Wire And Apply Power - Emerson Rosemount 644R Quick Start Manual

Quick Start Guide

5.0 Wire and apply power

5.1 Wire the transmitter
Wiring diagrams are located inside the terminal block cover.
Figure 4. Sensor Connections Diagram
1234 1234
2-wire
3-wire RTD
RTD and V
and V
1. The transmitters must be configured for at least a 3-wire RTD in order to recognize an RTD with a
compensation loop.
2. Rosemount Inc. provides 4-wire sensors for all single element RTDs. Use these RTDs in 3-wire
configurations by leaving the unneeded leads disconnected and insulated with electrical tape.
5.2 Power the transmitter
1. An external power supply is required to operate the transmitter.
2. Remove the terminal block cover (if applicable).
3. Connect the positive power lead to the "+" terminal. Connect the negative
power lead to the "–" terminal.
4. Tighten the terminal screws. When tightening the sensor and power wires, the
max torque is 6 in-lbs (0.7 N-m).
5. Reattach and tighten the cover (if applicable).
6. Apply power (12–42 Vdc).
Rosemount 644H
A
B
A. Sensor terminals
B. Communication terminals
C. Power/configuration terminals
5.3 Load limitation
The power required across the transmitter power terminals is 12 to 42.4 Vdc (the
power terminals are rated to 42.4 Vdc). To prevent damaging the transmitter, do
not allow terminal voltage to drop below 12.0 Vdc when changing the
configuration parameters.
12
1234
4-wire RTD
and V
(2)
1 2 3 4
C
1234
T/C
(1)
and mV
Rosemount 644R
A
Max torque is
6 in-lb. (0/7 N-m)
C
June 2016