Introduction
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INTRODUCTION
The Rotork Modbus Module Actuator Field Control option card (MFU) uses 2-wire (half duplex) RS-
485 and the Modbus RTU protocol to allow for information exchange and control over the data
highway between the actuator and a suitable host system with a Modbus capability.
The module is an integral part of the actuator in which it is housed and is fitted within the main
electrical housing. For the IQ3, CVA and K-Range products, this electrical housing is double-sealed
and need not be opened once the actuator leaves the assembly plant. The CMA range of actuators
does not have double sealing and the electrical cover is required to be opened for connecting to Field
connections.
All adjustments to the settings for the module may be made via the Modbus data highway using a
Modbus master tool or via the Infra-red or Bluetooth actuator setting tools for those products that
support those interfaces.
The settings which must be correct for communication are: address, baud rate, parity and stop bits.
These are described in Section 6. The default values are: address 247, baud rate 9600, parity None
and stop bits 1.
The Modbus Module circuits do not impinge on the actuator control electronics; the actuator itself
remaining fully self-protecting. The module performs the tasks of network interface, actuator data
collection and the issuing of actuator commands.
The Modbus Module may command the actuator into which it is fitted to: open, stop, close, perform an
ESD operation, perform a partial stroke test (IQ3 only) or move to a set position. Commands to the
module come from the network and will have been generated in a master controller. The module
operates as a slave in Master/Slave communication mode only, using the Modbus RTU protocol.
Fig 1:
The Modbus Module Option Card Actuator Compatibility
IQ3
CVA
K-Range
CMA
SI3
