Solar Panel Charge Controllers

Dougal

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Curious if anyone here can answer this for me…
It seems the vast majority of budget charge controllers for solar panels, wherever one buys them, are all made by the same company in China (no surprise there then). Hence the manuals leave a vast amount to be desired!

I have a ‘dual battery’ controller (EPIPDB 20Amp) waiting to be installed, and my boats wiring (love it or hate it), is a very simple two bank system. One 110Ah cranking battery and two 95Ah domestic (paralleled) batteries. There is no split charge relay or electronics etc, just the old 1, 2, Both, Off switch (which I love, so no comment please).

My question…. Being a dual output model, there are obviously two sets of charging wires. HOWEVER, what happens when the battery switch goes to ‘BOTH’ (all THREE batteries paralleled)? My guess would be the controller then ONLY sees whatever is connected to the BAT1 terminal?

Thoughts please?
 
Curious if anyone here can answer this for me…
It seems the vast majority of budget charge controllers for solar panels, wherever one buys them, are all made by the same company in China (no surprise there then). Hence the manuals leave a vast amount to be desired!

I have a ‘dual battery’ controller (EPIPDB 20Amp) waiting to be installed, and my boats wiring (love it or hate it), is a very simple two bank system. One 110Ah cranking battery and two 95Ah domestic (paralleled) batteries. There is no split charge relay or electronics etc, just the old 1, 2, Both, Off switch (which I love, so no comment please).

My question…. Being a dual output model, there are obviously two sets of charging wires. HOWEVER, what happens when the battery switch goes to ‘BOTH’ (all THREE batteries paralleled)? My guess would be the controller then ONLY sees whatever is connected to the BAT1 terminal?

Thoughts please?

That sounds reasonable to me. Either way, I can't see that it will do the controller any harm if all the batteries are paralleled. I have mine 80% to Bat1 and 20% to Bat2 so Bat1 will probably just assume command.

Richard
 
A question I had never considered as I never use 'both'. I have just tried it, with the domestic bank charging at 12.9 volts, starter battery resting at 12.8 volts. Turning the switch to 'both' brought the starter battery to 12.9 volts. As I was typing the fridge came on, reducing the domestic bank voltage to 12.7 volts. Switching to 'both' had no effect, starter battery still showing 12.8 volts but I didn't leave it like this for long, so maybe the starter battery voltage would have dropped to match domestic in time. These values all read from the solar controller.

When the engine is charging it prioritises the domestic bank and all the solar goes to the starter battery. In my case starter is 1, domestic 2.
 
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