multiple charge controllers

[DualFuel]

I have three seperate solar panel/ C60 Xantrex charge controller systems. The systems are spread out all over the property at various places. During the winter, I would rather gather everything together.
Could two charge controllers be hooked up to the same battery bank? I don't read anything preventing it in the literature.
DF

[birdhouse]

the simple answer is yes.  multiple charge controllers can be used on the same bank.  it is however important to understand how each one works and what the setpoints are set at. 

some more details from what you're trying to do would help to give a better answer.  maybe one CC could even do it all if conditions are right. 

adam

[dnix71]

I have 2 MPPT's hooked up to the same bank. They each have their own panels. The only catch may be that my MPPT's bridge the panel ground and battery ground.  That means the 2 controllers share a common ground. If the controllers use PWM then the pulses from each unit can ring back into each other.

That hasn't been an problem for me.

The other issue is where you set the float voltage on each unit. If you don't set them very close to each other, one will quit before the other and the other will be doing most of the final charging. If one was a 2 stage and the other 3 stage, then the 2 stage should be set to cut off just a little before the 3 stage unit.

[DualFuel]

 The big plan here is pretty simple. I have one camp up high in the wind that doesn't need the solar panels in the winter because no lives there til it warms up. I have another set down in the oil shed to power the biodiesel processor. Neither sets are going to be used till April ish. I have a permanent setup down in the valley camp where we stay in the winter. It seemed a waste to not bring all the panels down to the valley for the next few months.
It occured to me that the combined amperage of all the panels would possibly over whelm a single C60 and rather then shell out to get a bigger charge controller, perhaps I could just add a second C60 from one of the other systems.

So make sure about the set points.
DF

[birdhouse]

gotcha. 

would you bring the batteries down to the valley camp as well?  it wouldn't be ideal to let them sit without getting any charge for a long duration. 

adam

[DualFuel]

Hi,
The upper camp has an airx to charge the gelcel cell tower take outs that are up there. The wind never stops, which is why I am wintering down in the valley camp.
DF

[tecker]

Any charge controller will see the bank as float if hooked in parallel . Especially as the state of charge impedance rises. If you describe your equipment in detail you'll probably get some info you can count on.