Hello,
I have a Heart Interface Marine 20 on my Cat 36 mkii, yesterday it began tripping the charging circuit breaker on the power panel. I reset it and it tripped again in about 5 minutes. From the research I have done on google I'm going down today and check the shore power voltage, and go through the trouble shooting section of the manual. However, have any other members had a similar problem? I imagine this unit came with the boat which would make it about 15 years old, and I wonder what is the life expectancy of these units?
Kind Regards,
Gary
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Gary Johnson
1999 Cat 36 mkii, M35C
Hull # 1755, Fin Keel
Homeport: Long Beach, California
There's not much that will trip the charging circuit breaker other than an internal fault. Yup, make sure the shore power is indeed 120 volts. Low input voltages can sometimes tip breakers as current demands sometimes go up to satisfy the power output demand. Not common though. High input voltages usually zap something.
The fact that it takes 5 minutes to trip might indicate the cooling fan is not running. You might try disconnecting the batteries and see if this extends the trip time. If it does extend the trip time, then cooling becomes highly suspect. You might be able to visually observe the fan through the grills or hear it operating. 15 years is a LONG time for a cooling fan.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Thank you Nick I will try that also. I can hear the fan running until the circuit breaker trips. I'm also going to check the condition of the batteries tomorrow when I go back down.
Gary
Gary Johnson
1999 Cat 36 mkii, M35C
Hull # 1755, Fin Keel
Homeport: Long Beach, California
What I have been able to figure out so far is that the power share was set to 50 amps and was tripping the 15 amp charging circuit breaker. Not 100% on that but when I have it set 5-15-20 or 30 it does not do it. In the meantime I now have to replace the house batteries, they were in the boat when I purchased it so I really do not know how old they are. But when the circuit breaker tripped last week the refrig totally drained the batteries over a 5 day period. I was going to replace them anyway now a little sooner than later.
Gary Johnson
1999 Cat 36 mkii, M35C
Hull # 1755, Fin Keel
Homeport: Long Beach, California
It sounds like you have the optional Remote Control and this might help in any diagnosis.
It's not unusual for the refrigerator to flatten batteries very quickly. In warm climates, about 75 amp hours per day. In 5 days, you could draw down two healthy
4D's in parallel pretty deep.
Finally, please consider editing your signature to include boat year, engine, keel, rig, and cruising area. Certainly optional, but nice to know stuff.....
Nick Caballero
Retired C36/375IA Mk II Technical Editor
If you look at the attachment the Inverter/Charger has one circuit breaker on it rated at 25A, the power panel has another rated at 20A. Yes the inverter has a remote that has the power share function.
BTW, thank you for your help.
Gary
Gary Johnson
1999 Cat 36 mkii, M35C
Hull # 1755, Fin Keel
Homeport: Long Beach, California
Perhaps a eureka moment here. The single breaker on the Marine 20 is rated for 25 amps. This is the maximum allowed AC amps draw when the charger and transfer functions are engaged, i.e, when you're plugged into dockside power.
The Power Sharing feature is designed to reduce the AC power available to the charger when the needs of the charger plus other AC loads (water heater for example) threaten to exceed the rating of the breaker, essentially giving priority to non-charger AC loads. According to the manual, the Power Share settings should reflect the capacity of the boat AC system, which is 30 amps.
When it was set for 50 amps, Power Sharing was not limiting the AC amps at all. The breaker was likely tripping because you were trying to charge deeply depleted batteries concurrent with some other significant AC loads. Lowering the Power Share setting to 30 amps or 20 amps tells the Marine 20 to limit the allowable combined power draw more in line with the 25 amp breaker.
I think problem solved!
Nick Caballero
Retired C36/375IA Mk II Technical Editor