Parallel combiner slow cut out

[RTagg]

I am using the parallel battery combiner function. When I start the engine it sends a parallel signal to the engine battery relay after 30 seconds as it should. When I stop the engine it keeps the engine battery in parallel with the house for a few minutes before disconnecting. Should it not disconnect immediately upon the engine stopping? Thank you.

[Coulomb]

It drops out when the voltage on the house battery no longer is high enough to be charging. That voltage won't fall immediately, depending on the load.

[RTagg]

Thanks for your response, that would make sense.

[RTagg]

Hello Coulomb, At what point should the relay open and the engine battery be isolated? I'm concerned that if there were a fault with the engine battery then the house battery would just keep charging it indefinitely? Thanks.

[Coulomb]

It drops out when the charging voltage drops below about 13V.