[swellguy]

How are you guys wiring up your house battery? I'm planning on wiring mine to my starter battery through a 60A relay triggered by the engine run signal. The CCM says that the engine run signal is on when in run or accessory, the latter seems incorrect. Seems like I don't want it on when I'm in accessory.

They have another lead which uses ground as a run signal which I think can pull the relay down, I may try to use that one instead. Any experience with this?

Any downside to using the run signal? I think accessory is wrong, I think I want both batteries isolated when I'm in accessory.

Which one are you guys using? I guess this is only relevant if you're using the alternator to charge, those using solar only need not respond you know who you are, though I may eventually go solar only at some point.

Thanks!

 

[unclebob]

You want to use the ground run signal. It is only active when the engine is actually running. However it is a low amperage ground run signal so you must use a smaller relay to then engage your larger relay.

I used a small relay from the auto parts store that is designed to be used with horn or auxiliary lights. That relay then energizes the line for my 180 amp battery isolator relay.

If you Google "Ford Transit BEMM manual" you'll find the body builders manual that has a list if the various plugs and what each terminal does.

Make sure you are looking at the plug from the correct direction. The mirror image terminal in that plug is a speed sensor. It activates when the engine starts but deactivates when the vehicle speed exceeds a certain level (maybe 5-10 mph).

If you mistakenly connected that terminal you think everything is working fine until you got everything reassembled and start to drive down the road and the signal deactivate your charging systems for the auxiliary batteries. Then you have to disassemble everything to correct the mistake.

There's a thread on the Forum that goes into a lot more detail on this issue simply search for that thread.

 

[skagitstan]

Could maybe think about using a VSR instead. It will use the voltage at the batteries to determine if the systems should link. If both are below charging voltages, they will stay independent.
Means you don't need to wire up a multiple relay buffer system, or access the run signal.

Stan