Revised power panel/converter and wiring question…

[FireFlier]

Hello New Friends,
New to the group and need advice/opinions about electrical improvements. Bear with me, I’ll try to “keep a short story short” while also providing sufficient detail…

We picked up a used 2018 Jayco Jay Flight TT with 245RLS layout. We are the third owners planning to use RV-parks mostly with occasional off-grid excursions.

Here’s what I have for upgrade hopes/plans…
a) Replace existing 35-amp converter/charger/panel with a Progressive Dynamics 60-amp unit to charge new deep-cycle flooded lead-acid batteries properly and faster. This would require…
b) Larger stranded 2-wire runs to reduce voltage loss between the existing unit and hitch-mounted batteries (currently about 20 feet one-way unless I move the unit).

While reading Mike Sokol’s “No-Shock” and Bill and Jan Moeller’s “RV Electrical Systems” books I noticed that Moeller’s discussion of wire-runs beginning on page 66 and Table 4-3, page 69 says to include the COMBINED length of both positive and negative cables when figuring cable size. The 50-amp table at 40 feet total recommends 3/0 cable with 1% loss for charging circuit.

So, if I’m understanding what I’ve read so far, my choices would be to…
1) Install 3/0 charging cables from to the new unit (mid-ship) to batteries up front. Estimate about 25 lbs. for the new cable. However, can I attach that larger cable to the unit which has terminals for only 6-gauge wire? Other web searches seem to suggest it’s possible and OK, but opinions are divided. Or…
2) Swap the combined converter/charger/panel unit for a separate converter/charger to be installed in the front stowage compartment behind the hitch-mounted batteries. Then install new 120v breaker and 12v fuse Panel(s) where the old WFCO unit was. This would entail new wire leading up front to supply the converter/charger and then sufficient-gauge stranded wires from the converter/charger back to where the original unit was to supply a new 12v distribution panel. Weight might be a little less but not much?

So it seems to me the only impediment to using the easier route (option 1) would be making a safe and reliable connection between the large diameter cables and smaller terminals on the new converter/charger/panel at the original mounting location.

Will sincerely appreciate any corrections to my understanding and other suggestions for making this unit suit our purposes. Cost and sanity savers will also be entertained (entertaining?).

Sincere Thanks and Best Regards!

[morleyz]

My opinion, install the largest cable that fits in the terminals. My Eagle is factory fitted with a Progressive 60amp, mid-ship converter and the wires are just stripped and inserted into the screw terminals, so definitely no more than 6ga (frankly, it looks like 8ga to my eyes). Run has to be 20 feet from the converter to the battery on the A-frame. I know the engineers and installers aren't the greatest in the RV world, but I can't see it being a safety issue if the terminals only fit 6ga and they're not using anything larger from the factory. The other solution just seems like it would be difficult to maintain.

Certainly not a cost saver, but adding solar on top of your converter would speed up the charge. If you plan on going "more" off grid in the future, you can expand the solar to fit your needs and maybe not even need to scrap the 35amp converter. Don't know if Jayco started prewired on the roof in 2018 or not, but I just added a Renogy kit and it was simple to get going.

Final thing to keep in mind, the specs on the converter in my unit say the input current could reach 47 amps, meaning you may need to upgrade your shore power connection as well.

[FireFlier]

Thank-you, I'll check into it further.