Please Review My System Schematic for Errors

[GMB]

I want to check and make sure this is good to go before I start assembly. All parts are here sans the batteries that are still in transit from China. Please review for any errors and let me know your thoughts. Not listed is a BMS for the batteries. I am waiting for Steve_S to get his Chargery unit hooked up and a review done before I order since I am new to battery building and would like to mimic his build. Until then I will hook up a battery low voltage monitor with an alarm buzzer - just in case, and also monitor daily with multimeter. The goal is to run the AC unit during the summer for about 15-20 minutes every hour as needed to cool an insulated small room (only during the day; it's cool at night where I am). The freezer units pull about 350 watts when the motor kicks on and the one rigged as a refrigerator barely ever kicks on, so I believe this will be more than enough solar and battery to keep it all going. I am in Arizona with ample sunshine. I will also put in an earth ground and make sure everything is grounded properly. Note - the font makes a 5 look like a 3, but I have (10) 350 watt panels in total.

 

[Steve_S]

Looks Good, but for one thing. You have AWG 2 for battery to Inverter would be much better if you used 2/0 NOT AWG 2. My first 3kw system was quite similar and believe me, when I say use 2/0.

BTW, I AM running a Chargery BMS8T with the ShunBin Pack I have installed and it works exactly as It should, even the low temp cutoff works as I tested it. I do have two more I will be using with my 24V/280AH packs I'm building and I have another one to order yet for when I split the ShunBin pack up into independent 175AH packs.

 

[tictag]

Some considerations:

1. Your PV cable might be over-spec'd. Your 2S3P array will generate 21.8A in normal operation, which can be safely serviced with 14AWG cable. That said, voltage drop may be a factor so 10AWG may well be appropriate.
2. The cable from surge protector to SCC is over-spec'd. 6AWG is rated for 95A but it will only be carrying a maximum of 25A (i.e. in a short circuit scenario) and only 21.8A in normal operation.
3. The cable from the SCC to your battery is over-spec'd. 2AWG cable is rated for 170A but will only be carrying a maximum (i.e. in perfect solar conditions) of 87.5A. Distance / volt-drop may be a consideration.
4. I personally would maximise solar power delivery efficiency and minimise project cost (cheaper cable/connectors) by connecting your array in a 3S2P configuration (128.1Voc).
5. Your 2AWG cable from battery to inverter is slightly over-spec'd but should be suitable.
6. Your 2AWG cable from battery to inverter is only rated for 170A but you're protecting it with a 200A fuse.
7. Your LG AC unit is rated at 1,380W but could surge to 4,140W on startup. Be sure your Giandel inverter supports this. I don't have specs for the chest freezer but just be sure your inverter supports its surge load.
8. Your comment, "3500 Watts of Solar" is incorrect. 350W x 6 panels = 2,100W.
9. Your comment, "13,440 Watt Hours of Battery" is incorrect. 16 x 3.2V / 280AH cells = 14,336Wh.

Hope this helps.

 

[JoeHam]

Some considerations:

8. Your comment, "3500 Watts of Solar" is incorrect. 350W x 6 panels = 2,100W.
9. Your comment, "13,440 Watt Hours of Battery" is incorrect. 16 x 3.2V / 280AH cells = 14,336Wh.
Hope this helps.

I see 10 panels listed for a total of 3500 W

I suspect a typo where you write 16 x 3.2 / 280 AH which of course should be 16 x 3.2 x 280AH and of course the answer is still 14,336Wh

 

[GMB]

Some considerations:

1. Your PV cable might be over-spec'd. Your 2S3P array will generate 21.8A in normal operation, which can be safely serviced with 14AWG cable. That said, voltage drop may be a factor so 10AWG may well be appropriate.
2. The cable from surge protector to SCC is over-spec'd. 6AWG is rated for 95A but it will only be carrying a maximum of 25A (i.e. in a short circuit scenario) and only 21.8A in normal operation.
3. The cable from the SCC to your battery is over-spec'd. 2AWG cable is rated for 170A but will only be carrying a maximum (i.e. in perfect solar conditions) of 87.5A. Distance / volt-drop may be a consideration.
4. I personally would maximise solar power delivery efficiency and minimise project cost (cheaper cable/connectors) by connecting your array in a 3S2P configuration (128.1Voc).
5. Your 2AWG cable from battery to inverter is slightly over-spec'd but should be suitable.
6. Your 2AWG cable from battery to inverter is only rated for 170A but you're protecting it with a 200A fuse.
7. Your LG AC unit is rated at 1,380W but could surge to 4,140W on startup. Be sure your Giandel inverter supports this. I don't have specs for the chest freezer but just be sure your inverter supports its surge load.
8. Your comment, "3500 Watts of Solar" is incorrect. 350W x 6 panels = 2,100W.
9. Your comment, "13,440 Watt Hours of Battery" is incorrect. 16 x 3.2V / 280AH cells = 14,336Wh.

Hope this helps.

Thank you for the advice tictag. I think I should of used a different font, but the chart reads 2s5p for the panels. I have (10) in total of the 350 watt panels.
For the 2 AWG wire, I used this chart from Windy Nation that shows a maximum amperage of 205 amps, thus the 200 amp fuse. However, I do like Steve_S's recommendation of upgrading that to 2/0 wire, so I will implement that change.

I used a killawatt meter on the AC unit and didn't notice a huge spike on start up. Also, it was being used in a house with only a 15 amp breaker, so hopefully the Giandel can handle it. I believe it has a 20 amp fuse for each outlet, but I will double check. Not tested yet with solar since I still need the batteries to arrive before full assembly. I may send this 3000 watt unit back and upgrade to the 4000 watt unit though just in case. Too bad Victron doesn't make a 24v 4000 watt inverter because that is what I would really prefer.

For the total watt hours of the system, I mistakenly did 24 volts x 560, instead of doing it correctly. I will update that now.

 

[GMB]

Looks Good, but for one thing. You have AWG 2 for battery to Inverter would be much better if you used 2/0 NOT AWG 2. My first 3kw system was quite similar and believe me, when I say use 2/0.

BTW, I AM running a Chargery BMS8T with the ShunBin Pack I have installed and it works exactly as It should, even the low temp cutoff works as I tested it. I do have two more I will be using with my 24V/280AH packs I'm building and I have another one to order yet for when I split the ShunBin pack up into independent 175AH packs.

Thank you for the suggestions Steve. I am going to upgrade the inverter to the 4000 watt model just in case since I can still return this one for free, so the 2/0 wire size seems like a no brainer. Also, the 4000 watt unit has 4 outlets instead of 2. I'll also update that to a 250 amp fuse instead of a 200 to go with the bigger wire size.

Updated the schematic with the changes.