![Rosemount 3144 Скачать руководство пользователя страница 52](http://html1.mh-extra.com/html/rosemount/3144/3144_manual_1487449052.webp)
Rosemount Model 3144 and 3244MV Smart Temperature Transmitters
4-2
HARDWARE
DIAGNOSTICS
If you suspect a malfunction despite the absence of diagnostics
messages on the HART communicator display, follow the procedures
described in Table 4-1 to verify that transmitter hardware and process
connections are in good working order. Under each of four major
symptoms, specific suggestions are offered for solving problems. Always
deal with the most likely and easiest-to-check conditions first.
TABLE 4-1. Troubleshooting.
SYMPTON
POTENTIAL
SOURCE
CORRECTIVE ACTION
Transmitter
Does Not
Communicate
with HART
Communicator
Loop Wiring
• Check the revision level of the transmitter device
descriptors (DDs) stored in your communicator (see
Appendix B: Model 275 HART Communicator). The
communicator should report Dev v2, DD v1
(improved), or Dev v1, DD v3, v7, or v8 (previous).
Contact Rosemount Customer Central for assistance.
• Check for a minimum of 250 ohms resistance
between the power supply and HART communicator
connection.
• Check for adequate voltage to the transmitter. If a
HART communicator is connected and 250 ohms
resistance is properly in the loop, then the transmitter
requires a minimum of 12.0 V at the terminals to
operate (over entire 3.90 to 20.5 mA operating range),
and 17.5 V minimum to communicate digitally.
• Check for intermittent shorts, open circuits, and
multiple grounds.
High Output
Sensor Input
Failure or
Connection
• Connect a HART communicator and enter the
transmitter test mode to isolate a sensor failure.
• Check for a sensor open circuit.
• Check the process variable to see if it is out of
range.
Loop Wiring
• Check for dirty or defective terminals,
interconnecting pins, or receptacles.
Power Supply
• Check the output voltage of the power supply at the
transmitter terminals. It should be 12.0 to 42.4 V dc
(over entire 3.90 to 20.5 mA operating range).
Electronics Module
• Connect a HART communicator and enter the
transmitter test mode to isolate module failure.
• Connect a HART communicator and check the
sensor limits to ensure calibration adjustments are
within the sensor range.
Erratic Output
Loop wiring
• Check for adequate voltage to the transmitter. It
should be 12.0 to 42.4 V dc at the transmitter
terminals (over entire 3.90 to 20.5 mA operating
range).
• Check for intermittent shorts, open circuits, and
multiple grounds.
• Connect a HART communicator and enter the loop
test mode to generate signals of 4 mA, 20 mA, and
user-selected values.
Electronics Module
• Connect a HART communicator and enter the
transmitter test mode to isolate module failure.