Component Distances

[Neon]

Due to compartment sizes and the very large sizes of the batteries and Victron components , I may have to place the MPPT charge controllers in another bay.

So, the solar panels will be approximately 12 foot from the MPPTS (8 AWG). Each MPPT will control (2) 425 Watt panels connected in series with an open circuit voltage of 48.1 V each panel.

Each set of series panels will be connected to a Victron 150/70 controller. I am thinking of putting the MPPT’s approximately 12 foot from the batteries using 2 AWG wire.

Anyone see any issues with this distance from the batteries?

 

[rmaddy]

2AWG wire will handle the 70A and keep the voltage drop under 3% for that distance to the batteries. I don't see a problem.

Note that if you used a 24V battery bank instead of 12V then you could use one 150/70 for all 4 panels (in 2S2P) or use two 150/35 controllers instead of two 150/70. The 150/35 would only need 6AWG to the batteries.

 

[chrisski]

Please check the max wire size for your controller. I have a Victron 100/50, and the max wire size is 6 AWG. I wanted thicker wire size for voltage loss but could not fit it The Victron terminals.

You can do things like fold over teh 6 AWG wire and butt splice something thicker like 4 or 2 AWG, but who knows if that splice will give you more voltage loss than just 6 AWG wire or become a failure point years down the road.

 

[rmaddy]

Please check the max wire size for your controller. I have a Victron 100/50, and the max wire size is 6 AWG. I wanted thicker wire size for voltage loss but could not fit it The Victron terminals.

The spec sheet for the 150/70 states it handles up to 2AWG for the battery connections.