Thursday, October 15, 2015

Power Pointing, part two

Wherein we wire the house and car batteries together. The main question was how to get cable access to the car batteries.

Ford, in their wisdom, decided to store a ~6.7 million Joule energy source (AKA the pair of stock AGM batteries) under the driver's seat .

I had first thought to punch one hole low down in the seat base. But, the base is slanted (insert political joke here.), and the steel is very hard. I could not get a starter hole drilled.
I found that if I slightly widened one for the covered slots higher up, it would fit a cable and grommet.
So that's where the cables are routing.

I suspect those slot are there in case you have flooded batteries, and need some venting. They are covered inside the base with a plastic sheet.

I added lugs to the seat end of the cables, and roughly determined their placement in the seat base.
Then I fed the other end of the cabled in between the inner and outer side walls. I punched a hole in the inner wall and used a grommet.

Continued running the lines toward the back. When I neaten things up, I will be filling the holes in the rib shown below with expanding foam to keep the cables away from the metal edges.

I found a convenient hole to get back to the inside world.

Wired in the BlueSea ML-ACR relay. (That's the VSR in the last post's block diagram).

Attached the cables to Annie's batteries and neatened up a bit.

Put the seat base back together, and called it a day.

There are two reasons for this interface. One is to allow Annie's alternator to charge the house batteries as we drive. The other is in case Annie's batteries die. I can switch the ML-ACR on and use the house to jumpstart Annie.

I had planned on adding a fuse at Annie's batteries, in case something went awry between the two battery sets. However, the BlueSea instructions explicitly say not to do that if you want to run as a jumper. So, I am not going to do that yet. Also, since it's a real pain to access the under seat battery junctions, if I do add a fuse, it will probably be near the ML-ACR.

Finally, the ML-ACR has a remote control switch. I'm still deciding where I want to install that. It may go in the control/monitor panel that I'll be putting in above the fridge.