Truck Camper on Chev vs Trimetric Monitor

[BFL13]

New to me, might be good to know for some others-- (Pin 4 always live in a Chev, but not in a Ford with its isolator)

Had a converter in the camper on house batts but no Trimetric (and the converter has no amps display) but I do have a voltage display in the camper. All good.

Doing a mod that requires swapping out the converter and installing a Vector smart charger instead, which has an amps display, plus I installed my Trimetric from the MH over to help with testing the mods before retuning the Tri to the MH.

So charging the battery today had the Vector showing 18 amps and the Tri showing only 13 amps. (rounded off numbers). I tried a couple different wirings no diff. Where is the 5 amp draw?

Dawned on me that the truck is still plugged in with the camper 7-pin (ok, 6 pin, because no brake pin connection). Unplugged the 7-pin and now they showed 18a and 18a like they should.

I want to leave the 7-pin connected all the time, so it turns out that if I want to recharge the camper batts (house batts) as quickly as possible, I have to pull Stud 1 fuse (for pin 4 power) or just unplug the 7-pin. I can just leave it all as is and accept slower charging to the house.

So this has been the case the whole time before with the converter too. I just didn't know about it without these two displays. With just the Trimetric showing amps, you can't see that the amps number is "wrong".

In my case, with the engine and the house batts in parallel via Pin 4, the charger was giving 13 amps to the house and 5 amps to the engine side.

It is similar with the solar of course; you don't know exactly where all the amps are going.

Anyway, I thought that was interesting! I will have to decide how to play that for whatever the scenario is when it comes to battery charging in the camper. (The MH is a Ford, so not an issue there)

[KD4UPL]

I like the Chevy method. I liked that .y solar kept my truck battery topped up. You can relocate your truck negative wire to make the meters read right.

[BFL13]

OTOH you can keep the engine battery maintained in the Chev while maintaining the house and not have to rig up something like you do with a Ford.
I don't mind it either way; just have to remember because it doesn't show

[Gdetrailer]

For the GM, just add a relay that only applies power to the charge line when ignition is ON (engine running).

That IS what Ford has done since the 1990s.

More modern Fords (2017 and newer) have a computerized solid state towing module that controls the charge line.

And yes, GM was being a bunch of cheapos by not including a relay in the charge line..