PD or Iota for my upgrade?

BFL13 wrote:
The Trimetric can be programmed not to reset the AH automatically when charging stops.

Yes, I've been through the manual. By default in the L1 mode it resets when the voltage is above the voltage limit (typically set to 14.3 for a 14.4 volt charger) and amps fall below the amp limit (typically set to a few percent of the 20 hour capacity rating).

The numbers it uses to compare to the settings are supposed to be pretty long term (5 minute) averages.

I'm not totally sure why it reset on me. It did it right after the inverter did a safety shutdown. This was the first time I'd tested it out, so I'll watch it in the future.

ISTR the PD was rated for its watts at 13.6 so when you go to 14.4 it makes the amps less for the same watts.

It is rated for full amps at 13.6, but there's nothing I can find that says it will reduce amps at the higher 14.4 voltage. I've looked over the circuit, and can't find anything that indicates it would do that. I know it will do 80+ amps at 14 volts, as I've seen it do it several times now. I'm not sure what happens at 14.4 volts.

You want a converter to do its full amps at the higher voltage.

I want it to supply 80 amps at 14.4 volts, but I'm not completely sure how much it matters over the last few tenths of a volt. The battery bank should be approaching fully charged at that point. Unless the bank is huge, I'm not sure if it will take that much current.

On a related matter - Some questions were asked about the 80 amps I measured at 14 volts in a short test I did earlier when the battery was guesstimated at around 94% SOC. I got that estimate from recalling about 12 AH used when the inverter and Trimetric reset and about another 15 AH used later - all on a 460AH battery bank.

Last night I was testing a smaller load on the same inverter (DW replaced the hot pot with a lower wattage unit) and I ran a 95 AMP load for 6 minutes on a fully charged 460AH bank. That's under 10AH or about 98% SOC. When I turned on the PD I saw over 70 amps for a while.

I suspect it's supplying a surface charge and doing its chemical magic in the fluid close to the surface of the plates during that short initial, high amperage charging interval. The battery is probably acting a bit like a smaller battery as the battery acid hasn't had a chance to diffuse and equalize around the plates. As time goes on, I expect it to would reach steady state with a more limited current.