LiFePo4 "upgrade" in progess.

[Casey Freswick]

Just ordered my new converter: PD 4655VL 55 Amp Converter Upgrade, Optional Remote Pendant

Thanks again fro all the help rickst29

[rickst29]

Next upgrade: Your battery is capable of running nearly all kitchen appliances through a big inverter, without firing up the generator. (Although that's obviously for a limited amount of time.)

My own inverter is supposedly pure sine wave (but I haven't borrowed a scope to check on that) It has great reviews on Ebay. 1500w continuous, Up to 3000w for a short "motor start" burst. Not for making coffee on 120v, but certainly good for running the coffee grinder - and even the microwave, for a quick warm-up. https://www.ebay.com/itm/EDECOA-Powe...V/232635461270 This must be connected from your battery using wire size #2 or larger (unless it's extremely short, #1 AWG would be better.) Add a correspondingly huge circuit breaker. (I've got a 200A breaker on that lead, and the wires are AWG-2).

If you buy the same Inverter - be sure to THROW AWAY the supplied cables, the wire size is far to small. From the outside they look fat enough, but it's mostly insulation. You'll need to solder your own ring connectors on your wires (again, #2 or larger). Because the TM has vibration going down the road, maybe use high-silver solder, it's less prone to cracking.

[tentcamper]

I have the PD Charge Pendant in our MH. Very nice for a faster charge when we fire up the 6.5K onboard propane Generator. But with the solar and batteries it does not get used but maybe 1 out of 15 nights out.

[Casey Freswick]

I want to thank RICKS29 for all his help, even behind in private messaging. I sill need to fire up, that may not be the best term to use, my new converter. But I keep adding new projects. With a bigger battery I thought I should have a designated outlet for my inverter and ran a wire through the space behind the converter behind the toilet, (upgraded Sealand), under the sink over the refrigerator and using the phone space for a new outlet. Now will not need to have cords hanging all over the place. Second, put in a external when TM is down outlet for shore hook-up. Put on a new 30 male end in the box that I can plug a 30 amp extension cord into. I now have 3 of them. Put in an outside box next to the bumper, Took out the “wall” in the storage compartment that separated the 30 amp cord. Will us a cheap electrical wind up holder for my extension cord which unwinds and winds up way easier than pushing and pulling a 30 amp cord, especially in the cold.

[rickst29]

There are automatic "Transfer Switches" which can switch 120v power sources, based on which one is hot. Since your converter is in the rear, fairly close to the Power Center and the 30A TM shore power input cord, you could have used one of these: https://www.amazon.com/Technology-Re...dp/B00IYUPRUG/
There are two input cords (The TM 30A, and the the Inverter). The Inverter dominates, but there is a 20-40 second delay before Inverter Power is selected. output goes into the WFCO "main breaker", the 30A hot cord. These devices have the obvious advantage of power ALL 120V outlets in the TM, rather than just one

[Bill]

I'm not sure why the switch would be "generator dominant" as the manufacturer says, or "inverter dominant", as you suggested. Could you reverse the connections to make it "shore power dominant"?

Bill

[rickst29]

Originally Posted by Bill

I'm not sure why the switch would be "generator dominant" as the manufacturer says, or "inverter dominant", as you suggested. Could you reverse the connections to make it "shore power dominant"?
Bill

You could definitely switch the input connectors, because it has to be able to draw it's own operating power from either input connection. The delay timings would also switch. I think that the standard scheme is to favor the generator/inverter, because you would not normally have that source device active unless you think that you need it.

[rickst29]

Originally Posted by rickst29

The BMS 'over volt disconnect' charging limit is 14.6V, a low figure which is becoming more prevalent in new Chinese LiFePO4 batteries. It makes charging a bit more gentle.

But IIRC, the Progressive Dynamics Lithium chargers (including my 'Wildkat') will run "Constant Voltage" at 14.7, which is too much for completing the battery charge at 100% of capacity. These batteries will pull the entire output of a Converter until they are nearly done, so a "Constant Current" limit occurs first (at a slightly lower Voltage)....

Using my new external "12V port connector" setup, I checked Voltage on that first LFP battery for a few days. The PD Converter did not try to keep it "too high" all the time, and worked as single-stage charger: Constant-Current, with voltage allowed to rise (probably to 14.6, when the BMS seems to have cut off charging current). Upon detecting zero charging current, it stopped charging. The PD does not attempt to recharge until the battery is much lower.

[rickst29]

I ran the battery against a pair of resistors in parallel, using auto "jumper cables" to make the connections. Current varied with battery voltage (under load), from a bit above 6A down to about 5.7A at the end of testing.

After disconnecting the load circuit, I allowed a few minutes of time for battery voltage to recover to steady state. With just two meters connecting a very small discharge current, ending no-load Voltage was 12.18V. From LiFePO4 discharge voltage tables, that corresponds to about 11-12% SOC.

From 100% full charge (14.6V at test circuit connection time), the "pretty good" Coulomb Counter measured 53.3 Ah consumed. 53.3 Ah / 89% battery used yields a total capacity of only 59.9 Ah. I will contact the seller and DHGATE to arrange for partial refund.
- - - -
This was a https://www.dhgate.com/store/product...rod|3232919042

[Bill]

I'm sorry to hear that. I was looking forward to hearing good reportsl and learning more about LiFePO4.

Chinese, of course. I'm not sure what excuse they will use. Probably something about end-of-life voltage being 10.0 volts instead of 12.8 volts.

I noticed that one of the reviews described exactly what you are experiencing.
Buyer beware these are 50ah batteries with a 100ah sticker. I tested all 3 batteries I ordered and the all tested to 51 ah.These are a rip off. .

Good luck, and let us know the outcome.

Bill