Answer / carl_ellis

1) How do you know that the device talks HART? Many field transmitters talk Brain, Honeywell DE, Foundation Fieldbus, Profibus or 4-20mA only.

Have you confirmed the HART functionality on that device?

2) Point-to-point (communicator-to-transmitter) is usually done with the device at address 0 and with the communicator polling address 0.
Is the communicator polling address 0?
Is the device at address 0?

3) On many transmitters, HART can be disabled. Is HART enabled on this transmitter?

4) The transmitter has to be powered, initialized and in its operating mode in order to communicate via HART. Sometimes transmitters are not powered, but when connecting from the a marshalling panel, it is obvious, because the transmitter is remote location. Is the transmitter powered and operating?

5) Are connections across the dropping resistor or across the transmitter's (+) or (-) terminals? Connecting across a pressure transmitter's 'test' terminals will not work properly for HART communication.

6) A loop isolator module that is not specifically designed for HART will strip off the HART signal, but pass the 4-20mA current signal. If a loop isolator is installed in the loop, is it designed for HART operation.

7) If the power supply ripple and noise exceeds the HART specification, the power supply noise will interfere with HART or prevent communication entirely.

8) The 475 can have 3 terminals at the top where the banana plug field cable plugs in. 2 terminals are for HART, 2 terminals are for Foundation Fieldbus (FF). If the cable is plugged into the 2 terminals for FF, HART communications will be blocked by not having a cable in the correct port.

Carl Ellis
Measure First

In oil & gas industries and petrochemical industries, there are classification of zones like zone 0, zone 1, zone 2. Is there any differences in voltages or power supply supplied for the process instruments, control instruments depending on the zones

1 Answers  

---

What is the difference between mmwc and mmwg?

0 Answers  

---

please tell me five types of fault of control valve and positioners?please

1 Answers  

---

What is CNC

1 Answers  

---

How can i test procedure grounding for CAT-7 cable? Or How can we test procedure CAT-7 Cable Electrically safe?

0 Answers   Tecnimont,

---

what is sequence table in DCS . make a logic in sequence table for tripping of ID fan in Boiler(in YOKOGAWA CS 3000 DCS).

1 Answers   Yokogawa,

---

what is difference between RTD , thermo couple and thermistor in general ?? (except temperature co-efficient )

5 Answers   Bilt,

---

what is loop1 and loop2 in MTS LT?

0 Answers   SPGC,

---

where can we use viberation transmitter,and how can we control viberation?

1 Answers   Maden,

---

WHAT ARE THE INSTRUMENTAL DIAGRAMSOF VALVES?

0 Answers   Artikal, ITC Infotech,

---

Why the tapping connections are taking above for gas service and below for liquid service?

2 Answers   ADCO,

---

what is insdustrial vibration.who it works. give atleast 2 types of insdustrial vibration

0 Answers  

---