>During a tech counselor inspection, we discovered that my battery contactor
>felt pretty warm when its master switch was on (engine not running - don't
>have one yet). I later measured it at 135 F, regardless of load on the
>battery. After moving the battery to the other contactor, it also measured
>135 F after being on for about 10 minutes. (I have dual batteries,
>contactors, and master switches.) These contactors are Stancor 70-914, with
>nominal coil resistance of 16 ohms at 12 volts, rated at 80 amps continuous.
>Voltage measurements across the contactor coil, master switch, and wiring
>indicate there's about 0.8 amps flowing, which is about what I think it
>should be.
>
>So my questions are: 1) Has anybody else measured contactor temperature?
>and, 2) Should I be worried about this?
A battery contactor is a continuous duty rated device and as you
have observed, dwill draw about .8 amps at 14 v which translates
to something on the order of 10 watts. It is NORMAL for all devices
of this class to run warm. Starter contactors will draw about
4 amps or 50 WATTS which would make them toast in a vew minutes.
This is why they are INTERMITTANT rated devices.
Bob . . .
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