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Yoshi_TAB said: Most people only see 85-90% charge with a 8735P.  For some reason mine will get to 100%, but very slow.

AnOldUR said: I had thought that was strange until recently. When I plugged into shore power my LiFePO4's went to 87% overnight and I thought that was it. Over the next few weeks I notice it's slowly gone up to 99%. I'll still have to use my NOCO to top off when time is important, but it's nice to know it won't always be necessary.

Here's a possible explanation for what you're experiencing.

WFCO converters have a bad habit of only operating in 13.6v absorption mode (vs 14.4 - 14.6v bulk mode), which increases charge times considerably.  13.6v will eventually charge a lifepo4 battery to ~100% SOC assuming the 12v loads on the WFCO converter are minimal. Any additional loads will reduce available charge current, further increasing charge times, and in some cases prevent the lifepo4 battery from ever achieving a 100% charge.

Another contributing factor is the voltage drop due to undersized wiring used in many RV's--including NuCamp.  Although the WFCO converter may produce 13.6v at its output, voltage drop due to undersized wiring can reduce the voltage at the battery terminals to less than 13.6v, preventing a lifepo4 from obtaining a 100% charge.  This voltage drop is why some folks only achieve a 85 - 90% SOC.  A lifepo4 battery needs at least ~13.6v to charge to 100% (there's some debate as to the specific voltage necessary to achieve 100%).

I believe most folks would be very surprised to see how much faster the batteries in their 320's would charge with a 35a converter that does go into 14.4v (or 14.6v) bulk mode properly.  When charging a 12v lifepo4 battery from 0 to 99% charge times are typically twice as fast at 14.4 - 14.6v vs. 13.6v.  Depending on the size of the battery bank (and other external loads) it can sometimes take a lifepo4 battery hours to charge from 99 to 100% at 13.6v.  At 14.4v - 14.6v, it may only take a matter of minutes.

Thanks to @bjn2 for confirming that the pin on the Fastway breakaway cable will work in the Esco switch. Thanks also to the other responders for opening my eyes on the subject of breakaway cable length; I had no idea it was a controversial issue!

On the subject of cable length, some may recall that I posted a while back in another thread about experiencing an unanticipated separation of my T@B from my TV. That incident did not result in the breakaway cable pulling out and engaging the trailer brakes, something that until now, I hadn't thought about. Let me also add that my safety chains are shortened, and are just long enough to not be fully stretched when turning/backing. 

As near as I can tell, the breakaway cable as supplied by nuCamp was 48" which leads me to conclude three things.

The first is that the four-foot breakaway OEM cable is sufficiently long, at least for a 320 BD (2021). The second is that since the electric brakes were not triggered during the disconnect incident, it would seem that nuCamp believes that the braking system should be engaged only when the trailer becomes fully disconnected from the TV. Third, if statement #2 is correct, you can safely use either the 4' or the 6' Fastway cable, since it a coiled design. You would not want a six foot cable if you used wire rope because there would be too much excess.