Modbus MFU Option Card Installation Manual
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Publication PUB091-003-00_0119
Command
IQ / IQT actuator SI / EH actuator
ROMpak / Q
actuator
Modbus over the network
Open
Close
Stop
Emergency Shut Down
Relay output DO-1
*
Relay output DO-2
*
Relay output DO-3
*
Relay output DO-4
*
Analogue Position Demand
Local Controls
Open
Close
Stop
Direct Hard Wired Inputs
Open
Close
Stop/Maintain
Emergency Shut Down
Open Interlock (active prevents opening)
Close Interlock (active prevents closing)
Note:
– Requires Extra Relay Indication board to be fitted
– Push to Run action only. Maintained action not available if analogue positioning is
used
The Modbus RS-485 network commands will operate the actuator provided -
Local/Local Stop/Remote selector is in ‘Remote’,
On IQ or IQT actuators, Modbus commands are not inhibited by the ‘Inhibit/DI-4’ input
parameter setting and DI-4 condition
No interlock is active on IQ or IQT actuators.
There is no standing hard wired control input active
No alarm condition prevents it from moving
Open
A digital command to cause the actuator to open to the fully open
position as indicated by the Open limit switch. Under correct operation
the actuator stops either when the open limit switch is reached, when
the torque exceeds the value set and the open limit switch has been
reached, or a new command is sent over the network.
Close
A digital command to cause the actuator to close to the fully closed
position as indicated by the Close limit switch. Under correct operation
the actuator stops either when the close limit switch is reached, when
