Emerson Rosemount 2051, Справочное руководство

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Reference Manual
00809-0100-4107, Rev BA
Section 2: Configure
April 2013
Configuration
2.10 Configuring burst mode
Burst mode is compatible with the analog signal. Because the HART protocol features
simultaneous digital and analog data transmission, the analog value can drive other equipment
in the loop while the control system is receiving the digital information. Burst mode applies only
to the transmission of dynamic data (pressure and temperature in engineering units, pressure in
percent of range, Scaled Variable, and/or analog output), and does not affect the way other
transmitter data is accessed. However, when activated, bust mode can slow down
communication of non-dynamic data to the host by 50%.
Access to information other than dynamic transmitter data is obtained through the normal
poll/response method of HART communication. A Field Communicator, AMS Device Manager,
or the control system may request any of the information that is normally available while the
transmitter is in burst mode. Between each message sent by the transmitter, a short pause
allows the Field Communicator, AMS Device Manager, or a control system to initiate a request.
Choosing burst mode options in HART 5
Message content options:

PV only

Percent of Range

PV, 2V, 3V, 4V

Process Variables

Device Status
Choosing burst mode options in HART 7
Message content options:

PV only

Percent of Range

PV, 2V, 3V, 4V

Process Variables and Status

Process Variables

Device Status
Choosing a HART 7 Trigger Mode
When in HART 7 mode, the following trigger modes can be selected.

Continuous (same as HART5 burst mode)

Rising

Falling

Windowed

On Change