside the house reads the total watts, which is independent of voltage.
=================
The motor does not know whether it is on 120 or 240 volts. The windings inside see the same voltage either way. In the 120 volt configuration, they are in parallel. In the 240 volt configuration, they are in series. It is not easier on the motor. http://waterfront-woods.home.att.net/Articles/Electricity/splitwinding.gif
=================
The ONLY reason for changing a motor over to 240 volts is if the wiring in the shop is below code and cannot handle the current at the lower voltage.

When wiring a new shop, you should always be using 20 amp circuits for all outlets. There is not a single 120/240 volt motor on the market that will starve for power on a 20 amp, 120 volt circuit. 12 gauge wire requires a 20 amp circuit breaker, but the wire itself is rated for 25 amps. There is a built-in margin.
=================
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As for the original poster's questions: If the tool is portable or semi-portable, then you should stick to 120 volts for versatility. If you move the tool, you can always find a 120 volt outlet, but 240 volt outlets are not always where you need them.

If the tool is non-portable and you know that you will never rearrange your shop (or move to a new location) then you could go either way. If you go with 240 volt tools, don't make the common mistake of oversizing the circuit, as this completely defeats the whole concept. There is not a single 120/240 volt tool that requires a 20 amp or larger circuit at 240 volts!

It drives me nuts to hear people saying they are going to rewire their motors, and then install them on 30 amp circuits. If you are going to go through the hassle of pulling #10 wire, you may as well stick to 120 volts, because it is overkill as it is. (#10 wire really sucks to work with.)

The only time you need #10 (30 amp) wire on a 240 volt circuit is for a "true" 5-hp motor.

A 3-horsepower Unisaw/PM66 will operate on a 20 amp circuit.

ALL (no exceptions) 120/240 volt tools will operate on a 15 amp (14 gauge) circuit at 240 volts with power to spare. As a matter of fact, two motors will fit on a single 15 amp circuit.
===================
If you want to be proactive without committing to 240 volts, then have several 1-or-2 outlet circuits pulled with 20 amp (12 gauge) wire at strategic locations. If you change your mind, these circuits can be converted to 240 volts by swapping the circuit breakers without having to pull new wire. In the mean time, they are fully functional at 120 volts.

[Rick Christopherson]

I'd love to draw a picture here but I'm not up to it. ....

Bill, you were writing your reply at the same time I was writing mine, but you finished sooner. I believe the picture you wanted to draw is shown in my posting. (I drew it 8 years ago.)

[Bill Neely]

That's exactly what I was picturing and a better explaination. Thanks.

[Bill Lewis]

If you want to be proactive without committing to 240 volts, then have several 1-or-2 outlet circuits pulled with 20 amp (12 gauge) wire at strategic locations. If you change your mind, these circuits can be converted to 240 volts by swapping the circuit breakers without having to pull new wire. In the mean time, they are fully functional at 120 volts.This is exactly what I did with my shop. I made dedicated 20A 12/2 wire, circuits for the compressor, table saw, and dust collector. I wired the circuit for the contractors saw I had to be 120V20A initially. When I upgraded to the unisaw, I just changed the breaker and outlet to be compatable with 240V/20A. The reality is that even this is probably overkill. None of the motors have amperage ratings higher than 15A, so technically I could run them on 14/2, 15A circuits. Bigger gage wire will run cooler (note, I said the wire, not the motor will run cooler), and reduce voltage drop. My circuit runs are so short that drop is negligible.

I think this also begs the question, "Why are tools prewired for 240V?" I'd have to guess that one reason might be to allow them to run safely on a converted "house circuit".

BTW great response Rick, Richard, Jim and others. This debate (and the one on HP ratings for shop vacs) has been raging for as long as I can remember and it still comes up. I'll admit there was a time I didn't know the why either, and I can remember back around 1980 when it was first explained to me. I understood it, yet there was still some mystery surrounding it.

[Tom Jones III]

Amen to what Rick said. The only thing I have to add, I use 240 in my shop to get enough amperage to run tools simultaneously. Frequently friends will be over to help or work on their own projects and I often find the 3 HP TS and the 13" planer running at the same time. If these shared a single 20 amp 120 V line, then we would blow the circuit. The alternative is to run multiple 120 V circuits.

