I'm not an Electrical Engineer, however, let's see if my research has been successful.
From those that are talking about powering the OEM and AUX fridge fans via a sugar cube relay, I had to refresh my memory of a single pole single throw relay and what terminal connections are connected to which wires and what goes on inside the relay.
This is what I found. Maybe this will help others to also understand.
And, if I understand it all, then here is the original wiring to the OEM fan and the new wiring with a sugar cube SPST relay to the OEM and AUX fans. (Danfoss BD35/50F compressor fridge)
So, correct me if I'm wrong...
The circuit that used to power the OEM fan is now only powering/triggering the sugar cube relay, reducing the load on the fridge electronic unit.
The "+12 VDC" on the right side of the sugar cube relay is a new electrical source, not connected to the fridge's electronic unit, maybe connected to the 12 VDC line before the fridge, or even a seperate direct line from the battery (which would work - either?, or be better?).
Corrections?
What I don't know is which sugar cube relay will work.
I'm not an Electrical Engineer.
I can see that the fridge electronic unit will do 0.5 amps continously when the fan is activated, and I can add up the amps my OEM and AUX fan will use, however, the sugar cube characteristics I've looked up online just don't have any meaning for me.
Does anyone have a web link to a sugar cube relay, along with a way to mount or hold the sugar cube relay?
Or, can anyone give the characteristics of a sugar cube relay that will work and I can search for that either online, or at my local electronics supply store.