PANEL TEMPERATURE METER -30 TO +70 C - ADAFRUIT 576

Put a temperature meter anywhere with this very handy display. This panel meter displays the temperature of the attached waterproof 1% thermistor in °C. It does require a DC voltage to run, at 4.5-30VDC. It has reverse polarity protection in case you swap the power leads by accident. 

To use, simply connect the thin red wire to a positive supply, and the thin black wire to ground. Then tape the black thermistor bulb to whatever you want to measure - or leave it loose to measure ambient temperature. The display has a microcontroller that will read thermistor resistance and display the corresponding temperature from -30°C to 70°C with 1 °C precision on a 3-digit 0.56" tall 7-segment display. The meter draws 3-4mA to power the microcontroller and display. This particular LED display is a nice vivid blue, which we found very readable. To mount to your enclosure, simply cut a 45.5mm × 26.5mm rectangle and snap it in. 

This meter can only display the temperature in Centigrade °C, it cannot be modified to °F and we do not have a version that is °F.