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paulz
Member
# Posted: 12 Jul 2021 10:46
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Man likes his coffee..

When the SCC shows 14+ volts, which mine rarely does, it's bulk charging? Was there some usage that caused the need for bulk charging?

I programmed my Epever for LFP (has no pre-programmed setting) according to the values Battleborn suggests:

Over Voltage Disconnect 14.7 V

Charging Limit Voltage 14.6 V

Over Voltage Reconnect 14.6 V

Equalize Charging Voltage shut off or 14.4 V

Boost Charging Voltage 14.6 V

Float Charging Voltage 13.6 V

Boost Reconnect 13.3 V

Low Voltage Reconnect 10

Under Voltage Warning Reconnect Voltage 11.5

Under Voltage Warning 11.5

Low Voltage Disconnect 11.0

Discharging Limit Voltage 10.5

Equalize Duration 0 or set as low as possible

Boost Duration 180 minutes

gcrank1
Member
# Posted: 12 Jul 2021 14:15
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Those settings may well come in handy for me as I transition to LFP!
My old (Mirro-Ware?) 30 cup perc is our water heater; 1000w @ 115vac. It runs fine off the Lil' Champ 1600/2000 inv/gen but no way Im going to try to set up for 90ish w off the 12v bat-bank and inverter. And no need to with a one-pull little genny for a short run.
Fwiw, Ive watched the read-out on my scc, when the bat-bank is full and setting on 'charge current to bat', go up from 'x amps' at maintenance to 'whatever more' the device is I turn on. Kinda handy to see what something is actually using off the array.
I have been thinking of trying to use my toaster off the inv. as a load tester for each battery; ever try anything like that?

paulz
Member
# Posted: 12 Jul 2021 14:37
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I have not. Like you, my electrical needs have been small, LEDs, phone chargers, laptops.. I just recently added a small PSW 1500 inverter to power a ceiling fan, and have started to play around with AC things, vacuum cleaner, tool chargers. Again a slippery slope, wife would love a big screen TV.

Here is the link to the Battleborn page with the LFP specs.

https://battlebornbatteries.com/setting-up-the-epever-solar-controller/

paulz
Member
# Posted: 25 Jul 2021 13:28
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Tell me again why I can't jumper and charge my dump truck battery off the cabin's 12v, LFP solar battery bank? Seems to me it wouldn't be any different than any other system draw.

ICC
Member
# Posted: 25 Jul 2021 18:29
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Are the charge requirements and limits betwwen the LFP and lead-acid identical?

An LFP battery has a lower internal resistance than lead-acid. The LFP will probably reach full charge before the lead-acid battery. The CC will still be trying to send the lead-acid battery current that the LFP does not need. The CC cannot just send power to the battery with the lower state of charge. The charge current goes to everything that is connected. Does the LFP have a BMS that can deal with the voltage/current the lead-acid battery still needs?

All the dame caveats that apply to all parallel connected batteries apply, and are complicated by the different chemistries and their different limits.

gcrank1
Member
# Posted: 25 Jul 2021 18:41
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Isnt the simple solution to just plug a typical fla battery charger into the inverter running off the lfp bank?
Yeah, inefficient dc to ac to dc, I get it. But so what, its all running off your 'free' solar anyway.

paulz
Member
# Posted: 25 Jul 2021 18:46
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Sounds complicated, I'll just use a charger off the inverter, as I do with the tool batteries. Thanks.

paulz
Member
# Posted: 4 Aug 2021 16:16
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Renogy... can't say I wasn't warned.

My first CC fried the mosfets. I did exceed the 100v pv voltage by a bit, but it was supposed to shut itself off. Oh well. I replace it with an Epever, been fine since.

I bought another one, why I don't remember, that's been sitting on a shelf. I decided to hook it up, 20 amp, to a couple of 100w, 30v, 6a panels in series, just to charge car batteries. Put a battery with about 12.4 on it one day, showed it was charging it, went back to the city for a couple of days. Got back, CC showed error E01, insufficient battery voltage. Sure enough, down to 11v.

Hmmm, maybe the battery is toast says I. So I put a different battery on, and put the battery on another charger. Got back here today, another E01 error and dead battery. First battery, on the other charger is fully charged.

Somehow this Renogy is draining my batteries. No load of course. I just hope it didn't do too much damage.

Steve_S
Member
# Posted: 4 Aug 2021 16:44
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I'm sorry to hear that Paul. Not sure how to help you troubleshoot that. The EPEver products are very good "value+" gear. I would first suggest putting the batteries on a proper Bech Power supply with CC/CV and run then down to 10% and Max Charge Amp to full at least twice, which often will "kick" them. IF Lead Acid, double check fluid levels 1st! Sorry I forget if you are using only LFP or a Combo of chemistries now, your stuff has evolved a lot.

I guess once I heal up good enough, and finish the "Toolshed" project and its own Solar System, I'll have to post that up here & @ DIY as well for folks. It's Different, using a Midnite Solar KID MPPT SCC and a few other cool goodies. An alternate kind of system. Sadly, I've spent more time in hospital this past 45 days then I have in the past 6 years.

paulz
Member
# Posted: 4 Aug 2021 16:53 - Edited by: paulz
Reply 


Sorry to hear about the hospital time Steve. I've been fortunate to having only spent a few hospital days so far in my life, but enough to know it's not fun.

