Lwiddis wrote:
It’s all about how much loss you are willing to accept. I want 2% or less from panels to controller.
Lwiddis,
Thank You for your service, but this is an issue I run into all the time in boat wiring work.
The tables all publish voltage drop as Percent(%) and that is just plain wrong. The system voltage drop is VOLTS... This is true what ever the system voltage is. Many solar systems run greater than the 13.6 nominal for charging a 12V system. That voltage drop can still cripple a system even when the percentage of the system voltage is small.
I simple terms, for low voltage systems, always buy all the copper you can afford. You only have to buy it once, but if you don't you will pay for it for the life of the system.
Matt
