Wiring; Overview; Measurement Unit Connection; Sensors - Endress+Hauser TMT122 Operating Instructions Manual

4 Wiring

Wiring overview
Measurement unit
connection
"
!
!
12
4 Wiring
4.1

Overview

Terminal layout
fig. 5: DIN rail transmitter wiring
4.2

Measurement unit connection

Caution!
Switch off power supply before opening housing cover of the temperature sensor. Do not install or
connect the unit to power supply before the sensor is connected to the transmitter. If this is not fol-
lowed, parts of the electronic circuit will be damaged.
4.2.1

Sensors

Connect the sensor cables to the respective DIN rail transmitter terminals (Terminals
3 to 6) by following the wiring diagram (see fig. 5). Wiring plugs are removable for easy access.
4.2.2

Output signal and power supply

Connect the cable wires from the power supply to terminal 1 and 2 according to the wiring diagram
(see fig. 5). For convenient installation, the connection is designed as a removable plug, so the con-
nection can be made on the terminals, then plug in the connection socket to the transmitter hou-
sing.
Note!
The screws on the terminals must be screwed in tightly.
®
4.2.3 HART connection
Connection is made directly at the communication socket 7 and 8 at the front wall of the transmit-
ter. The sockets are inside the loop to a power supply or barrier. In order to connect the transmitter
in a hazardous area, please read the separate Ex documentation.
The measurement circuit must have a load of at least 250 Ω. If using the E+H power
Note!
supplies RNS 221 and RN 221N, this resistance is already installed in the unit and is therefore not
required externally (see fig. 6, and see fig. 7)!
Temperature DIN rail transmitter
Endress+Hauser