Friday, November 28, 2008

Misc Friday

Ahh, Black Friday. A day when every red-blooded American's thoughts turn to... electric conversions. Today was a day for some miscellaneous things I've been putting off for a while. First, I actually installed the "extra" battery mount (one of the first parts I welded). There are three 3/8-16 RivNuts inserted, and three 3/16" by 2" bolts through the rack into the RivNuts. The rack is held level above the sheet metal by three 1" spacers (this was required due to the slope of the fender right next to the mounting point). I also used RivNuts as the top hold-down attachment point:


Next, I made a top for the "extra" battery from polypropylene. Because this battery does not have a rack-style enclosure, I decided to get a little fancy and create a lip around the top to prevent curious fingers from accidentally contacting 312 volts. Basically, I just cut half-way through the box along the edges, and then liberally applied heat with a heat gun. And then, with sufficient force, the edges were bent down:


Next, I reinstalled the heater blower. First, though, I identified the main wire that is hot when the blower is active - it's the light blue wire here. I then added a pigtail blue wire on this so that I can control a relay which gates the heater contactor - I only want the 2000W heater running when there is air flowing:


With some help from KatC, I installed the blower assembly. Here is the view from the engine compartment. The two gold braided wires on the right are the main wires for the heater core. The purple and black lines are the vacuum lines which provide vacuum for the flapper box (TBD - how to hook them up....) And the blue wire is attached to the pigtail I just made:


Finally, I spent some time actually going over the factory service manual wiring diagrams in some detail. This allowed me to determine that some more of the factory harness can go (and should go - it just clutters things up). On the passenger's side, this harness goes to the EGR solenoid, the fuel pump relay, and the "B+" relay (basically, a relay controlling a time delay shutdown circuit). None of those are needed for ElectroJeep, so this whole harness gets guillotined:


On the driver's side, this whole harness which emerged from the bulkhead was entirely dedicated to controlling the gas motor. So, it got chopped. Here you can see the final electrical tape wrapping - basically, each wire gets folded back on itself about 3/4", individually wrapped with electrical tape, and then the whole mess gets taped together:


Tomorrow - weather permitting - I'll reinstall the front rack, finish its holddowns, and start working on battery interconnects (!).

3 comments:

David Cunniff said...

Have you considered installing a thermal fuse in the heater power circuit? That way, it will shut off safely in the event of an over-temp situation, regardless of the power relay state. Cheap insurance...

David Cunniff said...

Follow-up -- of course you'll have to put the fuse close to where it will heat up quickly if things get out of hand with your 2000W heaters...

Ross Cunniff said...

Hmm... a thermal fuse is a good idea. Unfortunately, I've already installed the blower and I'm too lazy to take it out again :-) - maybe a thermostat? I'll do some research.