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Setting up charge controller for LiFePO4

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Hi guys,

Another beginner here having trouble setting up the charging profile for my batteries. Batteries are in place, panels are set up (on my van). Turns out I have no idea how to set up the profile and research has only been more confusing.

Here's what I am working with:
Charge Controller: EPEver MPPT 40A Tracer
Charge Controller: EPEver MPPT 30A Tracer
Solar Panels: (3) 160 Watt 12V Renogy Mono Panels wired in series
Solar Panels: (2) 160 Watt 12V Renogy Mono Panels wired in series

Batteries: (2) EWT LiFePO4 12V 200Ah Batteries wired in parallel for 400Ah 12V Total.

Some screenshots of my battery specs. Also attached the battery specsheet:
https://lensdump.com/i/0WZjFx
PCM
https://lensdump.com/i/0WZIIH

I'm not real sure which battery specs I need to be looking at and entering into the controller? The EPEver user manual mentions the Sealed(Default) setting in a table. Right next to it is this: Lithium Battery LiFePO4(4s/12V). Is that the right setting? There is a line in my battery spec sheet under the PCM specs saying Battery Link: 4S. No idea what that means though.

Sorry for the ramble, pretty lost here. Any help would be very appreciated. Thanks guys
 

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I would set bulk/boost/absorption (can be called any of those) voltage to 14.4 and float to 13.5. Disable any equalisation, set it to off if you can otherwise set the equalisation time to 0 (check this, 0 can mean infinite for some controllers, in which case set it to 1) and equalisation voltage to 13.5.

The combined current from your panels to the 2 batteries is about 66A max, which means 33A to each battery so that's OK. If one of those battery's BMS disconnects for some reason the other will have access to 66A potentially and that's above the maximum charge rate for your battery. This could be a problem for you but it will be mitigated to some degree by the fact that your solar panels probably won't ever produce their full rated power.

The battery link spec is referring to the number of connections from the BMS to the cells. Since it's a 12V battery you have 4 cells. You can ignore this sort of detail since it's about the internals of the battery that you never see nor access.
 
Thanks very much for the response. Interesting note about potentially having too much charge if one battery's BMS ever went down. Not sure what I would do to prevent that.

I'll give this profile a try and see how things go!
 
Forgot (prompted by another post elsewhere), check the absorption time limit. For the first charge up keep an eye on the charge current and when it has fallen (no load on the battery when doing this) make a note of the time it took from when the unit switched to absorption charging mode and when the current fell far enough and set that +5 mins in the absorption time limit. The standard lead acid absorption time is far too long for a lifepo4 battery.
 
Forgot (prompted by another post elsewhere), check the absorption time limit. For the first charge up keep an eye on the charge current and when it has fallen (no load on the battery when doing this) make a note of the time it took from when the unit switched to absorption charging mode and when the current fell far enough and set that +5 mins in the absorption time limit. The standard lead acid absorption time is far too long for a lifepo4 battery.

Okay. Would you mind telling me how to check for this? Like do I need to sit around and really keep an eye on it to tell when the charge current has fallen? And what do I use to see that the charge current has fallen..just by looking at the battery monitor? Sorry if those are dumb questions
 
You can use the front panel on the controller or if you have the remote panel you can use that to check the battery voltage and current.

The time isn't ultra precise so you don't need to sit around staring at the panel, just checking every 15 mins or so towards the end of the charging process is quite good enough. Once you see the battery is at absorption voltage or higher, or the controller says it is in absorption mode, note the time then when you see current has fallen to say 2 amps, call that the end time and enter that +5 mins as your absorption time limit.
 
Hi guys,

I just wanted to post a follow up to say a big Thank You! to this forum and everyone who responded. With your help, I was able to set up my charge controllers and my panels/controllers/batteries are doing excellent. What a great feeling to be basically finished with the electrical system and to at least have a decent understanding of what it all means.

If any other beginners refer to this thread in the future because you purchased an EPEver Charge Controller, take my advice. Be sure to purchase a separate remote controller. For my range of model, it's the MT50 LCD remote meter. The controller itself only has two buttons on it. I have no idea if its even possible to configure that thing with those two buttons.
 
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