50S & 50D Thermometer
Calibration Information
position until the display is locked in self-test (all LCD segments on). This thermometer is now in the Reference Junction Sensor calibration mode. Shorting out the VIEW switch grid turns off a filter so that the reading stabilizes immediately.
13.Using the 80T-150U and the Fluke 87 Series IV Digital Multimeter (DMM), measure the reference junction transistor temperature by placing the 80T-150U probe tip against Q1, located in the middle hole of the isothermal block. Wait for the temperature reading to stabilize.
14.Adjust R16 for a temperature reading that is the same as displayed on the DMM.
15.Turn the thermometer OFF by shorting the ON/OFF switch grid, and reattach the top-case.
50S or 50D
Thermometer +
_
Copper wire
5520A
zf07f.eps
Figure 5. Calibration Connections
