diy solar

diy solar

Looking At Charge Controllers...

JeepHammer

Solar Wizard
Joined
Nov 15, 2019
Messages
1,149
Looking for something that's dead nuts reliable and necessary combined with inveter.
I prefer modular, separated CC and Inverter.
Has to be a 240Vac inverter if it's combined, I run a 240Vac system in my home.

Attempting to keep panel strings under 15 Amps, but 8x combined strings are still over 120 and might exceed 150A.
Voltage will be fairly high, say up to 150Vdc,

This will be LFP batteries, so it will have to have programmable upper and lower charge voltage for those batteries.

This is higher voltage than I've run before, so I don't have the CC yet, so recommendations from someone up and running, something that has a track record please let me know what you are running.
The good, the bad, the ugly, problems with installs, customer support, ect, I want to hear it...
 
Schneider MPPT 60-150. Rock solid, programmable. Interfaces with all Conext equipment - via Xanbus or Modbus if you prefer. Aux bus fires relays or whatever. Temperature sensor included. I have three running on two separate systems - never a lick of trouble from any one of them. Worst thing I can say about them is wiring connection box is a bit tight for big fingers - and they aren't cheap. But it's not somewhere I want to cut corners. Documentation is comprehensive. Support is big company style - slow but slow - but there is always someone there. Happy hunting...
 
I too prefer a component system and for mine, I chose a low frequency inverter because of their durability and ability to handle a surge load better than a high frequency inverter. I purchased the 3000-watt DC12v/AC120v version of the inverter linked below. It has no bells and whistles, it's only'meat & potatoes' - built like a tank and user serviceable if ever a repair is ever needed. The inverter has no remote switch and no meter but I'll be adding those things to it. I can't say whether or not the inverter works or how well - it'll be months before I'm able to install it. At any rate, here's a link to a stand alone inverter - DC 24v in w/AC 110v & 220v out:

 
My suggestion JH, look at Victron and their offerings. IF I was building my system today, it would be Victron and absolutely never a combined "all in one" deal from anyone, regardless of brand / label.

Don't know how much LFP you want to have & charge but KISS math says 20A per 100AH of LFP for charging rate for a polite 0.2C charge rate.
 
Midnite classic 200 or 250 is hard to beat for programable and rock solid. You would need two.

Not sure of your coldest temps. Leave headroom for high voc if you need it.

Whiz bang battery monitor and classic local app dashboard is great. Never had an issue with dozens and dozens of them. Many have been out there for 7-8 years and no service calls yet!
 
Because I am already using a Classic-200 I will have to get another Classic for the new panels I plan to install in the spring. At least with the Classics, I can daisy chain them together & use follow-me feature to manage both controllers from one control panel and simplifies my software that I am creating. Already have a Modbus app written to interact with the Classics.
 
Because I am already using a Classic-200 I will have to get another Classic for the new panels I plan to install in the spring. At least with the Classics, I can daisy chain them together & use follow-me feature to manage both controllers from one control panel and simplifies my software that I am creating. Already have a Modbus app written to interact with the Classics.

Steve, what is your Coulomb rate?
You points out .2, 20% of battery capacity in a previous post, and I've seen others say not to exceed .5, 50% charge rate, I'm wondering what the 'Best' limit is?
 
Steve, what is your Coulomb rate?
You points out .2, 20% of battery capacity in a previous post, and I've seen others say not to exceed .5, 50% charge rate, I'm wondering what the 'Best' limit is?
TBH I am not sure what your asking. My C-200 SCC can output a max of 79A. With 935AH (22Kwh+) of LFP in 3 packs, 79A falls a tad short.
 
What is the maximum 'C' charge rate you would consider 'Safe' for Longevity?
You suggested .2 (20%) of battery capacity earlier, I've seen .5 suggested as an upper limit...
I'm all about longevity, but 20% seems a little too conservitive (lazy) in my situation being off grid...
I've got panels coming that *Could* easily do much more, but I intend on using charge controllers (redundancy) to regulate what the battery strings get for maximum charge rate...

