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Old 11-22-2006, 05:55 PM   #118
Slab Sucks!
harderkev's Avatar
Joined: Jun 2005
Location: Santa Margarita, Ca.
Oddometer: 356
Progress Report

I have my jacket completely wired now. As I posted earlier, I tailored the mesh liner to fit snug against my body while allowing the outer shell to keep a loose appearance. I threaded the 30ga. wire between the outer shell and mesh liner, only poking through the liner every few inches to keep the wire in place. The small amount of wire poking through the liner does not burn my bare arms while wearing only a short sleeve shirt.

In my first attempt, I tried to wire the entire jacket with 34' of wire. I ran out of wire just before I finished my wiring pattern, so I had to add a few feet to the length. I plugged-in the PWM and checked the heat level. I was running about 48 watts in this configuration and I could tell just standing beside the bike that it wouldn't be enough.

I decided I would rewire the jacket with two 30' lengths of the 30ga. wire, each covering half the jacket, and wired in parallel. I removed the first wiring job and installed the two 30' lengths. The biggest PITA is finding a wiring pattern that uses all the wire you want without running out before you end your pattern! I had to pull some wiring a couple of times to get it right.

Final outcome is the jacket has 1.7 ohms resistance, draws 8.5 amps and cranks out a whopping 122 watts at 14.4 volts!! I wasn't afraid of having too much heat since the PWM worked very well on my test run and will turn down to zero output. For comparison, the Warm N Safe men's jacket has 1.6 ohms resistance and would draw 9 smps and put out 130 watts at 14.4 volts.

The PWM sits in a project box in my tank bag and can be reached easily by unzipping the bag zipper just a few inches.

I'll be wiring a pair of pants as soon as they arrive (I altered the first pair in a way I don't like and can't undo). I'm planning to put two 40' sections in the pants to match the heat output of the jacket (I figure around 90 watts total).

Here are my supplies:
Hook Up Wire
MX033 Pulse Width Modulator
Project Box
SAE flat connectors

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