The other mark can comment on this better than I ever can, but...

Yup, but that disconnect voltage, well on my old blue sea acr, is adjustable. I think I have mine at 12.65. The sense wire to the starting battery.

And it hasnt been an issue for me in the 17-18 years I’ve been using the ACR.

Alistair 

> On Apr 28, 2020, at 7:41 AM, Mark McCulley <markmcculley@gmail.com> wrote:
> 
> I have a Blue Sea m-ACR installed in my van, there is one aspect of how it
> works that I'm not sure that I like. It does not isolate the house battery
> from the starting battery unless the voltage on one of the batteries goes
> below 12.75v. When I installed the ACR I thought that the batteries would
> be isolated whenever they weren't being charged but this is not the case.
> 
> Regards,
> Mark