Please check my simple off-grid plan

[solitarysecluded]

Hey guys. After spent some time reading here and Youtube videos, I'm about to finalise my solar plans. However still got few questions on other components before I get em.

I'm running 220-240V for all appliances and not feeding back to the grid nor attached on grid.

9 solar panels on each inverter. Vmp : 38.11V 25A good? How many breakers do we need besides PV isolator..?

I got two SPF 5000, two 51.2V-280ah battery banks and one 51.2V-100ah battery rack. The wire connection it's on 1AWG 50mm(largest I can get) although Growatt recommends 2AWG. 3 battery banks will parallel on 300A busbar, wire length 2 meter.

I have questions on DC breaker. It will placed close to inverters before going through to busbar and battery banks. I plan to use this type instead of Class-T fuse as it's hard to get at my place. The seller recommends me to get 600A. Usually I saw people mentioned 250A. Well I'm lost here. Btw, each battery already has it's own 150A breaker.

I wondered what AC breaker I should get? RCBO 63A, 25A? Just a tiny house with low daily consumption around 3kWh+.

Is my setup doable in long run? I try keep it as simple as possible. Thanks!

 

[MisterSandals]

I got two SPF 5000,

What is max Voc it can handle?
What is Voc of your panels?
What is coldest temp array will encounter? Temp drop below where panels are rated (25C) increases voltage. Folks use record low temps but you can choose the temp your system can handle.

9 solar panels on each inverter. Vmp : 38.11V 25A good?

is this 3S3P config array?
3 or more strings in parallel need to be fused.

two 51.2V-280ah battery banks and one 51.2V-100ah battery rack.

LiFePO4?

 

[solitarysecluded]

What is max Voc it can handle?
What is Voc of your panels?
What is coldest temp array will encounter? Temp drop below where panels are rated (25C) increases voltage. Folks use record low temps but you can choose the temp your system can handle.

is this 3S3P config array?
3 or more strings in parallel need to be fused.

LiFePO4?

Thanks for the reply Mister.

Inverter max Voc is 450 and 45.13V on 410w panel. Weather range 18c - 28c annually. Average close 24c.

It started off with 9S1P each inverter and eventually to 9S2P each inverter. 36 panels at the end of this setup.

Yes all LiFePO4. 3 battery banks in parallel. Total 660A I guess

 

[solitarysecluded]

Seems like my newbie questions is too lengthy lol

Appreciate if any of you can share your 240V setup. So I can just copy it. Most system I've come across is split phase 120V setup.

 

[solitarysecluded]

90 views. Anyway, saw some folks mentioned a formula.. 5000/48/.85 x 1.25

Will and David tried Nader 200A breaker on their setup IIRC.

Well I guess I get two units of this 250A breaker with 25,000 breaking capacity on each inverter.

 

[solitarysecluded]

I'll share with others once I figure out breaker for 9S2P panels and AC single phase.

 

[Hardergamer1]

I would re-explain your whole setup with the specifications, and then ask separate questions for each part of your build.

 

[solitarysecluded]

Hey. Ya mainly about breakers. Finalising.

You may check out if they are good for my system

From panels to inverters : Two units of 32A DC1200V PV Isolator switch.

From inverter to busbar : Two units of 250A 2P Molded breaker.

Battery itself comes with own 150A breaker. I guess that's it?

 

[solitarysecluded]

I'm about to buy em and some expert pointed it may not "suitable" / bi-directional etc.

The orientation coming from battery is at top of breaker

 

[Hardergamer1]

If the total amps from the panels is 25a then that isolator will work fine, and is what I have used,

And the breakers are fine, but I do not know if they are up to US code? But Taixi are ECC coded, are you going to add a DZ47 breaker after the busbars to each item like the inverter MPPT and battery charger?

 

[solitarysecluded]

If the total amps from the panels is 25a then that isolator will work fine, and is what I have used,

Cool thanks. Mine around 22A with 9S2P per inverter.

And the breakers are fine, but I do not know if they are up to US code? But Taixi are ECC coded, are you going to add a DZ47 breaker after the busbars to each item like the inverter MPPT and battery charger?

Yes. Inverter AIO >> 250A DZ47 >> 300A Busbar >> 660Ah Battery banks

Some folks here said Taixi DZ47 1P is bi-directional. I'm not sure if it's important to have a bi-directional breaker

 

[rodrick]

48 volt systems should have class t fuses

 

[solitarysecluded]

48 volt systems should have class t fuses

It's not easy to get it at my place, moreover price quite steep.

Heard lots people including Andy using breaker as it has higher rate than fuse and can work as switch as well. Correct me if I'm wrong. Cheers.

 

[rodrick]

the Fuse is more of a positive safety also make sure your breaker is rated to open under a load if using as a switch a lot of these cheaper breakers are questionable

 

[solitarysecluded]

the Fuse is more of a positive safety also make sure your breaker is rated to open under a load if using as a switch a lot of these cheaper breakers are questionable

You do have a point. I could add fuse on top of breaker as switch.

What do you think of this Class T Fuse 225A? Only able to find this near my place.

 

[tinyt]

You do have a point. I could add fuse on top of breaker as switch.

What do you think of this Class T Fuse 225A? Only able to find this near my place.

You will still need to buy the fuse itself.

 

[solitarysecluded]

You will still need to buy the fuse itself.

I've checked the main site, seem like the holder comes with fuse.

 

[rodrick]

I think that is good insurance to protect against a major smoke show with flames

 

[timselectric]

It's not easy to get it at my place, moreover price quite steep.

Heard lots people including Andy using breaker as it has higher rate than fuse and can work as switch as well. Correct me if I'm wrong. Cheers.

All breakers, and no fuses in my system.
I always prefer breakers over fuses. They are double duty. (Protection and disconnect) And prefer to reset rather than replace. (At a cost)

 

[solitarysecluded]

All breakers, and no fuses in my system.
I always prefer breakers over fuses. They are double duty. (Protection and disconnect) And prefer to reset rather than replace. (At a cost)

Oh my. I'm heading to similar setup as yours. SPF 5000 parallel, close capacity on solar & batteries.

Would be awesome if you could share what kind of breakers you use?