Cooling Fan not working

[Jamiek]

The cooling fan in our converter box where the breakers are is not running and is causing the a/c to trip.  Any ideas on how or what i should do to get the fun running.  The box gets very hot and starts to smell like burring rubber right before the a/c trips

[PattieAM]

My WFCO owners manual says that the Automatic cooling fan only operates under high load conditions - normally not during sleeping hours or when power demand is low.

It has an electronic current limit - which automatically shuts down power during overload or short circuit conditions.  It will return to normal after condition is corrected (alleviates replacing fuses and/or resetting circuit breakers).

You might see what your converter's owners manual states, and maybe find their web-site for more information.

If your breakers are tripping when using the AirConditioning, you might want to check for a short or loose connection.  Your airconditioner has a dedicated line/circuit and your PUP must be plugged into 30amp.

[mike4947]

The fan is to cool the transformer/rectifier that converts 120 volt AC to 12 volt DC.
It does nothing to cool the circuit breakers. It's not running because the actual circuits it's there to cool are not producing any heat to make it run.
What you have is a problem with the 120 volt. A loose connection at the shore power cord connection or a loose wire from the 20 amp circuit breaker to the wiring connected to it going to the roof top AC. Or a loose connection inside the air conditioner itself. A loose connection causes resistance, which causes heat. Get a circuit breaker hot enough and it will trip at less than it's rated loading.
So first start by checking those connections.

[rccs]

I'll second what mike4947 said. Your best bet would be to start right at the A/C and check where the power cord makes its connection and work your way back through all the wiring to the converter. Check all screws that make any connection to the power circuit to the A/C and make sure they are tight. Any of them that are loose will cause a problem with the breaker tripping to easy.