Starcool 20 amp ac circuit has 4.5 volts with breaker throw (?)

[batgirls]

Hi,

I’m troubleshooting electrical issues on our 92 Ford EB sportsmobile

We added two LiFePhosphate batteries and a dc-to-dc charger to intake power from the alternator and on board transformer that is plugged into shore power.

We protected against backflow with diodes and a marine switch (no input, alternator, shore power theough transformer).

The DC side-propane detector and lights are working fine. The fridge does not work, but it did with the lead acid house battery.

The AC side has some apparently dead breakers, which i’ll replace tomorrow. The 30 amp main is ok. Both 15 amp breakers (fridge, transformer and other power) aren’t passing current when on or off.

The starcool breaker passes 121.5 volts when on (same as the main breaker). But when it is off, it has 4.5 volts on it.

Is this normal? Do we have a leak from dc/house battery to the starcool (theoretically we shouldn’t)? Does van’s 12 volt system continuously power it?

Thanks for advice/ideas :-)

[Twoxentrix]

Do you have any 110v GFCI outlets? One of them may have tripped - if you do have these, I would suggest checking each by pushing the reset 'in' just to confirm.
In your process of changing and/or adding electrical components you may have tripped one and not realized it...ask me how I know

Other than knowing not to hold both neg & pos wires in my hands at the same time, I'm unable to offer any other advise - but others here will chime in i'm sure.

[batgirls]

Thanks Twoxentrix,

All of the 120 outlets are gfcis. I’ll check them after i replace the circuit breakers.

Ben

[Scalf77]

In most cases the 15 amp breakers go directly to a GFIC, then on to additional outlets. So I would check the GFIC before changing out the breakers. To reset the GFIC, you will need to make sure there is voltage present. So on shore power main breaker on, and subsequent 15 amp breakers. The 20 amp breaker for Starcool II is direct, no GFIC involved. 12 Volts is always present at the Starcool relay board.

Starcool II Manual

[batgirls]

Thanks for the link to the starcool manual scalf77. That will be very helpful.

Good to know there is alway voltage on the starcool.

Thanks!

Ben

[Big_ern_101]

Disconnect the Starcool from the breaker and retest your voltage. Highly unlikely that the breaker is leaking voltage, most likely the starcool is the source.