Required Wire Size AWG

[NVCYberPro]

Hello,

I am planning my off grid solar system, I am currently on grid and intend to pull the plug. I will need to do this is steps so my plan is as follows.

I have a 6 circuit Generator Transfer switch installed next to my main panel (200 Amp) in my laundry room. I want to extend the wiring for the Emergency Generator input for those 6 circuits downstairs in the basement where my Inverters and batteries will be mounted. This run is an estimated 35 feet and I have been calculating 50 feet for safety.

Since I plan to pull the plug and go off grid - I want to size the wiring to the basement to handle the final load, not just run the 50 amps from the generator.

The plan is to use 2 LV6548's or EG4's or similar devices in parallel to provide 120/120 split phase. All the data I have indicates I would use 4 AWG from each inverter to a sub panel mounted in the basement, those units only allow for a 4 AWG wire. If I am doing my calculations correctly I would need to run 1 AWG or 1/0 AWG from these units to the main panel upstairs. Is that correct and if so, how do I do that and convert from the 4 AWG (Ground, Neutral, L1 & L2) from the inverters to 1 AWG or 1/0 AWG run upstairs.

Again the first step would be to wire these to the input of the Generator transfer switch. When the system is 100% built out we would disconnect from the utility and connect the output of the basement inverters into the main panel. I would like to run the correct wire upfront instead of rewiring later.

Thank you

 

[Supervstech]

It depends on the amperage you are planning for.
How many inverters are you planning to setup?

 

[BentleyJ]

I would suggest performing a full audit of your present and future power needs as then size PV array, inverter(s), batteries, breakers and wiring.

As to your specific question, "converting multiple runs of smaller gauge wire to 1 larger wire" There are 2 ways.
1) Use a combiner box with multiple breakers that are tied together with a "finger" style bus bar. Midnight Solar is a good source and also look at the Schneider Power Distribution Panel for an example of "how its done". There are several YT videos showing various stages of wiring up a PDP which has both the DC and AC connections as well as low voltage communication cables in one box.
2) Build you own PDP with DIN rail or panel mount breakers and use Power Distribution Blocks to make the wiring transitions.

https://www.homedepot.com/p/ILSCO-Power-Distribution-Block-Connector-Modular-Design-Line-Conductor-Range-2-0-14-PDA-14-2-0-1-EC/317173741.

If you are planning to go off grid that's a big decision and reliability is key. I would suggest researching some of the higher end inverters like Schneider and Sol-Ark.