Wiring the solar charger controller questions

[wandererr]

I am finally getting ready to install the solar panels and the controller but I'm a bit confused as to how to wire it.

It has three segments
1. Panel
2. Battery
3. Devices

1. Panel is self explanatory - it will go to the panels
2. Battery to batter for the charger
3. Devices - probably won't use it as I doubt it can support my current draw:
- gas fridge controller voltage
- small devices chargers
- internal led lights
- rooftop fans
- small usb powered swamp cooler


Questions are as follows:
I have shore power charger and that goes to the battery. Anyone can think of any issues of backfiring the controller when on shore power?

also my agm battery has two sets of ports. Should I have my devices feed of the smaller posts and all the chargers be connected to the bigger posts?

The controller

https://www.amazon.com/dp/B01HDAXU7Y

 

[luthj]

No worries with multiple charge sources. Just make sure they are all set to match your batteries charge voltage specs. Beware cheap solar controllers. Most will undercharge out of the box and kill a battery early. If the voltage doesn't match the batteries specs, and can't be adjusted... Buy another model. Some models won't hold the absorb voltage long enough. Often 3+ hours at the absorb setpoint is necessary.

I would attach everything to the same two connections on your battery. But you can use either set if you prefer. Fuse everything as close to the battery as possible for main feeds. Branches need sub-fuses for their specific wire gauge.

 

[DLTooley]

Reducing all loads to the minimum during absorb is a good practice to maximize charge. The Victron 75/15 MPPT uses the batteries current acceptance rate to end the absorb phase so it's based on actual, not estimated, need. This is all the more important if your usage varies widely. The Victron has load terminals that will accept up to 15 amps (12v), and it records that usage displaying both charge and load on a bluetooth connection to a smart phone. You will be able to see what is actually going on. $120.