Hart / 4-20 Ma Specifications; A.2 Hart / 4–20 Ma Specifications - Emerson Rosemount Reference Manual

Appendix A: Reference Data
April 2014
A.2 HART / 4–20 mA specifications
Power supply
External power supply is 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 are rated to 42.4 Vdc.
Wiring diagram
See Figure A-1 on page
Alarms
Custom factory configurations of alarm and saturation levels are available for valid values with
option code C1. These values can also be configured in the field using a field communicator.
Transient protection (option code T1)
The transient protector helps prevent damage to the transmitter from transients induced on the
loop wiring by lightning, welding, heavy electrical equipment, or switch gears. The transient
protection electronics are contained in an add-on assembly that attaches to the standard
transmitter terminal block. The external ground lug assembly (code G1) is included with the
Transient Protector. The transient protector has been tested per the following standard:



LCD display
Optional five-digit LCD display includes 0–100% bar graph. Digits are 0.4 inches (8 mm) high.
Display options include engineering units (°F, °C, °R, K, ohms, and millivolts), percent, and
milliamperes. The display can also be set to alternate between engineering units/milliamperes,
Sensor 1/Sensor 2, Sensor 1/Sensor 2/Differential Temperature, and Sensor 1/Sensor2/Average
Temperature. All display options, including the decimal point, may be reconfigured in the field
using a field communicator or AMS Device Manager.
Turn-on time
Specification performance is achieved less than six seconds after power is applied to the
transmitter when the damping value is set to 0 seconds.
Power supply effect
Less than ±0.005% of span per volt.
SIS safety transmitter failure values
IEC 61508 Safety Certified SIL 2 Claim Limit


(1) A 2% variation of the transmitter mA output is allowed before a safety trip. Trip values in the DCS or safety logic solver should be derated by
2%.
198
205.
IEEE C62.41-1991 (IEEE 587)/ Location Categories B3.
50 S Wave 8
6kV/3kA peak (1.2
6kV/0.5kA peak (100 kHz Ring Wave)
EFT, 4kVpeak, 2.5kHz, 5*50nS
Loop resistance added by protector: 22 ohms max.
Nominal clamping voltages: 90 V (common mode), 77 V (normal mode)

Safety accuracy: Span 100 °C: ±2%

Span 100 °C: ± 2 °C
Safety response time: 5 seconds
20 S Combination Wave)
(1)
of process variable span
Reference Manual
00809-0100-4021, Rev GC
Reference data