I should clarify the CC giving me the E01s is another Renogy, not the Epevers I use at both cabin (LFP) and shop (FLA). It's just a spare I had kicking around but was new in the box. I'm just trying to charge the batteries for the trucks and tractors with it, no load. I know the CCs take some power to run but shouldn't kill car batteries. The first one, that I recharged on another charger, I put it in a tractor and it cranked right over so it couldn't be in that bad a shape

gcrank1
Member
# Posted: 4 Aug 2021 21:51
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I expect that discharge took some life out of those bats but no way to quantify that; they will live until they die.
Do those panels have anti-backflow diode?; ie, maybe its not the scc.

paulz
Member
# Posted: 4 Aug 2021 21:58
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I've never seen a diode on any panel, where to look?

gcrank1
Member
# Posted: 4 Aug 2021 23:00
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Read about 'em, never seen one; my impression has been they reside in the 'box' on the back of the panel.
Iirc, one way to tell if you dont have such or it is 'blown' is if a battery goes dead overnight; ie, the juice gets sucked back out if the panels arent pumping it 'in'.
Im sure somebody else can clarify this for us.

paulz
Member
# Posted: 10 Aug 2021 10:36
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Quoting: gcrank1
Im sure somebody else can clarify this for us.


No update from the resident pros.. I looked at the two panels yesterday, couldn't see a way to open the little box.

Seems odd though that the CC would allow the juice to get sucked back out.
20210809_101112.jpg
20210809_101112.jpg


Steve_S
Member
# Posted: 10 Aug 2021 12:17
Reply 


The diode is in that little black box, It cannot be removed from panel nor can it be opened. Well, you can try but failure = junked panel. Some have managed to repair them but not many and I believe it has a lot to do with brands because those housing vary a fair bit.

gcrank1
Member
# Posted: 10 Aug 2021 12:48
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Steve, can an add-on diode be wired in the + or - leads out of the sealed box?

Steve_S
Member
# Posted: 10 Aug 2021 13:17
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Apparently, it is possible. There are several Youtube Vids and also threads on DIYSolarForum.

paulz
Member
# Posted: 12 Aug 2021 17:12 - Edited by: paulz
Reply 


Was walking by today and flipped one over. Covers pop right off,has diodes. Now if someone can tell me how to test with a VOA meter...
Capture_20210812.png
Capture_20210812.png


paulz
Member
# Posted: 15 Aug 2021 19:49
Reply 


So I tested these diodes today. My VOM has a diode setting, the triangle icon. For some reason these two panels have two diodes each, connected to a center tap that isn't used. See photo above.

When I tested them independently I got the correct results; .5v in one direction and open in the other. But when I test both together (at the two end terminals) I got open in both direction for some reason.

I'm going to hook an ammeter in series next, along with the CC and see what it says.

paulz
Member
# Posted: 13 Sep 2021 10:58 - Edited by: paulz
Reply 


Ha, so getting back to post #1 on this thread..

I finally put in use the array I bought to start my solar, it had been sitting stagnant as not a week later I was given the 30 panels I've been using. I have this 900w array on the shop roof now (the blue tarp is covering the PVC membrane until I find something to put over it), freeing up 12 panels I can now use up at the cabin.

It's 6 series panels x 2, puts out a bit over 100v, feeding the 150v SCC. Less juice than the other panels but I'm only working down there every few days. We'll see how it goes over winter.

I mounted casters to it, I can wheel it around for max charging but have to walk up onto the roof. Maybe with some ropes and pulleys.. Also need to lash it down if it ever gets windy here.
20210909_102441.jpg
20210909_102441.jpg


gcrank1
Member
# Posted: 13 Sep 2021 15:32
Reply 


Ropes and pulleys, I love it!
My wife makes fun of me when I haul out ropes and pulleys......

paulz
Member
# Posted: 13 Sep 2021 21:41
Reply 


Today I looked at the SCC with the array in the shade like above, about 1 amp charge. Went up there and wheeled it in the sun, 8 amps. Maybe I can leash my dog to it and teach him to keep it in the sun.

I just bought a package of 6 40w 4,500 lumen 4' LED shop lights for 100 bucks on Amazon. Put them up today. Really lights up the shop when all lit but I better take it 1 or 2 at a time where I'm working.

gcrank1
Member
# Posted: 13 Sep 2021 23:44
Reply 


Ive been replacing my ancient fluorescents with the led shop lights at home, wow, I love em! Light-weight, easy to install, no flicker or fuss.
If you can figure a window of time that you would be most likely to be using power and/or needing a recharge and positioning the array for that it might keep up without you moving it around much. Thats why mine is set SE now and I get good am recharging thru 1pm even in light overcast.

paulz
Member
# Posted: 14 Sep 2021 09:59 - Edited by: paulz
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Yeah I replaced the fluorescents in my house garage awhile ago. I bought one at Costco and realized it even has a remote, which I never use, but it turns on automatically when I walk in the garage. I like that, it's above the tool boxes which I often just drop in quickly to grab a tool out of.

There is a big stand of trees blocking the mid-morning southern sun. I get some sun earlier, then around 12-2, then more trees for the remainder.

If I do put the other 10 of my 30 panels up at the cabin I'll have more juice than I need, pretty sure. I have two inverters up there now, one inside and one outside in a box. I may try a 200' 110ac run down to the shop.

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