2000w 24v 5s2p (Please check)

[kenkoh]

Does this work?

 

[John Frum]

Suggest you put a means of disconnect between the panels and the solar charge controller.
replace the breaker beween the solar charge controller and the battery with a 90 amp fuse.
70 amps * 1.25 fuse headroom = 87.5 amps
replace the fuse between the inverter and the battery with a 90 amp.
That way you need to have less spares.

 

[kenkoh]

Suggest you put a means of disconnect between the panels and the solar charge controller.
replace the breaker beween the solar charge controller and the battery with a 90 amp fuse.
70 amps * 1.25 fuse headroom = 87.5 amps
replace the fuse between the inverter and the battery with a 90 amp.
That way you need to have less spares.

Thanks so much I forgot all that. Should the panel disconnect be 1p or 2p?

 

[kenkoh]

Suggest you put a means of disconnect between the panels and the solar charge controller.
replace the breaker beween the solar charge controller and the battery with a 90 amp fuse.
70 amps * 1.25 fuse headroom = 87.5 amps
replace the fuse between the inverter and the battery with a 90 amp.
That way you need to have less spares.

Disconnect go on the positive wire correct?

 

[John Frum]

Disconnect go on the positive wire correct?

Sure or both.
One of the pv experts can probably say better.

 

[kenkoh]

Sure or both.
One of the pv experts can probably say better.

Thank you.

 

[Forbisher]

Does this work?

You are wise to plan your system before buying anything. Nice diagrams.
But you have jumped from a 1000w of panels to 2000w which suggests that you have really not figured out how much power you need.

Also I doubt if you will find cheap 200w panels on Craigslist or eBay etc so you will be still paying about $1 a watt like those 100w panels.
Cheap panels are usually 250w or larger.

How about laying out the math that you used to make the diagrams and use the voltage drop calculator to size the panel cables.
I don't know what the price difference is between 8 AWG and 10 AWG is but under 2% drop is good.

Also being a cheapskate I would buy a cheaper battery than Battle Born if I was getting 2 and i own a Battle Born.
SOK batteries would save you about $800 on two and DIY even more.

 

[GXMnow]

Battle Born only recommends a 50 amp charge rate. In full sun with a light load on the inverter, this could be stressing the batteries a bit. Most LiFePo4 cells don't like much more than 0.5C charge rates. They can take up to 100 amps for a short time, but you may want to dial down the charge controller for long life. On the flip side, if you always have at least 200 watts of load, then it is not a problem, but something to keep in mind.

I also agree, there are much cheaper batteries than Battle Born, but they are well made with good support. So you need to decide where to spend your money. Also keep in mind to buy matched pairs when running them in series. The internal BMS in those batteries can only balance across the 4 cell groups inside. If the capacities differ, one 12 volt bank could hit high or low limit before the other. Victron and others do make balancer units to balance 12 volt batteries in series. It is not a bad idea for a setup like this. If you go the discrete LFP cells route, use an 8S BMS to balance across the whole bank.

 

[kenkoh]

Suggest you put a means of disconnect between the panels and the solar charge controller.
replace the breaker beween the solar charge controller and the battery with a 90 amp fuse.
70 amps * 1.25 fuse headroom = 87.5 amps
replace the fuse between the inverter and the battery with a 90 amp.
That way you need to have less spares.

One more thing - what amp size disconnect would work well for my setup?

 

[John Frum]

One more thing - what amp size disconnect would work well for my setup?

At least 1.25 times the panel amperage up to the ampacity of the wire.
Also has to be rated for the voltage.
I think the alt-e store has breakers that you could use.