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Wiring of powerbox underway

April 25, 2020 — BarryK

I have started the internal wiring of the lithium powerbox, and this post is a progress report. Here is the previous post for this project:

https://bkhome.org/news/202004/powerbox-external-assembled.html

It is progressing slowly, but surely. I had to pause for awhile to think about some construction details. Anyway, here is a photo showing the wiring so far:

img1

...notice that the box is now painted black! I used a cheap "flat black" enamel paint spray can.

A change from the previous photo (see above link) is that I removed the Anderson plugs from the DC-DC charger and cut a round hole for the cables to go into the box. Next to the round hole is "half" of an Anderson plug -- this is for the wiring to the vehicle ignition key.

The wiring-board is propped alongside the box, for the photo. Top-left of the wiring-board is the shunt for the coulometer, the two black and red cables sticking out the top will go to the battery.

The "+bus" and "-bus" busbars were purchased from Jaycar:

https://www.jaycar.com.au/machined-brass-busbar-8-way/p/SZ2003

The terminal blocks at top-right are for wiring to the DC-DC charger. I purchased porcelain blocks:

https://www.jaycar.com.au/3-wire-porcelain-terminal-block-30-amp/p/HM3185

...however, afterward I noticed these, which would probably do the job:

https://www.jaycar.com.au/60-amp-12-way-screw-terminal-strip/p/HM3204

The blank space on the wiring-board is where the fuse holders will mount. This is where I had some problems, as the blade fuse holders in local shops, of the surface-mount terminal-block type, seemed too "light" to handle 20-30 amperes. The engine-bay is a more extreme environment, but this Redarc video does show the potential for catastrophic failure when using blade fuses:

https://www.youtube.com/watch?v=kZ76NsvvBE0

Snapshot from the video, of a melted inline blade fuse holder and fuse:

img2

I intend to post soon about what fuse holders I chose, and what got rejected. 

Tags: nomad