In fact, in my shop I've got white sockets that are 120V and used for the radio, fan, plug in lights, battery charger, etc. There are also 20A 120V grey sockets that are used for mobile tools and smaller stationary tools (MS, scroll saw, biscuit joiner, etc.) Then I have a big 240V that runs the jointer, planer and TS. There is a separate 240V circuit that runs the dust gorilla and the A/C. The overhead shop lights are on their own dedicated 120V circuit.

[Jim Becker]

Rick, thanks for clarifying the Delta motor thing...good to know it.

[Roy Wall]

This is a specific statement: Roy, I have yet to see a motor with that type of rating, with the exception of the mistakenly rated Delta motor.


Rick,
My brain was locked on the 11 amps....I meant to say 9 amps...

Here's an Oneida example between a motor wired 110 vs. 220.....

http://www.oneida-air.com/products/systems/1_5hp/specs.htm

I have the dust gorilla (2hp) and will run it off a 20 amp/ 230v circuit (Is that the proper way to say this...?) They told me the motor could run off 115v, but did not recommend it. It pulls 11.4 amps @ 220

Thanks for the info - I've copied it for reference!!

[Dev Emch]

This time, I need to agree for the most part with Rick. Just remember this...

Twinkle Twinkle Litte Star, Power Equals I Squared R.

Voltage and current conspire together to give you power which is conserved. Move one up and the other goes down.

As for motors, Rick is right. DUAL VOLTAGE motors have two windings which are either in series or parallel as noted. This equally applies to three phase duallies.

The only minor nit pick is this. In order to fit both windings into the stator slots, etc. motor makers often drop the gage of magnet wire used. Companies like baldor have a reputation to maintain so I would not worry about them. Louis Allis is simply put, BULLET PROOF. But other companies that use shootgun shack design and construction methods may give you issues at the lower voltages. This also has to do with "Duty Cycle". Its about the amount of heat that is generated and also dissapated. By using larger and heavy stator packs and fatter gage wire, you can remove the heat demon and run full out without any duty cycle issues. Note I have not mentioned voltage in the last sentence!

Wire moves electrons in a wird way. There is what is known as the coronna (sp?) effect in which very low amps will first move electrons though the outer most copper atoms in the wire. The inner most atoms are lazy and dont do anything. As the current goes up, the inner most atoms are now put to work. As more and more atoms in the cross section are motivated to transport electrons, more engergy is converted to heat. Finally, there is nothing more to motivate and the heat output now goes crazy burning the insulation and melting the wire.

All wire will output heat to some extent. That is how they determine the overall current load of say THHN wire stuffed into conduits. The number of conductors and the overall fill factor are based on both ease of installation and dissipation of heat. An EMT conduit will disspate more heat than say a PVC conduit. That is also why air bourne conductors are rated at higher ampacities than conduit housed or burried conductors are.

I think that this information was the source of the misinformation published in years past that has led up to the urban legends of 220 volt motors running cooler than 110 volt motors. My concern is this. Because I have stuffed the extra coils into the stator, I may be running a slightly thinner gage winding than I would normally do. At full namplate rating, this may cause the motor to run hotter. But this will happen irregardless of whether I am at 110 or 220 volts. This problem is most evident if your motor has a duty cycle of anything less than continous.

Also note that 110 volt circuits are limited to 20 amps for the most part. You just cannot buy a single pole breaker larger than that. This is also partially why you can use a reduced gage neutral. A 220 volt circuit which includes 240 volts is differential or 2 pole. So there is no neutral. Also please do not confuse a ground wire with a neutral. There are subtle differences between the two. Your breakers should be installed in a balanced manor. In other words, dont pile all the breakers into the box on just one side. The trick is to balance out the current flows in your neutral.

In looking at my stuff, anything less than about 5 hp is on 110 volts and all of my 5 hp or greater motors are 245 volts three phase. Many lathes have 1 and 2 hp motors and they are 220 volts. That is because they are also three phase and there is no such thing as 110 volt three phase power.

You have seen the numbers of 220 volts and 240 volts and 208 volts and 245 volts thrown around with wild abandan. Clearly there may be some confusion here. The 208 value is an industrial Y connected three phase power source. For home use, you will see 220 volts as the norm. But not all utilities use this. Some use 240 volts. Also, depending on how close you are to your main switching station, you may see minor variations in your line voltage. For example, my line voltage is a rock solid 245 volts.

