| << . 1 . 2 . |
| Author |
Message |
paulz
Member
|
# Posted: 24 Oct 2022 05:41pm
Reply
Question: Can two separate, non-matching panel/controller systems be connected to the same battery bank?
At my shop I have a couple of panels, 48V I think, connected to an Epever MPPT controller, charging a LA deep cycle battery. I also have another array, 36V, going to a Renogy Rover MPPT charging an identical battery. They both only get about a max of 5A charge at peak sunlight. One setup powers an inverter for the shop lights and saws, the other a couple of cameras and a radio. It's OK separate but together would give me more reserve for power tool operation.
|
|
Fanman
Member
|
# Posted: 24 Oct 2022 06:29pm
Reply
Quoting: paulz Question: Can two separate, non-matching panel/controller systems be connected to the same battery bank?
Pretty sure the answer is no... the charge current is determined by the batter voltage, but if one controller is seeing the higher charge voltage coming from the other controller, it would cause problems. At best the batteries might not charge, at worst it might damage one or both of the controllers.
|
|
FishHog
Member
|
# Posted: 24 Oct 2022 08:26pm
Reply
sure you can Paul. I do it all the time. I have 2 setups, one charges batteries for my trolling motor. When they are charged up, I swing the charge controller over to my house batteries if needed on low sun days.
|
|
ICC
Member
|
# Posted: 24 Oct 2022 09:22pm
Reply
Two or more input systems are entirely feasible even if the panels and controllers are different. What matters is to have controllers that have or can have their bulk/absorb settings programmed to the same values. I use 3 arrays; east, south and west facing. Three controllers. One battery bank.
|
|
paulz
Member
|
# Posted: 29 Oct 2022 06:00pm
Reply
Ok so I doubled up on the SCCs to the shop bank yesterday and it's doubled the input. Should be enough to sustain the batts for the few things that run down there full time this winter.
Thanks guys.
|
|
Steve_S
Member
|
# Posted: 30 Oct 2022 08:39am
Reply
Attached is a schema for parallel batteries with Charge Controller, Charger and Inverter. I've attached this schema for clarity purposes.
The charger can be another SCC or an actual hardwired charger system (ie Meanwells).
Not shown in Schema is a Pre-Charge circuit for the inverter. This is an essential item to have in place when using Lithium Based Batteries.
When cold starting an Inverter/Charger the capacitors draw a Huge Spike for a second or two (depending on the size of the inverter & its Capacitors) from the battery bank before it can start, "the spark" generated by that can fuse breakers and even damage your batteries as it is a huge pull. The pre-charge allows for the capacitors to precharge via a resistor to prevent that large surge and subsequently "the spark" keeping your gear safe.
|
|
paulz
Member
|
# Posted: 30 Oct 2022 10:20am - Edited by: paulz
Reply
My Wifi router died day before yesterday, pretty sure it had to do with my reconfig. It runs on 12vdc. When I first finished the reconfig I switched the inverter and Meanwells on, then the all the 12v stuff, no problem. I think what blew the router was later toggling the inverter and MW circuit breaker with the router still powered up (I was curious about their current draw). Going to have to be careful with that, or do the pre-charge circuit.
Luckily the internet company tech was working two miles away where someone digging had severed their cable, and he had a new router on his truck. We were back up about an hour later to watch the World Series right at first pitch.
|
|
gcrank1
Member
|
# Posted: 30 Oct 2022 07:22pm
Reply
I have got some pretty heathy cap-flashes hooking up the MW. That seems to be solved by plugging it into ac power first, which loads the caps, then hooking up the LFP.
Is that Ok?
If not, my thought is to load the caps by attaching a small older LA battery for a few seconds then disconnect it and attach the LFP.
|
|
|
paulz
Member
|
# Posted: 30 Oct 2022 08:19pm
Reply
That's how I always did it until I moved them into the cabin this week and hard wired to the batts, with the AC cord going outside to plug into the genny.
I just shut the generator off, had it running about an hour. At 13.0v, charge was 42A, gradually decreased to about 30 when I shut it off, 13.3 now. The two MWs together should do 80A, it seems the batts would have to be well into the 12v range to get any more amps into them quicker. Not sure I want to try that.
|
|
gcrank1
Member
|
# Posted: 31 Oct 2022 09:52am - Edited by: gcrank1
Reply
Since I am charging at home on grid with the MW and time doesnt matter I just set the MW today back at 13.7v as per Steve_S.
I will watch the V and A meters for the amps delivered at that setting and how long before the fall off to 5a.
Question now is how long at that 5a or less?
|
|
paulz
Member
|
# Posted: 1 Nov 2022 09:48am
Reply
When I first got mine and was bringing back to the grid for charging, I had the MW set to 14.6 (per the Valence specs). I'd start it in the afternoon and leave it overnight. Once it got into the 14s the amps would fall off to almost nothing.
|
|
| << . 1 . 2 . |
