LFP Battery Bank runs the air conditioner!

**rickst29** · 06-24-2022, 11:05 AM

Yesterday, I added the new 230Ah battery pack to the previous and smaller ones (totaling about 225ah), and wired up the "new" Inverter. I'm still waiting for delivery of a good soft-start device (a learning device, replacing the AC unit's "start" capacitor and also optimizing use of the "run" capacitor). But I couldn't resist trying it, just once for a couple of hours.

This was the original OEM AC unit form 2006. It ran great, although I turned it off after a couple of hours on "maximum cool" with the temp dial turned to maximum cold. The batteries still had plenty gas left, although my maximum run time is probably only about 3.5 hours (leaving lots of battery power in reserve for "other things".
- - -
With these final upgrades done, the "ultimate 2619" will be pretty much finished. No Mo' Money!

**rich2468** · 06-24-2022, 03:21 PM

Quote:

Originally Posted by rickst29

Yesterday, I added the new 230Ah battery pack to the previous and smaller ones (totaling about 225ah), and wired up the "new" Inverter. I'm still waiting for delivery of a good soft-start device (a learning device, replacing the AC unit's "start" capacitor and also optimizing use of the "run" capacitor). But I couldn't resist trying it, just once for a couple of hours.

This was the original OEM AC unit form 2006. It ran great, although I turned it off after a couple of hours on "maximum cool" with the temp dial turned to maximum cold. The batteries still had plenty gas left, although my maximum run time is probably only about 3.5 hours (leaving lots of battery power in reserve for "other things".

- - -

With these final upgrades done, the "ultimate 2619" will be pretty much finished. No Mo' Money!

Congrats Rick!
For curiosity can you share how many watts you experienced your Air Conditioning pulling?

**rickst29** · 06-24-2022, 08:16 PM

Quote:

Originally Posted by rich2468

Congrats Rick!
For curiosity can you share how many watts you experienced your Air Conditioning pulling?

It averaged only about 1600 watts AC, closer to 1900 VA on the DC side. It was a relatively cool day, low 80s.

**jagizzi** · 06-25-2022, 07:42 AM

Wow, you must have some beefy cables around that inverter to pull that kind of power ;-) Nice job Rick!

**rickst29** · 06-25-2022, 09:34 AM

Quote:

Originally Posted by jagizzi

Wow, you must have some beefy cables around that inverter to pull that kind of power ;-) Nice job Rick!

dual AWG 2/0 cables, one pair for the +12v input post and the other pair for the 12v grounding-return input post. AWG 4/0 would have a theoretical advantage if cable distances were longer, but they all super-short.

makriegz · 05-22-2023, 10:05 PM

Hey there. I've just bought a 2007 3124KS with the WFCO power center. I also bought a 300Ah Smart LiFePo4 battery.

I'm gathering that I need to upgrade my converter, so that it will charge lithium nicely.

And also, that I'll need an inverter, separate from the power center. Have you wired your batteries with 1 cord leading to the converter, and another cord leading to your inverter? And then, you plug your shore power cord into your own inverter?

Hmm... that made sense before I typed it, but now I'm seeing... then it would try to use my battery to power everything, including charging my battery.

I must be missing something about how to get the battery to power the 120VAC side.

Wavery · 05-23-2023, 07:24 AM

Quote:

Originally Posted by makriegz

Hey there. I've just bought a 2007 3124KS with the WFCO power center. I also bought a 300Ah Smart LiFePo4 battery.

I'm gathering that I need to upgrade my converter, so that it will charge lithium nicely.

And also, that I'll need an inverter, separate from the power center. Have you wired your batteries with 1 cord leading to the converter, and another cord leading to your inverter? And then, you plug your shore power cord into your own inverter?

Hmm... that made sense before I typed it, but now I'm seeing... then it would try to use my battery to power everything, including charging my battery.

I must be missing something about how to get the battery to power the 120VAC side.

Do google search for "Will Prowse ATS".

**rickst29** · 05-23-2023, 09:44 AM

This one is the best choice for a "30 Amp" trailmanor:
https://www.bestconverter.com/PD-510...010Q_p_28.html

It contains two switches, one for the alternative "hot" wires and the other for the corresponding current carrying "neutral" wires. The output goes to the WFCO 30A AC circuit breaker.

There are two input wire sets. In normal (off) position, the transfer switch should connect the TM "30A" 120v power cord wires (from the grid, or from a campground power pole).

When power becomes present on alternate leads (your Inverter), the switches change position at the same time- first disconnecting from "the grid", and then connecting your Inverter (with a momentary disconnected state in between those two connected states)

This does not assure that the Inverter gets turned off, but it DOES assure that the grid connections will never be active at the same time.
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You will also need separate switch (or dedicated circuit breaker) to prevent the power converter from trying to charge the batteries from Inverter power, in an inefficient "loop" from energy being created by the Inverter.

**Shane826** · 05-23-2023, 10:08 AM

I like some of the other transfer switches where the inverter will run unless it sees 120VAC input (shore power, generator) from the plug. Again, you’d have to turn off the inverter manually when not using it but I’d rather have it be shore power dominant. That way if you’re plugged in and you lose power the inverter is on stand by.