| Terminal | Function | Notes |
|---|---|---|
 |
Power supply ground | Can also be used for grounding the transmitter. There is also an external grounding terminal on the bottom of the transmitter enclosure. |
| 24 V - | Negative supply voltage | 15–30 V DC 1 or 24 V AC ±10 % 50/60 Hz |
| 24 V + | Positive supply voltage |
1 When used with the HMP7 probe,
the minimum required power supply input is 18 V DC.