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36v 400 watt panels to 24v charge controller/batteries/inverter?!?

Tbleppy

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Feb 4, 2021
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I almost have my system complete but I have hit a snag. Need to know if this will work like I thought:
- twelve 12v 100 watt panels hooked up 3s 4p
- renogy 40amp 12v/24v mppt charge controller
- four 12v 100ah LiFePO4 batteries hooked up 2s 2p
- 24v 2000 watt samlex inverter pure sine wave

This is an off grid system. Im working on getting the batteries all charged fully individually so I can parallel them for 24 hours and do the final configuration 2s 2p. I have been charging the batteries with three 100 watt panels paralleled and going through the charge controller. Each battery is recommended to have 300 to 600 watts to charge it. I contacted the battery manufacturer to find out if I could charge an individual battery with my whole array. They notified me that I have set up my array to be 36v 400 watts and it can not charge the 12v battery.

Did I make a mistake? I went over this plan a lot and thought it was correct. Now I am confused. I dont care about charging the individual battery with my array. Ill figure something else out. Im concerned about the big picture here: I have a 36v configuration going to a 24v mppt charge controller and batteries 24v 200ah once configured and a 24v inverter. Was this a mistake?? Will this plan work? Thanks!
 
I almost have my system complete but I have hit a snag. Need to know if this will work like I thought:
- twelve 12v 100 watt panels hooked up 3s 4p
- renogy 40amp 12v/24v mppt charge controller
- four 12v 100ah LiFePO4 batteries hooked up 2s 2p
- 24v 2000 watt samlex inverter pure sine wave

This is an off grid system. Im working on getting the batteries all charged fully individually so I can parallel them for 24 hours and do the final configuration 2s 2p. I have been charging the batteries with three 100 watt panels paralleled and going through the charge controller. Each battery is recommended to have 300 to 600 watts to charge it. I contacted the battery manufacturer to find out if I could charge an individual battery with my whole array. They notified me that I have set up my array to be 36v 400 watts and it can not charge the 12v battery.

Did I make a mistake? I went over this plan a lot and thought it was correct. Now I am confused. I dont care about charging the individual battery with my array. Ill figure something else out. Im concerned about the big picture here: I have a 36v configuration going to a 24v mppt charge controller and batteries 24v 200ah once configured and a 24v inverter. Was this a mistake?? Will this plan work? Thanks!
Your solar panel array voltage has nothing to do with your 24V battery voltage.

Your 40A Renogy MPPT SCC 100V max input will handle your 12 100w panels connected 3S4P just fine.

3S4P is about 54Vmp and 22A

About 65Voc so well under the 100V max input.
There is nothing 36V about your 12 100w panel configuration.
Get it finished. Lol :)
No snags and Ampere time does not understand how a MPPT SCC works.
 
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I have been charging the batteries with three 100 watt panels paralleled and going through the charge controller.

Each battery is recommended to have 300 to 600 watts to charge it. I contacted the battery manufacturer to find out if I could charge an individual battery with my whole array. They notified me that I have set up my array to be 36v 400 watts and it can not charge the 12v battery.
You have 4 100Ah LFP Ampere time batteries.

You can charge One 12V 100Ah battery at a time with an array of 600w = 3S2P and the Renogy 40A SCC.
40A x 14V is 560 watts.

The 40A SCC when connected first to 1 battery will be set at 12V.
Then connect panels

12V 100Ah Ampere time can be charged at 50A so 40A will get it full fast.

You bought stuff before asking here so you did it the hard way of 12 100 watt panels 3S4P instead of 4 300 watt panels 2S2P.

4 12V 100Ah LFP 2S2P instead of 2 12V 206Ah 2S which would have been cheaper.
 
bought stuff before asking here so you did it the hard way of 12 100 watt panels 3S4P instead of 4 300 watt panels 2S2P.
Yes, I definitely made some mistakes along the way. Phew! Thanks for setting that straight for me. I also have a battery charger which I can run off a generator if needed.

I have my appliances finally so I have real numbers to work with. Can you tell me if my array would be adequate to power:


Midea WHS-160RB1 Single Reversible Compact Refrigerator, 4.4 Cubic Feet, Black​



Sonya 13.2lbs Electric Portable Compact Cloth Dryer with Stainless Steel Tub, 7 Drying Mode, White​



SPT SD-2224DS ENERGY STAR Compact Countertop Dishwasher with Delay Start - Portable Dishwasher with Stainless Steel Interior and 6 Place Settings Rack Silverware Basket for Apartment Office And Home Kitchen, Silver​


The Laundry Alternative - Silk Lux Portable Mini Automatic Washing Machine - 7.7-Pound Load Capacity - Yellow​


Portable Refrigerator Freezer - 63 Qt. AC/DC - EdgeStar​



I think it will. Freezer would be continous. Fridge can be taken off if its too much power consumption and I can do just the freezer. Obviously Id prefer both.

Id figure the washer, dryer and dishwasher at an hour per day.

I think it will. Just want to double check. Thanks!
 
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