MITSUBISHI ELECTRIC QJ71C24N - Manual (Page 106)

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MELSEC-Q
4 SETTINGS AND PROCEDURES PRIOR TO OPERATION
4.7 Individual Station Test
After installing the Q series C24 to the base unit of QCPU, perform an individual station
test first to check the switch setting (see Section 4.5.2) and operation of the Q series
C24.
POINT
(1) When a problem occurs during data communication with an external device,
perform an individual station test as described in this section to check whether
or not there is any problem in the operation of the Q series C24.
(2) In order to avoid problems, set the PLC CPU to STOP status during the
individual station test.
(3) Test both interfaces of the Q series C24 simultaneously in an individual station test.
Alternatively, either one of the interfaces can be tested in an individual station
loopback test.
In that case, ignore the test results on the interface side for which the test is not
performed.
(4) Cable removal and reconnection before and after the individual station
loopback test should be performed with the power to the Q series C24
mounting station turned off.
(5) To restart data communication with an external device after an individual
station test, check the specifications of the devices used before defining
various settings and reconnecting cables.
For the interface that is not used for communication (no cable connection), define
the switch settings in GX Developer as follows (for the setting method, see Section
4.5.2).
• Communication protocol setting: 0 H to 7 H
• Transmission control settings and communication rate settings: all set to OFF.
(6) If an error occurs even though the correct settings have been made for the Q
series C24 through an individual station test, please consult your nearest
dealer or branch office with a description of the error.
4.7.1 ROM/RAM/switch tests
A ROM/RAM/switch test checks the contents of the memory of the Q series C24 and
the switch settings set with GX Developer.
Perform a ROM/RAM/switch test with the procedure described below.
(Procedure 1) Communication protocol setting and transmission setting (see Section 4.5.2)
(1) Set the communication protocol setting on the CH2 side to E
H
(ROM/RAM/switch test).
Set the communication protocol setting on the CH1 side to the number (1 to 8)
used for data communication with an external device following the test.
(2) Set the transmission settings for the two interfaces to match the specifications
used when communicating data with an external device.
(Procedure 2) Performing ROM/RAM/switch tests
(1) Set the PLC CPU to STOP status.