I need to order breakers/fuses for my current (and evolving) solar build. Hoping for final sign-off or correction so I can sleep well knowing it's all well-protected.
PV: My understanding is that I don't need fuses in-between panels when wired in series or 2 (or fewer) in parallel. That leaves a main fuse between panels and MPPT/AIO. Breakers just after those, between fuse and MPPT/AIO.
PV:
PV WIRE: 10awg solar wire for all connections.
PANELS:
ISC: 10.31a
VOC: 49.03v
Panel configuration 1 (Growatt): 2p2s, Each string <15ft to t-connector & combiner box, ~15ft into RV/Growatt
156% ISC for 2p2s configuration: 32.17a
Panel configuration 2 (Renogy Rover): Single Panel, <10ft to combiner box, ~15ft into RV/Renogy Rover
156% ISC: 16.08a
FUSES:
No fuses needed according to Solar Array OCP doc shared on this forum
Breakers:
CHTAIXI DZ47Z-63 2-pole breaker (Overkill on amperage, but same price as lower amperage breakers; using for both strings)
BATTERY:
CURRENT BATTERY CONFIGURATION: 8-24v20ah batteries in 8p configuration (160ah) — (cell design is Headway 38120S (nominal 3.2v10ah) 2p8s configuration with custom BMS)
WIRE: 1/0 gauge, <5ft pos, <5ft neg (is this high enough gauge for my use? My inverter (Growatt) is currently only able to draw 3000w/6000w peak, so I think I'm ok here with the run length).
FUSES: 200a class t fuse (busman, littelfuse, blue sea?) immediately off of the positive busbar.
BREAKERS/BATTERY DISCONNECT: Not sure what to do here. Breakers seem iffy, and fuses are said to be the heavy lifter in the event of a battery overload. I'm inclined to use a simple rotary disconnect like this Blue Sea 6006 m-Series battery disconnect for occasional manual shutoff just after the fuses. If there's a better known approach to breakers/disconnects, please educate me.
I am currently cap testing all Headway cells (many were lightly used and are testing above rated specs), and will likely build a few larger batteries out of the best cells. This will no doubt affect my wire/fuse requirements, so if you have guidance on protection for this near-future battery design, I'd be really grateful. Specifically, I am unsure whether I need to wire for max load potential (Growatt), or for total battery capacity. Here's that rough configuration plan:
FUTURE BATTERY CONFIGURATION: Raw Headway 38120S (nominal 3.2v10ah) cells in ~16p8s configuration, custom BMS/active balancer on each battery, in 2p or 3p configuration (~160ah per battery * 3 = nominal 24v480ah)
PV: My understanding is that I don't need fuses in-between panels when wired in series or 2 (or fewer) in parallel. That leaves a main fuse between panels and MPPT/AIO. Breakers just after those, between fuse and MPPT/AIO.
PV:
PV WIRE: 10awg solar wire for all connections.
PANELS:
ISC: 10.31a
VOC: 49.03v
Panel configuration 1 (Growatt): 2p2s, Each string <15ft to t-connector & combiner box, ~15ft into RV/Growatt
156% ISC for 2p2s configuration: 32.17a
Panel configuration 2 (Renogy Rover): Single Panel, <10ft to combiner box, ~15ft into RV/Renogy Rover
156% ISC: 16.08a
FUSES:
No fuses needed according to Solar Array OCP doc shared on this forum
Breakers:
CHTAIXI DZ47Z-63 2-pole breaker (Overkill on amperage, but same price as lower amperage breakers; using for both strings)
BATTERY:
CURRENT BATTERY CONFIGURATION: 8-24v20ah batteries in 8p configuration (160ah) — (cell design is Headway 38120S (nominal 3.2v10ah) 2p8s configuration with custom BMS)
WIRE: 1/0 gauge, <5ft pos, <5ft neg (is this high enough gauge for my use? My inverter (Growatt) is currently only able to draw 3000w/6000w peak, so I think I'm ok here with the run length).
FUSES: 200a class t fuse (busman, littelfuse, blue sea?) immediately off of the positive busbar.
BREAKERS/BATTERY DISCONNECT: Not sure what to do here. Breakers seem iffy, and fuses are said to be the heavy lifter in the event of a battery overload. I'm inclined to use a simple rotary disconnect like this Blue Sea 6006 m-Series battery disconnect for occasional manual shutoff just after the fuses. If there's a better known approach to breakers/disconnects, please educate me.
I am currently cap testing all Headway cells (many were lightly used and are testing above rated specs), and will likely build a few larger batteries out of the best cells. This will no doubt affect my wire/fuse requirements, so if you have guidance on protection for this near-future battery design, I'd be really grateful. Specifically, I am unsure whether I need to wire for max load potential (Growatt), or for total battery capacity. Here's that rough configuration plan:
FUTURE BATTERY CONFIGURATION: Raw Headway 38120S (nominal 3.2v10ah) cells in ~16p8s configuration, custom BMS/active balancer on each battery, in 2p or 3p configuration (~160ah per battery * 3 = nominal 24v480ah)