Chasing milliamps

[Bill Lampkin]

So I've been looking into why my house battery bank voltage drops after charging, even though I had the batt disconnect open or off . The only thing that bypasses the disconnect switch is the inverter. By using my mini DC clamp meter, I found that the inverter was drawing about 2-3A at idle, so I turned off the inverter switch. Current went down to 1.5A, so I start checking to see if the disconnect switch was  really off. I found voltage on the house side (at the rear run bay) at 11.5v, so I replaced the disconnect switch with a new Blue Sea 300A switch. Now I have 0 volts on the house side with the disconnect open, but I'm still reading about 250mA of DC (1/4A). I thought the old Heliotrope solar controller might have some idle current, as the coach is stored under an awning so the panel sees no sun. I disconnected the wire from the controller to the battery buss and still read the same 250mA of current. If I had the coach up in the air, I could clean the grounds......

[Steve Huber Co-Admin]

Bill,
Check the connections from the batteries to the fuse and then to the inverter. You may have leakage to gnd at one of those connections.
Steve

[Bill Lampkin]

Thanks Steve, The box with the fuse in it looks like it just came out of the factory-each connection carefully coated with insulating shellac, clean as a whistle. I haven't checked the big cables where they attach to the inverter, but it too is inside a compartment (mounted on the celeing) and is also clean. I can't get the rig up in the air to check frame grounds, I'll have to wait for an annual service to get that done. Maybe I'm chasing my tail trying to chase down a 1/4A leak.....

[Steve Huber Co-Admin]

Bill,
You might also want to ensure your batteries are clean. You can get parasitic leakage along the battery outer surface if there is contamination present.
Steve

[Kevin Higgins]

Hello, not sure if it’s OK to add something to an old form. If not please let me know. I’ve been going through the same issue with my coach and I just got off the phone with magnum and technical support told me the inverter will still draw .4 A In the off position.