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Old 12-17-07, 07:17 PM   #4
GRM
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Join Date: Nov 2003
Location: West Coast Hometown: Morgan Hill, Ca
TLCA# 16721
Posts: 169
Quote:
Originally Posted by Fast Eddy View Post
You need to know how much current the relay is pulling. I=current. Then you want to drop V=1.4 volts. V=I*R and R=V/I. I'd guess it's probably around .25 amps, so you'd need about 6 ohms. The resistor needs to be rated for the power too. This is P=IV or about 3 watts.

Test, measure and adjust. You could get a rated potentiometer and just dial it down until you hear the relay click. I've got a variable power supply if you want to meet up over beers. My multimeter is currently on 'missing' status though.
I'll take you up on that! Biggest issue for me is trying to find a proper 11 volt system. Although, It may have to be after the new years, as I have too many projects on my plate to spend a day doing something like this.

What I am trying to do is to make my ARB Fridge kick off when the voltage in the battery hits 10.5 or 11 volts. This way I don't drain my 2nd battery to 1 volt, thus killing an odyssey battery.

Engel makes one of these controllers, Engel makes a controller like I describe, although I was told how to make one for $10 that was very effective.


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