DescriptionAccurate thermocouple temperature measurement requires a stable reference junction. It is common practice to create a transition reference junction by attaching a copper lead wire to each thermocouple leg. When the transition reference junction is held at the ice point 0°C (32°F) the output of the thermocouple appearing across the copper leads attached to the readout instrument is stable and predictable. For accuracy and convenience, OMEGA offers its series TRP REFERENCE PROBE which locates the thermocouple-copper transition reference junction at the end of an 1 /8 " diameter sheath for easy insertion into the TRCIII-A ice point calibration chamber. Up to six series TRP Probes can be used at one time in OMEGA’s Ice Point Chamber. Use the temperature-millivolt tables to convert readings into °C or °F when using a voltmeter with the TRCIII-A Ice Point reference cell shown below.