So if your machines can run on either 110 volts or 220 volts, then I would not be too concerned to run them on 110 volts. If you see yourself going to say a 5 hp table saw, then I would include provisions for a 220 volt table saw circuit. Same applies to a drill press although I would like to see a drill press with a 5 hp motor! Must belong to shack O'Neil!

A bigger concern about wiring the shop is three phase. Now most of you guys are happy with single phase and as such, your designing your wire configuration accordingly. Some of you will, in time, change over to three phase vis a vis a phase converter. Have you made provisions in both your service and your box slot count to add in a converter at a later date? This is what I would be more concerned over.:D

[Dev Emch]

One more point.

If you use more than one machine at a time, you need to look at your total current load. For example, if your using a DC and a jointer at the same time or a DC and a table saw at the same time. Putting both of these on the same branch circuit which is very doable with a 110 volt circuit would not be a good idea. Here, the use of a dedicated circuit helps out. As motors get larger, it simply becomes easier to just use dedicated circuits for certain dedicated machines.

[Steve Clardy]

Also note that 110 volt circuits are limited to 20 amps for the most part. You just cannot buy a single pole breaker larger than that. This is also partially why you can use a reduced gage neutral. A 220 volt circuit which includes 240 volts is differential or 2 pole. So there is no neutral. Also please do not confuse a ground wire with a neutral. There are subtle differences between the two. Your breakers should be installed in a balanced manor. In other words, dont pile all the breakers into the box on just one side. The trick is to balance out the current flows in your neutral.

Dev. I have a 30 amp single breaker on the side of my house for a RV hookup.

Back to the topic, I run everything I can on 220. As far as power differnece between 110 vs wired 220, I'll not comment as I'll get bashed again. Lol
Steve

[Randy Meijer]

Rick: I enjoyed your article. Learned a few things, and unlearned a few others!! Thanks.

[John Bailey]

"If you want to be proactive without committing to 240 volts, then have several 1-or-2 outlet circuits pulled with 20 amp (12 gauge) wire at strategic locations. If you change your mind, these circuits can be converted to 240 volts by swapping the circuit breakers without having to pull new wire. In the mean time, they are fully functional at 120 volts." Rick Christopherson


This sounds like a good solution to me. As always, I learned a wealth of information from "Creekers." Thanks to all.

John<!-- / message -->

[Steve Stube]

Dev,
That is because they are also three phase and there is no such thing as 110 volt three phase power.


That is what I thought too, until I bought a 115v, 1 hp, 3 phase motor. Also bought a VFD 115v single phase input and 115v, 3 phase output to drive this motor. The combination runs fine. I didn't actually measure the voltage but that is what the tags say.

120 vs. 240 volt operation. I won't debate it with anyone but I will suggest that folks try their multi-voltage machines on 120v and on 240v. If you don't notice a difference, fine, use whatever voltage you like to feed that machine. If however you see a marked difference in performance running on 240v over the 120v (as I have on some machines) then I suggest you power it with the 240v. I see several posters have said it cost the same on either voltage (IR losses not being totally evaluated, IMHO) so why not run it on the voltage that makes it run best.

The original question, John, if I recall you have pretty much decided where machines will go in your new shop. If you already have these machines, then you could experiment (as above) and you are correct,
110/220 machines are easily switched. I didn't know what would be where when I wired my shop and I don't think it will stay the same anyway as equipment changes so I wired it for the case where the placement of equipment would be fluid as much as I could. I have wired outlets every 4' along all walls, (both upstairs and downstairs) where possible, with every other one being 220v and the rest 120v. For this I used 12 - 2wG for the 120 and 12 - 3wG for the 240v. I also have a number of drops from the ceiling in 20 amp 120v, 20 amp 240v, 40 amp 240v and 4 welder outlets near exit doors downstairs that are 60 amp 240v. I put in a separate 40 amp ckt. for the air compressor under the stairs. GFCI 120 v receptacles outside at each of the 4 doors on the ground level. I split the ckt's. such that it is near physically impossible to operate two machines on the same circuit at the same time. There is at least a 14' separation between outlets on the same ckt., most are 28' or further. I know our shops are quite different but perhaps (hopefully) something I've said will be of help in your electrical planning.

