Yokogawa Button Operated MV2000 - Manual (Page 72)

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IM MV1000-17E
Using the Serial Interface
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Index
3.6 Usage Example of the Modbus Function
This section explains an example of setting two MV1000s that are connected via the
serial interface, one configured to be a Modbus master and another configured to be a
Modbus slave. This section refers to the MV1000 configured to be a Modbus master as
the MV1000 master and the MV1000 configured to be a Modbus slave as the MV1000
slave.
System Configuration and Operation
The measurement channels, computation channels, and communication input data
shown below will be used. We assume that the serial interface is already configured.
MV1000 slave
(Modbus slave)
Serial
communication
Reads measured data from the MV1000 and
displays data on a computation channel
(/M1 or /PM1 option).
MV1000 master
(Modbus master)
Measurement channel 1
Input range: –2.0000 to 2.0000 V
Computation channel 101
–2.0000 to 2.0000 V
Communication input data C01
Address: 1 Address: 2
Start the computation
Displayed in group 1
Measured data
Command
Operation
• The MV1000 master reads the measured value from the MV1000 slave channel 1 into
communication input channel C01 and displays the value on computation channel
101. The MV displays computation channel 101 in group 1.
• The measured value of MV1000 slave channel 1 is transferred to the MV1000 master
as an integer in the range of –20000 to 20000.
• The MV1000 master displays values in the range of –2.0000 to 2.0000 V for values
in the range of –20000 to 20000. The value is linearly scaled using the following
equation.
The value on MV1000 master computation channel 101 = Communication input data
C01 Ч 0.0001