The model 621-0025R Resistance Temperature Detector Module (RTDM) is an input device that can read resistance sent from RTD probes. As the module reads the signals, an analog-to-digital converter within the RTDM changes the signals into binary counts. A Control
Processor Module can then read the counts and determine how to control the process that the probe is monitoring.

The RTDM is typically used in process and batch process applications that require precise temperature measurements for long periods of time. Reactors and ovens are examples of devices that the RTDM can monitor. The range of temperatures that the RTDM can
measure is -300 to 900 degF (-184 to 482 degC).

CAUTION

You may remove the 621-0025R from, or insert it into, a serial I/O card file while the system is powered, provided you use a 621-9938R Serial I/O Module (SIOM). DO NOT DO THIS with a parallel I/O card file, or a serial I/O card file containing a 621-9938 or 621-9940 SIOM.