Guys, i need to know if anyone can point me in the right direction.
I have solar, hybrid inverter and batteries. Now i want the batteries to only power light and medium loads not exceeding 500WH. Solar would power loads it can based on generated power. I have a 3.52KW setup so worst case scenario, i would be getting at least 600/700W which would suffice for minimal loads.
Now, assuming the PVs were generating 2KW earlier which would then be powering all loads, once this reduces to a low/medium level due to rain or time of day, heavy loads should be turned off to prevent battery complementing the insufficient PV energy. If PV energy rises again, then the heavy loads would be turned back on. By turning on and off, i meant toggling the breaker/switch that controls those devices
You are looking to build a diy solar diverter. I.e. When I have surplus power turn this (or these) devices on…
You will need several components.
A power monitor (IoTaWatt)
Contactors to activate the load
Programmable relays to trigger the contactors to open or close
Software to run the ‘rules’ that you define.
Shelly devices will work well for the relays, contactors are generic (if it is a heavy load you won’t run it directly through the Shelly but use the Shelly relay to trigger the contactors.)
The software side may be a bit of a mash up of home assistant, node red and others.
It isn’t going to be easy, but can be done.
Way beyond my competence but web search on diy solar diverters may give you some pointers.
I’m probably a bit late to this but here is my DIY Solar diverter design. Its primarily designed for Hot Water System (HWS) diversion but it should have sufficient capacity to switch the load you are discussing.
It can use Iotawatt or a Shelly device as the the input source. It includes schematics as well as some basic 3D printed enclosure details.