ProSoft inRAx MVI56-DEM, User Manual

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MVI56-DEM ♦ ControlLogix Platform Reference
Honeywell DE Communication Module
Page 40 of 80 ProSoft Technology, Inc.
March 6, 2008
ƒ The Shared RAM provides a mailbox through which the MVI processor and
the two DE processors can communicate. Access to this Shared RAM is
strictly controlled by the MVI56-DEM processor
ƒ The DEM module is connected to a Field Terminal Assembly (FTA), not
shown in diagram, which includes 250 ohm range resistors to convert the 4 to
20 ma current signals from the Smart Transmitters in the DE mode into 1 to 5
Volt signals
DE CPU
#1
68HC11
Receiver 1
Receiver 8
Write to DE
Instrument
Circuitry
Shared Ram
for data
exchange
Primary
DEM
controller
Allen -Bradley
Backplane
Transfer
circuitry
Read
C ommand
Write
Command
DE CPU
#2
68HC11
Receiver 9
Receiver 16
Write to DE
Instrument
Circuitry
To FTA
then to
instruments
Isolation
Barrier
The module supports both Single and/or Multi-variable Honeywell Transmitters
operating in DE. Supported Honeywell instruments include:
ƒ ST 3000 Smart Pressure Transmitter
ƒ STT 3000 Smart Temperature Transmitter
ƒ SMV 3000 Smart Multivariable Transmitter
ƒ MagneW 300 Smart Magnetic Flow meter
ƒ SCM 3000 Smart Coriolis Mass Flow meter
ƒ SGC 3000 Smart Gas Chromatograph
There can be Single and Multi-Variable instruments connected to the DEM
module, in any mix, totaling 16 logical DE Channels. An example configuration
could be as follows:
DE Channel Physical Type Instrument
1 SV ST 3000 Pressure
2 SV STT 3000 Temperature
3 MV PV 1 - SMV 3000
4 PV 2
5 PV 3
6 PV 4