110 circuit problem

Jwhy

.
Feb 11, 2013
98
Catalina 320 Kilmarnock
When connected to shore power I’ve always had to limit load that would trip the circuit breaker serving the 110 outlets. So I couldn’t run the microwave and coffee maker at the same time. Not a big problem.

Years later I found that just operating the three original dehumidifiers simultaneously tripped the main breaker for the entire 110 circuit. A marine electrician determined that one of the dehumidifiers was bad and we found that disconnecting it solved the problem. We also replaced the main panel master switch circuit breaker and 110 circuit breaker. The electrician said it was probably time to replace the entire 1990 electrical panel.

Recently I found that virtually any 110 load trips the master breaker.

Is time to replace the panel or is there something else to track down?
 

Jwhy

.
Feb 11, 2013
98
Catalina 320 Kilmarnock
Good point! There is one on the boat. The other five are 30 year old standard outlets. Should they be replaced with GCFI?
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
Maybe it's the main breaker just getting old and needs replacement. Any ammeters in the circuit ?
 
May 1, 2011
4,189
Pearson 37 Lusby MD
The other five are 30 year old standard outlets. Should they be replaced with GCFI?
Usually, there is one GFCI for the outlets to port, and one for the outlets to starboard. On my boat, I have a GFCI mounted over the engine that feeds the microwave in the port side galley, and an outlet forward to port. The second GFCI is on the starboard side in the head. I have no other outlets on the starboard side.
 
Oct 29, 2012
346
Catalina 30 TRBS MkII Milwaukee
Check that the terminations on the breaker and power cord inlet are properly torqued are free of corrosion
 
Oct 29, 2012
346
Catalina 30 TRBS MkII Milwaukee
Could be a bad GFCI plug. Had that happen to me a few years back.
Should only trip the GFI not take out the main breaker....
Main breaker could be faulty from abusing the system by operating at or above it's rating. The breaker should be rated for 80% of the full load current