DC-DC Charging ?
When you add a DC-DC charger from the truck as in several threads about that, does that put the house batts in parallel with the engine batt? (as with normal "alternator charging" via 7-pin) Or is...
Forum Discussion
Is everyone getting one of these things? :)
It says to put the unit as close to the house batteries as possible. Makes it tricky for using with a trailer or truck camper and have fat wiring to the truck.
Not clear to me, but they want to reduce voltage drop between unit and starter batt, but want the unit closer to the house batts. So longer wires will be from unit to starter batt, but they will need to carry the higher input amps. Maybe putting the unit closer to the starter batt makes more sense? Guess it depends on your set-up and what your voltmeter tells you once you try it out.
I was looking at making it portable with quick connects of some sort, but I don't need it in the Class C.
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EDIT--engine bay gets really hot! I tried an inverter above the battery with the hood open when idling, and it got too hot and shut down. Had to hang the inverter out over the fender away from the heat.
They say to install it where it gets some cooling air flow, more like with a solar controller. Don't know if the engine bay gets cool enough when driving down the road compared with parked and idling with hood up.
All this wiring in truck or MH seems to be about getting the wires past the firewall. That is a PITA when I looked at doing that before.
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Did you read the manual near the end on how to set it up for LFPs? Do you agree with their approach?
The main worry seems to be how the input will draw steady high amps from the alternator, which might not be up to that for a long drive. No worries with the 20 amper pulling 30 amps, but choosing a higher amp version of the DC-DC has to match what your alternator can handle.
But then choosing a lower amp unit might be useless for not enough charging amps to the house batts to make it all worthwhile--as in my Class C.
It says to put the unit as close to the house batteries as possible. Makes it tricky for using with a trailer or truck camper and have fat wiring to the truck.
Not clear to me, but they want to reduce voltage drop between unit and starter batt, but want the unit closer to the house batts. So longer wires will be from unit to starter batt, but they will need to carry the higher input amps. Maybe putting the unit closer to the starter batt makes more sense? Guess it depends on your set-up and what your voltmeter tells you once you try it out.
I was looking at making it portable with quick connects of some sort, but I don't need it in the Class C.
---------
EDIT--engine bay gets really hot! I tried an inverter above the battery with the hood open when idling, and it got too hot and shut down. Had to hang the inverter out over the fender away from the heat.
They say to install it where it gets some cooling air flow, more like with a solar controller. Don't know if the engine bay gets cool enough when driving down the road compared with parked and idling with hood up.
All this wiring in truck or MH seems to be about getting the wires past the firewall. That is a PITA when I looked at doing that before.
--------
Did you read the manual near the end on how to set it up for LFPs? Do you agree with their approach?
The main worry seems to be how the input will draw steady high amps from the alternator, which might not be up to that for a long drive. No worries with the 20 amper pulling 30 amps, but choosing a higher amp version of the DC-DC has to match what your alternator can handle.
But then choosing a lower amp unit might be useless for not enough charging amps to the house batts to make it all worthwhile--as in my Class C.
