PD or Iota for my upgrade?

DryCamper11 wrote:
When I'm back from vacation, perhaps I'll have a chance to understand the circuit a bit better.

I'm back :)

Here's brief report on the system used for almost 3 weeks of dry camping - generator only charging - no shore power, no solar.

Both the DW and I were very happy with the new system - 460AH of four 6 volt Sam's Club/ Deka East Penn monitored by the TriMetric and charged with the modified PD9280.

Although I'd seen this at home, I was slightly surprised that the manual charge mode override on the PD9280 worked even when not charging. You could tell it to switch to my modified 14.8 boost mode even when it had no power to do any charging.

We only needed to charge every 3 days or so, and I seldom went much below 80% - never below 75%. We're not heavy users of power. I'm probably a bit larger in battery capacity than necessary. The morning coffee boiling of 96 amps for 5-6 minutes and occasional heating of leftovers in the microwave were the big users of power.

I had installed a switch to revert from my modified boost of 14.8V back to the unmodified boost of 14.4V, and I noticed the following:

If I charged to 14.4V, the current would taper slowly in the typical decay pattern. However, if I threw my mod switch, to 14.8V boost, charge current would immediately jump up and start a new decay. I did bring my specific gravity tester and I could clearly get more total charge into the bank and get it in faster with the modded higher voltage. I saw very little excess gassing from the batteries. IOW, it appeared I could get to the same SG and charge level of the 14.4V factory setting much faster with the 14.8V setting.

I took along my Vectra 40A charger and tried to run it in parallel with the PD9280 on the gen, but it would turn off and say "FULL" long before the modded PD9280 would stop charging. I suspect that 14.4 is just too low for my dry camping usage, so I'm pleased with the mods.

It was nice to be able to run high power appliances, like the toaster and coffee water boiler early in the morning without the gen - I always felt I should wait to run the gen until as late as possible.

I found myself looking for excuses to run the gen. Taking a shower and running the electric HW heater in combo with the gas heater was one. I took along my SawzAll for firewood cutting, and running the gen to power that was another useful excuse. My MSW inverter is only 1200W and the SawzAll uses about 1600W.

The greatly reduced gen run times cut my typical fuel usage significantly. The Onan is not known for fuel efficiency, so packing the recharge into a few short sessions made a noticeable difference in fuel consumption. It hasn't paid for all the new toys, but at gasoline $4/gallon it's making a dent in the cost.

Excitement: a loose connection on the inverter produces a lot of heat at 100A :) A lot of heat produces a distinct smell as the plastic insulation melts.