Lance TC - lithium - DC-DC charger question
I’ve just purchased a 2020 Lance 975 that will sit in my 2022 F350. I have to install the Lance 6-pin at the front of my bed. I will also replace the two 12V lead acid house batteries with one 200 a...
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Another factor is to keep the input voltage high enough so the DC-DC buck/boost converter can maintain the set output amps and voltage to the camper battery. This is a separate issue from fusing the input side for its wire size, and having the input wire gauge match the input amps.
To achieve that you have to oversize the input gauge wiring beyond what is required to carry the input amps safely. Eg to maintain 14.7v and constant rated output amps to the camper batt, you want say 13v input, despite the DC-DC boost spec that it says it can do it with input as low as maybe 10v. Not mine anyway! Needs higher input voltage.
One way that worked for my set-up is to run the positive cable as say your 6 AWG, but use the truck frame for the neg input path. it is the total R on the circuit that matters, so going fatter on the neg only helps quite a bit to lower total R.
Some folks run fatter wire for both pos and neg but I have no easy route from the truck engine batt back to the truck bed to go to the camper. However it is easy to connect the neg DC-DC input wire to the truck bed as a short wire run.
I use the 7-pin (6-pin) 12v wire which is way too thin for the pos input to the camper where the DC -DC is, because it already has its route through the truck, but make up for that being too thin with the truck frame being the neg path which is like really fat wire.
I ran some tests and at first using both pos and neg 7-pin wires the DC-DC could not hold its output spec because the input voltage drop was too great. Swapping to the truck frame for the neg input path solved that, just barely, but it does the job now.
Oversizing the input gauge like that also means the Dc-DCdoes not need to pull as many amps from the truck battery and so the alternator.
I do not have an isolator in the Chev, like a Ford has. To turn on the Renogy DC-DC I ran the little B+ wire around to the input pos side with a simple on off switch in that wire. All in the camper. So I turn it on and off manually as needed
To achieve that you have to oversize the input gauge wiring beyond what is required to carry the input amps safely. Eg to maintain 14.7v and constant rated output amps to the camper batt, you want say 13v input, despite the DC-DC boost spec that it says it can do it with input as low as maybe 10v. Not mine anyway! Needs higher input voltage.
One way that worked for my set-up is to run the positive cable as say your 6 AWG, but use the truck frame for the neg input path. it is the total R on the circuit that matters, so going fatter on the neg only helps quite a bit to lower total R.
Some folks run fatter wire for both pos and neg but I have no easy route from the truck engine batt back to the truck bed to go to the camper. However it is easy to connect the neg DC-DC input wire to the truck bed as a short wire run.
I use the 7-pin (6-pin) 12v wire which is way too thin for the pos input to the camper where the DC -DC is, because it already has its route through the truck, but make up for that being too thin with the truck frame being the neg path which is like really fat wire.
I ran some tests and at first using both pos and neg 7-pin wires the DC-DC could not hold its output spec because the input voltage drop was too great. Swapping to the truck frame for the neg input path solved that, just barely, but it does the job now.
Oversizing the input gauge like that also means the Dc-DCdoes not need to pull as many amps from the truck battery and so the alternator.
I do not have an isolator in the Chev, like a Ford has. To turn on the Renogy DC-DC I ran the little B+ wire around to the input pos side with a simple on off switch in that wire. All in the camper. So I turn it on and off manually as needed