[Rick Christopherson]

Dev, once again I am left scratching my head regarding the applicability of one of your dissertations. This is now the third time you have stated that you don't agree with something I have said, yet you don't say what it is you disagree with, or substantiate why you don't agree with my information.

As I surmised in a previous discussion, you have actually argued points that we are both in agreement on. This I find the most confusing.

That being said, I am kind of reluctant to say this for fear of leaving you (and others) with the wrong impression, but I do have to take issue with some of the information in your posting. Please don't think that I am deliberately being argumentative, but if you write as an authority, the information needs to be sound.

I apologize in advance if any of what I say below sounds argumentative. I have tried very carefully not to carry a negative tone.
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You stated: In order to fit both windings into the stator slots, etc. motor makers often drop the gage of magnet wire used.

It makes no difference if the motor is dual voltage or single voltage, it will still have the same number of turns in the windings, all other things being equal. The wire gauge is a function of the current the windings are expected to have. And the current is a function of the number of turns in the windings, as this dictates the resistance and impedance of the coils (for a given frequency and voltage).
=================================
You stated: There is what is known as the coronna (sp?)effect in which very low amps will first move electrons though the outer most copper atoms in the wire.

First off, there is no such term as a "Corona Effect". What you are referring to is the charge density as described by Gauss's Law, however you have mistakenly assumed this applies to current density.

The current density for a conductor will be uniform throughout its entire cross section. If this were not true, then we would have wire ampacities that were dependant on the shape of the wire (surface area). Furthermore, the resistance of the conductor would also have to be dependant on the shape. The resistance of a wire is equal to its resistivity times the length divided by the cross sectional area (roe x L/A). The surface area has nothing to do with the current density or the resistance of a conductor.
=================================
Finally, there is nothing more to motivate and the heat output now goes crazy....

Heat generation is the result of electron collisions with the atomic lattice of the conductor. There is no mythical break-point where heat is suddenly generated, and below it there is no heat. This may make more sense if you consider superconductors.

The concept of superconductivity was first discovered with materials near absolute zero (0 degrees Kelvin). At these temperatures, the atoms in the conductor do not vibrate, and therefore do not collide with the conducting electrons. No heat is generated, and no resistance exists.
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This is also partially why you can use a reduced gage neutral.

You cannot use a reduced gauge Neutral!!!

You are confusing the information I posted in a different thread. Just because balanced loads on a 120/240 volt system (or a 120/208 volt 3-phase system) will cancel out the current in the Neutral, does not mean you can reduce the size of the Neutral.

The neutral is still a current carrying conductor, and as such, it must be protected by a circuit breaker of appropriate size. The circuit breaker on the hot leg serves this purpose. If you reduce the size of the Neutral, then you must reduce the size of the circuit breaker (on the hot leg) accordingly to protect the wire. The breaker must be sized to protect the "weakest link" assuming that not all conductors are of the same size.
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In looking at my stuff, anything less than about 5 hp is on 110 volts...

This may be considered nitpicking, if so, I apologize; but in order for a 5 hp motor to operate at 120 volts would require a minimum of 40 amps. The largest motor that can be operated from a 20 amp, 120 volt circuit is about 2 horsepower.
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...there is no such thing as 110 volt three phase power.

I know that I'm being nitpicky here, but it is misinformation nonetheless. A wye configured 3-phase system does in fact provide 120 volt 3-phase power. Just like its single-phase counterpart, the 120/208 volt 3-phase system delivers 120 volts phase to Neutral.

Furthermore, the voltages you threw out with wild abandon, are just that, Wild Abandon. The drawing below shows some of the common voltage sources used in the United States.

http://waterfront-woods.home.att.net/tempgraphics/y-y-system-lo.jpg

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In several of your past threads, you have provided some extremely informative discussions (off topic or not), and I have great respect for that. However, the misinformation you have presented in this thread has left me with some serious doubts about your credentials.

I am not infallible and I do make mistakes with information, but your last several paragraphs really have me troubled. If you are going to carry yourself as an expert, you really need to take extra care to make sure the information is accurate.

