Diagnostic Function - Mitsubishi Electric MELSEC Q Series Reference Manual

3 SPECIFICATIONS
Item
Self-loopback test
Internal self-loopback test
Hardware test
Forward loop/reverse loop
test
Item
Loop test
Setup confirmation test
Station order check test
Communication test
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(8) Diagnostic function

The diagnostic function is used to check the network's line status and the module
setting status.
The diagnostic function consists mainly of following two types of tests:
• Offline tests
• Online tests
POINT
Execute the online tests when the network module is communicating (T.PASS LED
is on). An error occurs if any of the online tests is executed from a station that has
been disconnected from the data link.
1) Offline tests
The network module's hardware and the data link cable wiring can be
checked at the system startup by setting the network module or GX
Developer to the test mode.
Description
Checks hardware including the send/receive circuits and the
cables of the transmission system of an individual network
module.
Checks hardware including the send/receive circuits of the
transmission system of an individual network module.
Checks hardware inside the network module.
Checks the wiring status of the forward and reverse loops in
the status in which all the stations are connected. (Remote
master station only)
2) Online tests
The status of a line and other items can be easily checked with GX
Developer.
If an error occurs while the system is in operation, the diagnostics
listed below can be executed while remaining in the online status.
Description
Checks the line status.
Checks for duplicate control stations
and station numbers.
Checks the order of stations connected
in the directions of the forward and
reverse loop.
Checks whether or not the transient
transmission can be performed
normally.
It also checks the routing parameter
settings.
Optical loop
system
Optical loop Coaxial bus
system system
MELSEC-Q
Coaxial bus Reference
system section
Section 4.7.1
Section 4.7.2
Section 4.7.3
Section 4.9.2
Data link status
Reference
(cyclic transmission or
section
transient transmission)
Pause Section 4.10.1
Pause Section 4.10.2
Pause Section 4.10.3
Continue Section 4.10.4
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