I've got a Chargery 16T coming, but they are saying it could be late March before it shows up...
 
What is the maximum 'C' charge rate you would consider 'Safe' for Longevity?
Ultimately, it depends on the cells / packs you are charging. Different manufacturers have different specs and even the cell types can vary a lot. Some high discharge cells can also accept a high charge, more common cells will only take 1C max. I've seen some cells advertised to perform for 3C, some even 6C …. I would never dream of doing that nor would I have use for such "expensive" cells as they cost a heck of a lot more too. I was flabbergasted when I saw the price diffs for high capacity cells. Really, you need the cell specs in those packs you got, so you know what the cells want, what they will put out & take in for charging. You know you will be 100% safe at .2C your pretty safe (I'd say 90%) at .5C @ 1C if the cells accept it, your good BUT you'll have to eagle eye the amps so when your full you stop and that should be OK too... now YOU know what your doing, a noobie could be treading into nasty places anywhere beyond .5C simply because, not all cells are equal.

Re "Chargery" they go back to the facility on the 10th and will start shipping from there on. If you bought from resellers on Ali*, Amazon or Ebay I have no clue. I buy direct from Chargery and that is the info Jason gave me during our exchanges yesterday & today. Everything is quite bungled up over there and the drama-llamas are having a field day making it worse...
 
Ultimately, it depends on the cells / packs you are charging. Different manufacturers have different specs and even the cell types can vary a lot. Some high discharge cells can also accept a high charge, more common cells will only take 1C max. I've seen some cells advertised to perform for 3C, some even 6C …. I would never dream of doing that nor would I have use for such "expensive" cells as they cost a heck of a lot more too. I was flabbergasted when I saw the price diffs for high capacity cells. Really, you need the cell specs in those packs you got, so you know what the cells want, what they will put out & take in for charging. You know you will be 100% safe at .2C your pretty safe (I'd say 90%) at .5C @ 1C if the cells accept it, your good BUT you'll have to eagle eye the amps so when your full you stop and that should be OK too... now YOU know what your doing, a noobie could be treading into nasty places anywhere beyond .5C simply because, not all cells are equal.

Re "Chargery" they go back to the facility on the 10th and will start shipping from there on. If you bought from resellers on Ali*, Amazon or Ebay I have no clue. I buy direct from Chargery and that is the info Jason gave me during our exchanges yesterday & today. Everything is quite bungled up over there and the drama-llamas are having a field day making it worse...

'Drama Llamas' is right! :(

What I've settled on is 200Ah emergency maximum from 220Ah cells, still really safe the way these cells tested out.
I'll keep an eye on them and change as they age...

A couple of the lead/acid battery blasters I have will be what I think will be reasonable at between .25 & .3 'C' per string, I'll start with that, watch temp rises and adjust from there.
I'm staring with 3ea 220Ah/48V strings, and I *Think* I can add 6ea if the supply of those surplus rack cells holds out that long.

I moved 3 big steel case batteries out, and two huge steel case batteries out over the weekend, and I'm paying for it, they have to go through the house now and even on rollers it's REAL WORK and my back is killing me...
I can get all the way to the back wall in the utilities room (40' shipping container) for the first time in years without crawling over crap, and I like that part!
I really didn't realize how 'Mad Max' everything was cobbled together, so the 20 year update/rebuild is about 15 years overdue...

My wife isn't happy about the steel cases on the patio, but I have to wait until the ground firms up to get anything big enough to lift/carry them off...
At least I'll have a fork lift for that, not pry bar & blocks to get them up & down!
What a PITA!
Two more to go and I get to reclaim the original workbench from 20+ years ago, then the LFP install can start.

My trash looks like Amazon/eBay/AliExpress threw up in it! ;)
4-8 WAY over packaged things show up every day... Dribbling in slow but steady...
No 'Express Shipping' when I'm not passing the cost onto a customer.

Thanks for all the help, and let me know if I can return the favor.
 
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