Redid wiring, a couple of weird things.

[Laskadog]

Hi all,

I just redid the wiring around my batteries. I have 2x 12v AGM batteries paralleled as a house bank and 1x AGM start battery. In addition to upsizing the wiring and installing bus bars, I installed an ACR and Dual circuit switch. Everything worked great until I checked my Victron battery monitor. With the switch off, there was a -0.15A drain. I believe that the old analog battery monitor was to blame. Before the rebuild, banks 1 and 2 were reversed, so when I installed the new battery switch, I reversed 1 and 2 at the battery switch so they were correct on the gauge. The drain went away when I reversed them back to the way they were before. For the life of me I can't understand why this did the trick.

Weird thing #2 is that when I turn the battery switch to off, the light stay on for a second them dim until they are off. That's new! What's that all about?

Any insights would be greatly appreciated.

[Laskadog]

I forgot to mention the most important part. When I unplugged the house bank, the lights stayed on. So some current was getting from the start battery to the panel.

[HippieTye]

do you have a battery combiner or isolator?

[Laskadog]

Originally Posted by HippieTye

do you have a battery combiner or isolator?

I have a Blue Sea ACR. I could check if it staying open. Hadn’t thought of that on the spot. It did combine properly when the charger was turned on.

[SailingHarmonie]

Originally Posted by Laskadog

I forgot to mention the most important part. When I unplugged the house bank, the lights stayed on. So some current was getting from the start battery to the panel.

Or maybe from a solar panel?

Can you post your wiring diagram? Without it there is a lot of guessing...

[Laskadog]

I'm on the hard right now, so although the wiring is run to the + and - bus bars, the panels are not plugged in.

Unfortunately my original hand drawn wiring diagram is so scribbled and modified that it wouldn't be any good to anyone but me.

The fact that the lights stayed on when I unplugged the house bank lead me to think that the 2 banks were inadvertently paralleled somewhere. The only place I could see this happening was the Voltage gauge, which is why I unplugged it, thus resolving the problem.

I'm going to try to revert back to when the problem occurred to see if it repeats itself. Perhaps it was a fluke, like 2 wires touching in the back of the switch or a defective ACR or switch. I'll do more troubleshooting and report back.

I guess my question was more specifically, can these old analog voltage monitors be capable of accidentally paralleling the batteries they are monitoring? Thanks.

[NorthCoastJoe]

If there is a charging voltage on either bank the ACR will join the batteries.
The ACR is always on and draws some current 24/7.

When our solar is putting out our ACR joins our batteries. It's a simple device that responds to voltage.