One question about solar controllers

Hello! First post here...

I'm putting together a simple solar setup for powering irrigation to a garden and sprinklers. I have one little question about the hookup of the controller.

Basically, all of the simple solar controllers are designed the same: panels connect to the +/- terminals on the left, battery to the center, and the load to the right:



My question is regarding the load. I'm going to be using 3 separate 12v water pumps. Never at the same time. They will all be hooked up to a distributor block (a terminal block / busbar type system). Should I run the distribution block, and hence the 3 pumps all off of that 3rd terminal of the controller? Or should I leave that empty, and wire the distribution block from the battery directly?

All of the diagrams always show a light bulb or some other low powered device off of the "load" terminals. I wasn't sure if it was meant for a small load, or everything you're powering.

Thanks!

As long as the controller is rated to handle the load, then I'd connect to it instead of the battery.

Most (if not all) battery controllers are designed to disconnect the load if the battery voltage falls too low, this will keep your pumps from destroying your battery if it runs out of charge.

Note: the specs for the controller should tell you how many 'amps' of load it can handle.  If it doesn't then don't buy that controller (it's junk).  Make sure the rated load is higher than the rated load current on the pumps.
Note2:  Buying a controller with detailed specs doesn't mean that it's not junk, but if they can't be bothered to post specs then it's pretty much guaranteed to be junk.

Thanks. I didn't want to bog down my post with specs of the selected equipment, but yes, the controller is rated at about 4x the amp draw of the pumps.

Brandon Wallace wrote:the controller is rated at about 4x the amp draw of the pumps.

Just to be clear, Are you using the controller amp rating or the load amp rating? A 40A controller does not mean the "Load" circuit can handle 40A