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Any thoughts on running powermatic 3520b and air compressor on a generator?
New leased space lacks 220v power.
Thanks.
Dave
New leased space lacks 220v power.
Thanks.
Dave
Any thoughts on running powermatic 3520b and air compressor on a generator?
New leased space lacks 220v power.
Thanks.
Dave
2. I'm not sure this is legal or smart but several local chapters and a regional symposium use this and
I have seen electricians run similar things at symposiums. You can run two 110 separate circuit outlets into a 220 plug.
Basically they use a sort of extension cord with two wires and 110 plugs leading to one 220 outlet.
Two 110 cords plug into the wall outlets on separate circuits.
Not sure what goes into the box with 220 plug. Might be a shock hazard if one plug is plugged in the other might be hot.
I have done quite a few demos on powermatics plugged into these two wire devices.
You might ask an electrician if one of these can be used .
Al
The 2-circuit-into-one is used provided you can identify two distinct circuits. Since you will have more that one outlet to a circuit, you'll have to do some "circuit mapping".
OK, I can see that I won't be asking either of you guys for electrical wiring advice. And I certainly would bestow the title electrician to anybody committing that sort of haywiring.
What both of you are talking about means that you already have 240 VAC service anyway. Typical 240 VAC power is supplied as what is known as split single phase. This means that is it 240 VAC with a center tap that becomes the neutral for two 120 VAC power legs that are 180° apart referenced to the center tap. In typical residential wiring that is supplied by this type of power, electricians commonly refer to the two 120 VAC hot legs as AØ and BØ power. The center tap is the neutral wire for both of these phases. Branch circuits that require 240 VAC are simply connected between the two hot legs and the center tap is not needed (except for ovens, ranges, dryers, and sometimes HVAC systems that require both 240 and 120 power).
So the bottom line would be if the building truly only has 120 VAC power then you can't play games with branch circuits to conjure up 240 VAC power. If that were not so, why in the world would we ever bother using transformers?
Now, on the other hand suppose that the building really is being fed with 240 VAC power where all of the branch circuits are 120 VAC with about half on the AØ and half on the BØ, but no dedicated 240VAC branch circuits -- then:
- Why not do it right since you already have 240 VAC and just add a dedicated 240 VAC branch circuit.
- Regrettably in this situation where things could be done right it is possible to do it wrong by jack-leg wiring two opposite phase 120 VAC circuits. Why is this a bad idea? It creates a very real safety hazard for electrocution. There are numerous problems, but I'll only mention the one that ought to be obvious to anybody -- an over-current or other fault condition that causes one breaker to trip will result in the connected equipment still being "hot" (exposed to high voltage). A proper over-current circuit has both hot legs mechanically ganged together so that any fault on one leg causes both sides to trip. The jack leg arrangement lacks that sort of protection.
Nobody mentioned the need to have the generator outside. I'm assuming it runs on gas (which of course costs money) and generates Carbon Monoxide. so he may be killed by that before he gets electrocuted.
Safety first.
I will add that I have used my generator to power my 3520b when doing a demo in an area without 220. This was for a few hours, and so far no noticeable effect on the VFD. Worry about the supplied voltage made me keep a couple of incandescent lamps on the whole time to help knock off voltage spikes. The auto idle feature was kept off also to keep the cps near to 60 and the supplied voltage as stable as possible. The generator used was the common constant rpm alternator style, not the newer 'quiet' style that increases rpm as demand increases. I believe the newer quiet style uses a style of VFD to change the output of the generator to 60 cps current.
OK, I can see that I won't be asking either of you guys for electrical wiring advice. And I certainly would bestow the title electrician to anybody committing that sort of haywiring.
What both of you are talking about means that you already have 240 VAC service anyway. Typical 240 VAC power is supplied as what is known as split single phase. This means that is it 240 VAC with a center tap that becomes the neutral for two 120 VAC power legs that are 180° apart referenced to the center tap. In typical residential wiring that is supplied by this type of power, electricians commonly refer to the two 120 VAC hot legs as AØ and BØ power. The center tap is the neutral wire for both of these phases. Branch circuits that require 240 VAC are simply connected between the two hot legs and the center tap is not needed (except for ovens, ranges, dryers, and sometimes HVAC systems that require both 240 and 120 power).
So the bottom line would be if the building truly only has 120 VAC power then you can't play games with branch circuits to conjure up 240 VAC power. If that were not so, why in the world would we ever bother using transformers?
Now, on the other hand suppose that the building really is being fed with 240 VAC power where all of the branch circuits are 120 VAC with about half on the AØ and half on the BØ, but no dedicated 240VAC branch circuits -- then:
- Why not do it right since you already have 240 VAC and just add a dedicated 240 VAC branch circuit.
- Regrettably in this situation where things could be done right it is possible to do it wrong by jack-leg wiring two opposite phase 120 VAC circuits. Why is this a bad idea? It creates a very real safety hazard for electrocution. There are numerous problems, but I'll only mention the one that ought to be obvious to anybody -- an over-current or other fault condition that causes one breaker to trip will result in the connected equipment still being "hot" (exposed to high voltage). A proper over-current circuit has both hot legs mechanically ganged together so that any fault on one leg causes both sides to trip. The jack leg arrangement lacks that sort of protection.
Bill,
Most folks, me included, get a little fuzzy between neutrals, earths, and grounds since they usually all go to the same place. Your post seems to indicate that 220 doesn't need to have that third wire which I'm pretty sure isn't what you mean. Never had 220 without the neutral or ground or three phase without the fourth wire. ....
Bill although I am not a certified electrician I have extensive electrical knowledge and every this you say is 100 % accurate and nicely explained
Hu as bill said there is no need for a neutral wire if all that is required is 220V ie a Lathe because there is no 110V requirement so 2 insulated conductor plus a bare ground wire and as Bill mentioned your dryer need 220V for the heating element and also needs 110V for the motor and electronics or timer 3 insulated conductors plus the ground
What do you think about deciding (only as a last resort) to substitute a nova for my 3520b and go to a 110v compressor?
for the replies. I especially appreciate the part where John Lucas recounts the order of hazards leading to various causes of death--although you all missed the probability that I could die even earlier from the heart failure from reading this thread or the stroke from laughing too hard!!
Seriously, if I am lucky, the builder will have pulled underground conduit from the panel to the detached 2-car garage where my shop will be. If no such conduit, my guess is that the price to rip up driveways, shrubs, sidewalks, etc, will be prohibitive.
What do you think about deciding (only as a last resort) to substitute a nova for my 3520b and go to a 110v compressor?