
An increasing temperature warning device for protecting an item from high temperature or fire damage comprising a thyristor connected in parallel with a reference voltage source. An audible or visual warning means is connected in series with the thyristor. When the temperature of the thyristor exceeds a specified temperature, the thyristor switches on and the warning means is activated. A series combination of a diode and a resistor can be connected in parallel with the gate of the thyristor to ...











