here's my system diagram. modified from the "off-grid king"

[starchy]

did i get anything wrong? my roommates an electrician and said it looked alright.

 

[starchy]

50 amp fuses to the solar charge controllers and a 315 amp fuse to the inverter, fuse block and batteries.

 

[Diysolar123]

hard to tell what the little black boxes are in my old age even with zoom hehe; two things to mention:
1)how about a battery thermal disconnect?
I like to have a bms on my battery pack, then fuses on both poles for those special moments whenthe BMS decides to handle a short by fusing itself with a short, THEN a DC disconnect on the bat+. This makes the battery bank safety somewhat self contained. It is always handy to have a quick method to cut the battery out of the circuit.

2)regarding the MPPT charge controllers
if those are being paralleled, don't those have to be special with a synchronizing port connecting the controllers all together to work on parallel?
somewhat like paralleling inverters, they have to know about each other or "bad things may happen".

 

[DerpsyDoodler]

50 amp fuses to the solar charge controllers and a 315 amp fuse to the inverter, fuse block and batteries.

Need disconnects for the batteries (after the battery positive fuse) and for the solar panels.

 

[Ironman]

I'm curious as to whether my wiring will pass the experience inspection.
I plan to have 2 battery setups that are identical, and to parallel them just before the shunt breaker.

 

[Off Gridin' It]

Why not running the panels 6S 2P. It would save you a lot of wire and you would only need 1 charge controller which would save you a lot of space. Honestly spending the money on three 40 amp charge controllers could cost more then on larger charge controller. A 100 amp charge controller could easily handle 1200 watts Making your install MUCH MUCH cleaner and simpler and possibly cheaper.

 

[Q-Dog]

100 watt panels in 2S2P won't push 20 amps. Why the 40 amp charge controllers?

 

[Off Gridin' It]

100 watt panels in 2S2P won't push 20 amps. Why the 40 amp charge controllers?

Right. At most it may produce 10 to 12 amps.

 

[starchy]

@Q-Dog, christians camper: idk, cuz i based this on "the off grid king" where he has 4 on a single 40 amp controller. i appreciate the insight tho i've already bought all the big components so i'll prolly just proceed as planned rather than returning stuff.

@Diysolar123 and derpsydoodler: disconnects like this?

Amazon.com: Battery Disconnect Switch with 2 Keys - JOYHO 6V 12V 24V Battery Kill Switch, Isolator Cut Off Power for Marine Boat RV ATV Auto Truck,On/Off 2 Position, Waterproof Cover for Key Hole : Automotive

Buy Battery Disconnect Switch with 2 Keys - JOYHO 6V 12V 24V Battery Kill Switch, Isolator Cut Off Power for Marine Boat RV ATV Auto Truck,On/Off 2 Position, Waterproof Cover for Key Hole: Battery Switches - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

sorry i'm so clueless. total n00b.

 

[Freep]

Is this going to be a stationary build or mobile? If it's for an off grid house you might want to consider going 48V for the battery, depending on what kind of AC loads you're going to have.

 

[Freep]

: idk, cuz i based this on "the off grid king" where he has 4 on a single 40 amp controller. i appreciate the insight tho i've already bought all the big components so i'll prolly just proceed as planned rather than returning stuff.



sorry i'm so clueless. total n00b.

In the future you might want to ask questions before you pull out the credit card.

 

[starchy]

re:

hard to tell what the little black boxes are in my old age even with zoom hehe; two things to mention:
1)how about a battery thermal disconnect?
I like to have a bms on my battery pack, then fuses on both poles for those special moments whenthe BMS decides to handle a short by fusing itself with a short, THEN a DC disconnect on the bat+. This makes the battery bank safety somewhat self contained. It is always handy to have a quick method to cut the battery out of the circuit.

2)regarding the MPPT charge controllers
if those are being paralleled, don't those have to be special with a synchronizing port connecting the controllers all together to work on parallel?
somewhat like paralleling inverters, they have to know about each other or "bad things may happen".

2) idk tbh. they're all the exact same controller so i was hoping they'd play nice without any extra effort.

 

[starchy]

Is this going to be a stationary build or mobile? If it's for an off grid house you might want to consider going 48V for the battery, depending on what kind of AC loads you're going to have.

mobile. ram promaster. why go 48? the ac load's kinda big, i guess.

 

[DerpsyDoodler]

@Q-Dog, christians camper: idk, cuz i based this on "the off grid king" where he has 4 on a single 40 amp controller. i appreciate the insight tho i've already bought all the big components so i'll prolly just proceed as planned rather than returning stuff.

@Diysolar123 and derpsydoodler: disconnects like this?

Amazon.com: Battery Disconnect Switch with 2 Keys - JOYHO 6V 12V 24V Battery Kill Switch, Isolator Cut Off Power for Marine Boat RV ATV Auto Truck,On/Off 2 Position, Waterproof Cover for Key Hole : Automotive

Buy Battery Disconnect Switch with 2 Keys - JOYHO 6V 12V 24V Battery Kill Switch, Isolator Cut Off Power for Marine Boat RV ATV Auto Truck,On/Off 2 Position, Waterproof Cover for Key Hole: Battery Switches - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

sorry i'm so clueless. total n00b.

this one, but choose one that is not dual circuit.

https://www.amazon.com/dp/B000K2MCR2/ref=cm_sw_r_cp_api_glt_fabc_4YKYKR6CQTSGZPQT48VA