Modbus MFU Option Card Installation Manual
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Publication PUB091-004-00_0918
Partial Stroke Test
Moving a little-used valve by a small percentage from an end limit and
then returning it, proving that it will operate when required. Safety
related.
RS-485
The electrical properties of the data highway as defined by the IEC
8482 standard, copper conductors, 2-wire twisted pair.
Segment
A section of an RS-485 fieldbus that is terminated at each end in its
characteristic impedance. Each Segment can include up to 32 devices
with unitary load.
Abbreviations:
ACTCON
Actuator Control (Register).
CMA
Compact Modulating Actuator.
Comms
Communications.
CRC
Cyclic Redundancy Check (error detection).
CVA
Control Valve Actuator.
CVL
Linear version of CVA.
CVQ
Quarter-turn version of CVA.
DIO 1
Digital Input / Output Board, type 1.
DIO 2
Digital Input / Output Board, type 2.
DV
Desired Value.
ESD
Emergency Shut Down.
IEC
International Electrotechnical Commission.
MFU
Modbus Field Unit.
MV
Measured Value.
PCB
Printed Circuit Board.
PLC
Programmable Logic Controller.
RAM
Random Access Memory.
RIRO 1
Remote Input / Remote Output Board, Type 1.
RIRO 2
Remote Input / Remote Output Board, Type 2.
ROM
Read Only Memory.
RTU
Remote Terminal Unit.
SW
Software.
UPS
Uninterruptible Power Supply (CVA only).