WIRING QUESTION.

[rjack321]

Neutral to or through the case does not sound good (or code compliant) at all.

 

[NAM001]

If all you have coming in to the case for 240V is two leads then both of them are hot. There is a missing neutral. I would recommend hiring an electrician to do this job. It already sounds like it isn't up to code. You don't need a transformer to step 240V down to 120V, you can tie into one leg and the neutral and you'll have a two wire 120V circuit.

that is the other option I am considering. thanks

 

[NAM001]

I’d run two identical fans is series

this is for a fan to sit on top of the comprerssor to give extras cooling from a 21 inch house fan. I wanted to pt a timer onthe outlet to let the fan run for a while after the compressor shuts down.

 

[NAM001]

I reread the initial post and using the case for a neutral is NOT allowed. Yes they used to do this with electric clothes dryers but no more, for the simple reason being it could float to potential if the ground is compromised or disconnected. What Mr Wookie is saying about high leg is usually in a commercial building. I have dealt with it when someone decides to put a restaurant in a sorta residential area and the power company is on the cheap and fast answer mode. If a high leg is there it MUST be marked as such.

I have worked with many industrial wiring and ship wiring in the past and what I was seeing is a system like on a ship developing and that was not good in my opinion where the 120 outlet had 60 vac on each leg. 'Every thing was floating ground. The old wiring for the compressor had 2 lines going to it for the 240ac and a green GROUNDING line. think I need to change that to 2 hots and a neutral and then tap half for the 120 outlet. Much like a home dryer . that will be easy to do. Thanks.

 

[NAM001]

From what I have read,,,the simple option, assuming, and we all know what that means,,,he has just 240 v coming into the controller, would be purchase a 240 volt fan. Yes they are made and would stop the addition of a transformer, rewiring, and additional controls. The fan would add a small amount of current on the load side and not affect the compressor operation. Assuming, yes here we go again, it is not a large commercial fan. Keep it simple and you should not need an outside electrician to overcharge and do a major renovation on the controls or feeder.

To find a 240 fan would be the simplest. Right now I have a2 hots and a grounding lead coming from the panel. the grounding and neutral are electerically the same in my panel . I donot have a neutral bus and a grounding bus. they use the same strip as they are tied together.

 

[rjack321]

To find a 240 fan would be the simplest. Right now I have a2 hots and a grounding lead coming from the panel. the grounding and neutral are electerically the same in my panel . I donot have a neutral bus and a grounding bus. they use the same strip as they are tied together.

From the panel to the street neutral and ground are tied together

From the panel to your controller and then again from the controller to your device you need to separate the neutral and the ground. Or you end up having a compressor and fans with no actual neutral and its return is ground.

 

[PBcatfish]

To find a 240 fan would be the simplest. Right now I have a2 hots and a grounding lead coming from the panel. the grounding and neutral are electerically the same in my panel . I donot have a neutral bus and a grounding bus. they use the same strip as they are tied together.

Per NEC, ground only bonds to neutral at the service entrance. Bare wires & green wires are on the ground buss. White wires are on the neutral buss. Yes the two busses are connected by a bonding bar, but you should not have white wires on the same buss as a green or bare wire. If you do, then your box is probably not wired to modern code. No you are not allowed to connect a neutral load wire to a green or bare wire that goes to a ground buss (even though it will usually make the device function).

240vac fans are available, especially if you are looking for a little square one like they use on computers. Some have locked rotor sensors that can be used to shut down the system in the event that the fan fails.

If you currently have a 3-wire 240vac feed that has 2 hots & a ground, another option would be to change to a 4-wire plug that has 2 hots, a neutral & a ground. This would require adding an appropriate outlet. The existing breaker in the box should still be acceptable. You are just adding one additional wire that goes to the white wire buss.

If you add a stepdown transformer, the wiring rules change depending if it is an isolation transformer or an auto-transformer. They are very different animals. Know what you have before you wire it.