Wiring in My 12 Refridgerator

[Rob in MT]

Just go my dometic cf-50, slick.

I'm going to be putting it in the cab of the truck. The camper has the aux battery, and the wiring is in place from the battery to the cab.

Can I cut the 12v plug (which has an 8A 32v fuse built in) off the end of the 12v wire, hook up the positive and negative, and then put the same size fuse in the end I will hook up to the battery? Or is it best to leave the plug, wire in a 12v outlet, and not put a fuse on the battery end?

Thanks for your help.

 

[dsrtrat]

When I mounted my Engel in the truck cab I added two 12 volt outlets. You want to be able to easily disconnect the fridge when not in use as some of them have a slight current draw even when switched off. If you leave the Engel connected the camper battery will be drained. I used Marinco heavy duty 12 outlets. The second outlet is nice to charge electronic equipment off the camper batttery which in my case is under the hood. You want to fuse the wire going from your aux battery to the cab. Put the fuse as close to the battery as possible and keep the fuse in the plug as well. Not fusing this wire can result in a fire if you have a short.
Dsrtrat

 

[UglyScout]

I went with Anderson powerpole style connectors for mine - zero chance for failure.

Either way ditch the stock plug and get a quality locking/self securing plug.

 

[K7MDL]

A fuse is used to protect the weakest link. As a general rule you want fuses close to the source of power, and you size them to protect the *wire* in case it gets damaged.

The wire should larger or equal to what the load requires. That means for only one load on your power wire you can use the smallest fuse to achieve protection of both the load and wire.

If you have a large wire with a large source fuse, and your load (the fridge) has a smaller wire or smaller load fuse specified (requires a smaller fuse to protect the motor for example) then you would use a fuse on the load's own wire, which is often also smaller size. Again the same rule applies, the fuse is sized to protect the smallest wire/load downstream from the source (or tee/connector, distribution block).

So if you have a heavy wire with big fuse from your aux battery, and you plug in a smaller wire with a load with a smaller fuse specified, you need to keep that smaller fuse in line very close to where you connect to the big power distribution wire. Each fuse protects its part. As mentioned, using a connector is a good idea to tap power off your large distribution wiring.

If your aux battery is located in the camper, you might have an isolation relay there also if you are charging from the truck. I locate my isolation relay under my truck seat so that camper power runs my toys in my truck cab when the engine is off. This requires no extra wire runs. Plus I can manually control the relay easily with my particular setup.

I happen to use Anderson PowerPoles also. Easy to use, inexpensive relatively, and reliable, high current, come in a couple sizes. You can get either solder terminals, or crimp type. The crimp type require care to not deform them or you will not get a reliable contact. Buy a bag of them, they are easy once you understand them.

- Mike