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CQM1-SRM21-V1 Master Unit for CQM1 PLCs
Section 4-4
Master Unit Components
The following diagram shows the main components of the CQM1-SRM21-V1
Master Unit. The functions of these components are described below.
Indicators
The following table shows the meaning of the indicators.
Indicators
Indicates the operating status of the Master Unit
and the status of communications with the Slaves.
DIP Switch
Alarm Output Terminals
These terminals are shorted when an error occurs.
Connect to a warning device.
Communications Terminals
Connect the Slaves' transmission cable to these
terminals.
Terminal block screws
These screws attach the terminal
block. The terminal block can be
removed when these screws are
loosened.
SRM21-V1
These pins have the following functions:
Pins 1 and 2: PLC word allocation setting
Pin 3: Number of points/unit number setting
Pin 4: Communications mode
Pins 5 to 6: Reserved (Always OFF.)
Indicator
Status
Meaning
RUN (green)
ON
The Unit is operating normally.
OFF
Indicates one of the following conditions:
The power is OFF, there is an I/O UNIT OVER error, or
there is an I/O Bus error.
SD (yellow)
ON
Data is being transmitted.
OFF
Data is not being transmitted.
RD (yellow)
ON
Data is being received.
OFF
Data is not being received.
ERC (red)
ON
A Slave has been withdrawn from communications.
(Communications error)
OFF
The Slaves are communicating normally.
ERS (red)
ON
The data areas between the Slaves overlaps when the
number of points/unit number setting is set to 4-point
mode.
Flashing
A node number is out-of-range, as follows:
(The Unit doesn’t check for node numbers 8 or higher.)
The PLC is allocated 2 words and the number of
points/unit number is set to 8-point mode, but the node
number is 2 to 7.
The PLC is allocated 4 words and the number of
points/unit number is set to 8-point mode, but the node
number is 4 to 7.
The PLC is allocated 2 words and the number of
points/unit number is set to 4-point mode, but the node
number is 4 to 7.
OFF
The data area and address settings are correct.