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Old 11-29-2009, 01:56 PM   #8 (permalink)
bwilson4web
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Quote:
Originally Posted by orange4boy View Post
. . .
If I knew more about electronics, I would probably agree with that approach. I will look into a current regulator and see if it's something I can handle. I was hoping for a simpler approach but I suppose I should start the new thread to describe what I hope to do.
Please never let my suggestions be anything other than that ... there is more than one way to 'skin that cat.' <GRINS>

The "Toyota Prius Electrical Wiring Diagram, 2003 Model" is publication EWD893U would be an excellent guide. Looking on pp. 50 and pp. 59, it looks like the main inverter 12 VDC supply and sense lines are:
  • C5 connector, pin 1 - main supply, WHITE
  • C4 connector, pin 3 - sense or secondary 5A line from aux B+ terminal, BLACK with RED STRIPE
  • C4 connector, pin 1 - IGCT unknown, WHITE with GREEN stripe to all ECUs
  • C4 connector, pin 2 - IDH unknown, YELLOW to A/C amplifier
Understand you are in new territory and I tend to be a conservative engineer. So I would probably do a lot of checking before trying to substitute a nominal 12.x VDC battery for the 13.8 VDC generated by the inverter. One wild thought, a 24 VDC deep discharge battery could be stepped down using a switching power supply to just about any lower voltage fairly easily and efficiently.

Bob Wilson
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