Tapping 110v from 220

[shell70634]

I'm planning the replacement of my air compressor. I'm adding a homemade cooling system between the compressor and tank. The fan requires 110 volt. I have 220 volt at the site for the compressor motor. I really don't want to run another 110 circuit and thought I might tap into one side of the 220. Good idea? Bad idea? If it's unsafe or not advisable for other reasons I will search for a 220 fan motor for the cooling system. The compressor is outside the building under cover with the switch inside the building. Making everything run from one switch is preferred.

 

[SLK001]

It depends on the wiring for the 220V. Some 220V wiring has 4 wires - two hot, a neutral and a ground. With this config, you can easily tap off 110V. If you only have three wires, two hot and a ground, you can get 110V from a hot and the ground, but I believe that this violates all electrical codes. Your better option would be to simply get a 220V fan.

 

[markba633csi]

You can use a hot and ground to get 110v- I won't tell anyone
For a light load like a fan it should be fine

 

[Winegrower]

There are some pretty inexpensive down converters on eBay, depending on the power you need. That could be effective.

 

[epanzella]

My lathe is 220 but the lights over it are 110v. I just fed the lights with one leg of the 220 line. Lots of appliances do this right from the factory. An electric range uses 220 for the burners but one leg of 110 to power the clocks, timers, lighters, ect. If you have a large 110v load it would be best to split it up over both legs of the 220 line but just make sure that neither leg is driven over the capacity of the 220v breaker which is merely two 110v breakers slaved together so if one trips it takes the other one with it.

 

[rabler]

For this reason, I run 4 wire for 220V circuits even if I only use a 3 prong receptacle, I leave the unused neutral wire capped in the box.

 

[rwm]

Am I mistaken on this but are some ground wires smaller in gauge than the conductors in the same cable?

 

[matthewsx]

For this reason, I run 4 wire for 220V circuits even if I only use a 3 prong receptacle, I leave the unused neutral wire capped in the box.

This^^^^

If you do it with the ground you will forget, or not be around some day and someone can make a very bad mistake.

I have my shop wired this way through an extension cord, if you don’t have neutral please use a transformer. Just because something works doesn’t make it right.

John

 

[woodchucker]

Am I mistaken on this but are some ground wires smaller in gauge than the conductors in the same cable?

they are supposed to be the same size or bigger.

 

[woodchucker]

This^^^^

If you do it with the ground you will forget, or not be around some day and someone can make a very bad mistake.

I have my shop wired this way through an extension cord, if you don’t have neutral please use a transformer. Just because something works doesn’t make it right.

John

not if you split it off at the compressor. Then it's part of the compressor.