4-20 Ma/Hart Specifications; A.5.4 4–20 Ma/Hart Specifications - Emerson Rosemount 644 Reference Manual

Reference Manual
00809-0200-4728, Rev RA
Sensor connections
Rosemount 644 Sensor connections diagram
1 2 3 4
RTD and
* Rosemount Inc. provides 4-wire sensors for all single element RTDs.
You can use these RTDs in 3-wire configurations by leaving the
unneeded leads disconnected and insulated with electrical tape.
Tagging
Hardware
13 characters total

Tags are adhesive labels affixed to the side of the transmitter

Permanently attached to transmitter

Character height is

Software
The transmitter can store up to 8 characters for the HART protocol

Order software tag with C1 option code

A.5.4 4–20 mA/HART specifications
Power supply
External power supply required. Transmitters operate on 12.0 to 42.4 Vdc transmitter terminal
voltage (with 250 ohm load, 18.1 Vdc power supply voltage is required). Transmitter power
terminals rated to 42.4 Vdc.
Load limitations
Maximum load = 40.8 X (supply voltage - 12.0)
1240
1100
1000
(1) Without transient protection (optional).
Note
HART communication requires a loop resistance between 250 and 1100 ohms. Do not
communicate with the transmitter when power is below 12 Vdc at the transmitter terminals.
Specifications and Reference Data
1 2 3 4
4-wire RTD
2-wire 3-wire RTD
*
and
1 / -in (1.6 mm)
16
4–20 mA dc
750
500
250
0
10 18.1 30
12.0 Min
Supply Voltage (Vdc)
Appendix A: Specifications and Reference Data
1 2 3 4 1 2 3 4
T/C
and
and mV
(1)
HART and Analog
Operating Range
Analog Only
Operating Range
42.4
April 2015
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