B2B charger and mains charger interaction?

[Travelling Westerly]

Probably a silly question but here it is anyway

The B2B charger is operating when the engine is on and seeing an increased voltage across the start battery, and so charging the house battery.
So far so good, but what happens when the engine is off and the mains charger is on which has a charge output to the start battery and also the house battery.
Does the B2B charger see the increase of voltage across the start battery again, thinks the engine is supplying this and turns on therefore both the mains and the B2B attempt to charge the house battery?
Hope this makes sence?
Thanks

 

[PaulRainbow]

The B2B will, of course, sense the terminal voltage at the start battery and would charge the domestic bank when the shore charger is on. It's possible that the B2|B will also sense the mains charger and think the domestic bank is charged, and go into float, or perhaps the mains charger will sense the charge from the B2B and go into float. I'd consider disconnecting the mains charger from the domestic bank.

 

[Travelling Westerly]

Cheers Paul