Emerson MSM400 manual Hart Smart Communications, Sensors

8.0 HART SMART Communications

The MSM400 is compatible with the HART digital signalling system, either as well as the 4-20 mA output , or on a Bus system. MSM400 supports Version 5.x of the HART protocol, and is fully supported by the MOBREY CK-1 HHC (Hand Held Communicator) and by the UNIVERSAL 275 HHC. It is normally necessary to load the Universal HHC with the transmitters Device Description to access anything more than the basic transmitter information-contact Mobrey Measurement for details. The MSM400 can also communicate with the MOBREY H-View PC based system.

Normal requirements of the loop impedance apply to allow the HHC to communicate properly. The MSM400 has a built in 270 ohm load, which can be selected if required-see section 4.6. This section also shows the special terminals in the MSM400 terminal compartment available for connection of a HHC across the current output. The MSM400 Cn number in relation to HART circuits is 1.

Please consult the HHC manual to see how to interrogate the Universal and Transmitter specific parameters.

The HART messages and Transmitter/Sensor ID Numbers are accessed and set up (where allowed) by the operator on the INFORMATION Structure, APPLICATION+CONTROL UNIT+SENSOR screens. Some of this data is factory preset, and is not alterable, to make the MSM400 identifiable to Universal communicators. But the main Description, Tag Number and Message should be used to identify the equipment and the actual site application for site operator use.

The Normal Universal Commands are always available over the HART interface---

PV-Process Value

% of current output (% of FSD)

Actual mA current output being transmitted Alarms active

Temperature (inside the electronics housing) PV for 0 or 4 mA output as programmed PV for 20 mA output as programmed

PV units of measurement

Time Damping used on the measurement Description (Customer supplied) Message (Customer supplied)

Tag Number (Customer supplied)

9.MAINTENANCE / INSPECTION

9.1Spares

The MSM400 is a factory built in instrument and apart from the mains fuse there are no spare parts that can be fitted in the field. Should the MSM400 require any repair or replacement parts, it must be returned to Mobrey Measurement for action.

CONTROL UNIT

No maintenance is required beyond occasional cleaning of the enclosure with a damp cloth. Solvents or bleaches should not be used. The fuse may only be replaced with the same type and rating. Do not modify or attempt to repair the unit.

SENSORS

No maintenance is required beyond occasional cleaning. The frequency of cleaning will be determined by experience. A message warning that cleaning is required may be generated when performing routine zero calibrations. Refer to Section 6.1

IP258

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