In a message dated 98-12-20 07:45:24 EST, you write:
> Please feel free to jump all over me if I am wrong, but wasn't there a
> discussion of this some time ago where some one pointed out that the
voltage
> stabilizer is not a regulator in the conventional sense. Since the meters
> connected to it are using bimetal strips inside, it adjusts the voltage and
> compensates for temperature differences. i.e. in colder weather the
voltage
> will be higher so a half a tank still reads a half a tank.
Jim,
You are correct. In cold weather, the bi-metal strips in the meters won't bend
as much with the same sender resistance as they will when warm, so a higher
voltage is required to compensate. The bi-metal strip in the stabilizer also
doesn't bend as much when cold, so for the same current, it opens later than
when warm, and cools off to close quicker. As a result, the On time is longer
compared to the OFF time, so the average voltage is higher-just what the
instruments need to compensate for the cold.
The temperature compensation in a typical solid state circuit provides the
wrong type of compensation - the output voltage stays constant with a change
in temperature. How significant the difference is, I don't know.
Anyway, if you want to build a solid state stabilizer, the current draw for
the gauges is quite small, less than 1/2 amp each. I have the exact figures
somewhere, but I can't find them right now.
Dan Masters,
Alcoa, TN
'71 TR6---------3000mile/year driver, fully restored
'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
http://www.sky.net/~boballen/mg/Masters/index.html
'74 MGBGT---3000mile/year driver, original condition - slated for a V8 soon
'68 MGBGT---organ donor for the '74
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