[Kirk (KC) Constable]

I love threads like this. :) Despite Rick's very technical explanation, which he can obviously back up with authority, and which has been posted many times on many forums, the next time someone asks the question...which could be tomorrow, the same wide array of misinformation will be repeated. I'm really not sure why he keeps trying. :(

KC

[John Bailey]

I have thoroughly enjoyed all the posts, although the technical explainations (and some of the non-technical explainations) have long since passed well above my head. However, all the information has been great, even when there is a passionate disagreement. The disagreements allow me to make an informed decision with knowledge from both camps of info. This will lead to a good practical solution that will be my responsibility to make work in my shop.

As for my new shop. It's going to be small by many standards (20x20) but perfect for me. My heavier machines are going to be small by many standards because I enjoy hand work and the machines will be there to compliment the handwork. I do know where the machines will be with an alternate spot for the jointer and planer. So, with this info, I will be able to plan accordingly.

Again, Creekers have risen to the occasion and provided excellent information that gives me great confidence that I will make the correct decision for me, in my new shop.

Thanks to all,

John

[Richard Wolf]

[QUOTE=Rick Christopherson]Dev, once again I am left scratching my head regarding the applicability of one of your dissertations. This is now the third time you have stated that you don't agree with something I have said, yet you don't say what it is you disagree with, or substantiate why you don't agree with my information. QUOTE]



Rick, You have a total of 9 posts and Dev has only disagreed with you 3 times, odd!

Richard

[Mike Weaver]

Rick, You have a total of 9 posts and Dev has only disagreed with you 3 times, odd!

Richard

Richard,
At the risk of offending some for bad humor...

That's easy to understand - Dev is 3 phase!:eek:
He gets 3x the points per 'leg'.

Sorry, i couldn't resist...:)

In all seriousness, and even though some of this stuff is way over my head, I have enjoyed reading all of it.

SMC truly is a great place!

Cheers,
-Mike

[Ed Breen]

Like many of the others, a lot of what was said went over my head. However, I am printing this thread for later thought. When I powered m,y shyop I started with 200 amp. service. On the north wall I have 4 110 outlets in a strip and 1 220 next to the strip. All use 20 amp breakers. On the south wall I only ran the 110 strips every 5 feet. I run a 5 hp 3 phase for my grizz and a 2hp 3 phase for my ancient shaper. I can move my toys around and always have service ready.

Ed

[Dev Emch]

Rick...
With all due respect, I stand behind my disagreements. Clearly you do understand much of what has been posted. But I would not disagree unless I could back it up.

First of all, I think this topic is of great importance to the woodworking community; however, it can easily digress into full electrical engineering. When that happens, I see eyes glazing over.

Yes, there are both wye and delta three phase systems. For the most part, the home shop with its phase converter will not see that. The 208 three phase diagram works only on grid supplied power. DO NOT ASSUME THIS TO BE THE CASE WITH A PHASE CONVERTER!!!!! In some 208 machines, there are single phase items that are fed off of the 120 volt legs. You see more of this in metalworking than woodworking machines and if your not careful, you may burn out control transformers. I am currently rebuilding a hardinge lathe control panel board that had this very thing happen to it.

When you look at the hubble catalog, you will not find any twist lock three phase plugs for voltages less than 208, 3p. But there is nothing stoping you from using transformers to drop this lower. So oddity devices can exist and often do. The same applies for two phase power. On older machines, its not uncommon to find 2 phase motors. On some wood shapers, you will also find motors designed to run on 120 cycle power. Here you need a freq to drive them. I have seen only one oliver 287 like this and several whitneys and newmans.

For those using phase converters, please take notice. If you measure the voltage from L1 to neutral and L2 to neutral, you will find 120 volts. If you measure L3 to neutral, you will find aproximately sqrt(3) times 120 or about 204 volts. This is why the 208 wye diagram can be considered dangerous. If you dont know this, it can create a world of hurt.

Now I feel I need to defend myself a bit but this comes at the risk of scaring off potential users of vintage industrial machines which I would rather not do.:mad: Many vintage machines are direct drive machines with louis allis motors. You cannot replace these motors as they often have no ball bearings and their housings are integrally cast as part of the machine. The cutter shaft is supported by very precise bearings often being of ABEC 7 or better quality. The motor rotor is cantelevered off this shaft and hangs within the stator. The stator pack can actually be removed with ease. With most motors, I have to use a massive Dake press to do this.

