At 03:48 PM 7/18/00 +0200, you wrote:
>Hello everyone..
>
>I am looking for something surprisingly hard to find: a temperature switch
>operating in the 3 deg C range. i.e. a straight on/off thermostat that need
>not be adjustable (but could be). The load being switched draws 1 mA or so
>at 220 V (a relay coil).  Has someone seen what I'm looking for?

Sounds like you just need a thermostat. There is a type that looks a bit
like a TO-3 transistor case, but with a couple of spade (Faston) connectors
on
the 'bottom'. They are surprisingly accurate and cheap (at least in large
quantities, cheaper than semiconductor solutions by far since they include
both a sensor and a power switching device and require no power supply).

The main limitation is that the differential (hysteresis) between on and off
temperatures has to be fairly large (several degrees C, IIRC).

Try an appropriate directory for your location, these are more appliance
parts than electronics items.

Best regards,
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