Siemens SITRANS TH320 Operating Instructions Manual page 56

Connecting
6.5 Connecting TR420
2. Connect the supply voltage to the terminals 3 (+) and 4 (-).
For devices with HART communication, connect a ≥ 250 Ω resistor.
3. Take the polarity into account. The device has reverse polarity protection.
56
Input 1: TC (int. CJC or
ext. 2-wire or 3-wire CJC)
Input 2: 2-wire, 3-wire or 4-wire
RTD
Input 1 (I1) and/or
input 2 (I2):
3-wire or 4-wire potentiometer
SITRANS TH320/TH420/TR320/TR420 (mA/HART)
Operating Instructions, 03/2018, A5E41864807-AA
Input 1 (I1): 5-wire potentiome‐
ter
Input 2 (I2): 3-wire potentiome‐
ter