So, what happens if I loose a motor? I have had to learn how to rebuild my own motors. So I do the whole nine yards including bake outs, modification of stator packs, repair of rotors and last but not least, rewinding of stators. Having my own machine shop helps. In examining surplus "import" motors, I found many of the reasons why louis allis is the motor to have! In terms of wire gage used, Rick needs to reread my caveats pertaining to "DUTY CYCLE" and the fact that baldor does not reduce gage size. But many makers do. Often, if you find a change of gage in motor, its because the motor was rewound for a new voltage. You will find that duallies with continous duty cycle are fatter or larger than duallies with say a 1 hour duty cycle. Ever wonder why?

There are some wood lathes about with really fat motors which are the headstocks. Yates and oliver among others made these. These motors actually have multiple windings which are connected together in different combinations to obtain various speeds. This is done at a special switch. These motors vary the pole count by changing the stator coil configuration at run time. All that extra winding needes more space!

So, to keep a duallie the same size, something has to give. And its often the gage size which ultimately reduces the duty cycle. Note that you can still use either voltage.

I have also done work on converting large induction motors into sycnronous alternators. This was done using salient pole, wound rotors which replaced the original induction rotor.

If any of you really wish to get into motors, I would suggest picking up these two books for starters.

1). Armature Winding & Motor Repair by Daniel H. Braymer.
2). Electric Motor Repair by Robert Rosenberg. (This is considered the bible of electric motor repair).

I was offered the chance to use a "Reduced Neutral" on my new service installation by the inspector. For a domestic house, this is an option. For a commercial shop, I felt this was not an option esp. given the issues I have had in the past. Therefore, I declined to use a reduced neutral and kept my neutral the same size as the main service lines.

So yes, you can use a reduced gage neutral. But I sincerely hope that we are all on the same page here. The term "reduced gage neutral" applies to the conductor spanning the distance from your pole pig or transformer to your service center. IT DOES NOT APPLY TO THE WHITE WIRE SPANNING YOUR RECEPTACLE, FOR EXAMPLE, TO YOUR SINGLE POLE BREAKER!

When one looks at heavy gage wire, you will see that its braided and not solid. This serves not one but two purposes. First, it does make it easier to use. Second, it optimizes the electron transfer in the wire by forcing electron flow to the surfaces of multiple strands. Electrical engineers have known this for years. In fact, if you go to the HI FI shop, they will sell you monster cable for hooking up your speakers. Its very expensive super fat, multi stranded cable. I will admit its a bit of overkill for speakers but its based on the same premise of forcing the electrons to flow more towards the outer surface of the wire then through out its entire cross section.

Also note that resistance is a product of both the material of the wire and its geometry. RESISTIVITY is a material property. Copper has a different resistivity than does aluminium or gold or iron. So I can change the resistance of a conductor by either using a different metal *OR* by changing its geometry.

Lastly, Rick did claim that the reason for using run caps in a phase converter was to energize the third winding of the idler motor. This is as I have already mentioned, flat out wrong. Not only did my first converter not need run caps, but I can show you a commercial example proving this as well.

My current coverter is a kay converter. It has some unique features that allow it to run CNC based three phase machines such as CNC lathes or mills etc. That aside, upon opening it up, I noticed some unique things. If anyone wishes to have a photo of the guts of this converter, just email me.

First of all, there are no start circuits. No voltage relays and no electrolytic caps. Unique changes in the rotor design allow it to start with greater ease. And here is proof that you dont always need run caps.

There are two banks of oil filled run caps which are hooked up via a square D relay. The pull in coil of the relay is driven by an ABB current sensor module with a hall effects sensor on the wild leg output of the idler motor. On heavy start up or load up, the current flow in the wild leg trips the ABB sensor thus bringing the run caps online. Under nominal conditions, the run caps pop offline and are *NOT* needed to generate three phase power. The thrid winding creates the wild leg through magnetic field coupling and rotation. The sole purpose of the run caps are to maintain voltage level balance. And in many cases, the imbalance is only significant during start up and immediate load conditions.

So I stand by all I have said. And the proof is in the pudding.... there isnt much industrial stuff I have not run including planers, lathes, milling machines, table saws and very heavy duty shapers.