Originally Posted by PrairieBoy
GFI - Ground Fault Interrupter
Ground fault interrupters are designed to protect from electrical shock by interrupting a household circuit when there is a difference in the currents in the neutral and hot wires.
RVs usually trip these circuits that are protected by GFIs
Thanks for that, I understand now and yes its connected to one, I call them breaker trips.
Its never tripped it before and I run my mig welder through the same circuit, I will try the battery check and then start looking for shorted / bad earthed wires