[jclark003]

So you have traveled to multiple marinas and seen the same problem? And you are tripping the pedestal breaker and not be ships inlet breaker? If so I would first suspect your cable end and or receptacle (depending on whether you have a cablemaster). If There isn't a good connection, arcing will occur between the cable end and receptacle creating a much higher amp draw (and fire hazard). If the prongs in the cable look burnt or the cable ends get hot After a sustained medium load then you may want to put a new end on or get a new cable. .

Do you know if your ship is equipped with an isolation transformer? If so I wouldn't be surprised if a short in the transformer windings can cause the same problem.

if your not experienced with AC electrical gettting a professional to help may be money well spent. Most boat fires are due to shore power connection issues, not to mention the inherent danger of electrocution from high voltage.