ROBERT G. HOWARD wrote:
>
> These bulbs are rated 200 mA at 7.5 volts.
> _ If _ W = A * V, then W = 1.5A when .2A * 7.5V
> The 12v bulbs I removed had markings of 2.2 and 3.0 W.
> IF my formula for W = AV is correct, then there isn't much difference in
> current.
> Someone who knows electric theory is invited to participate in this.
> Electricity is not my first love, and I'm trying to perfect a hydraulic
> lightbulb to get away from the stuff entirely.
> Bob
Standard bulbs are marked 2.2W at 12v, this gives 183mA. But these other bulbs
are rated 200mA at 7.5v, so at a nominal 12v they will draw about 320mA i.e.
some
75% more current. Admittedly there may be some positive temperature
coefficient
effect that will tend to limit the current increase at higher voltages, but I
would still expect the end result to burn out the rheostat sooner.
PaulH.
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