I prefer having a cold beer when I’m on our boat, but since this is usually on the sunny days, the performance of our fridge (Waeco CF-18) was too weak to cool one down in a short time (temperature in the cabin goes up to ~35° C if the sun is burning down).
I’ve been thinking about some kind of a GSM-based remote control, and actually found a nice product called microguard. The product seemed perfect, relatively cheap, easy to implement, available, but there was no time-out that could be set. Even if I have a separate starter-battery, it was key to find a solution that turns off the fridge after a given time without user interaction. Luckily, the guy who runs microguard was very cooperative, and added a timeout feature for me (and everyone else of course).
The module now turns on a relay for two hours after it’s been called from my or one of 4 other predefined phones. this is a bit on the short side, but I can live with calling twice.
This is how my installation looks:
From left to right:
Charge split diode / Rear side of main switches / Fridge fuse / Microguard module with relays, cables, mounted on an a plastic case / RedBull cup as holder for a Siemens S45.
The Cat5 network cabling goes directly to the voltmeters on the dash, this was made to show the exact voltage without loss due to load on the cabling.
As mentioned before, I have two separate batteries the starter is a traditional lead/acid battery, and the domestic is an AGM type, which allows deep cycles.
This is how the battery compartment looks:
The switches on the left are starter / jumper / domestic. This allows maximum flexibility. The domestic main switch actually doesn’t kill the microguard / fridge, so it can be off, and I can still call the fridge.