Advertisement
4.
SELF-DIAGNOSTIC TESTING
(1)
Self-diagnostic tests
are done
to check (a) the hardware
of the
AJ72TSB and, (b) twisted
pair cable
disconnections between the
AJ72TZSB
and the other
stations.
Select one of the three rnodes using the mode setting switch as shown below:
I
7
1
Self-loopback test
Checks the hardware using an
independent AJ72T25B.
(2) Only the self-loopback
t e s t
procedure is explained here. The MELSECNET,
MELSECNETB data link system reference manual gives details about other
procedures.
4.1
Self-bopbeck Test
(1) Self-loopback test
Checks the hardware using an independent AJ72T25B.
(2) Test procedure
The self-loopback
test
procedure is shown below:
--Select
the self-loopback test.
switch to 7.
--Rwet
the AJ72T25B using @,reset switch.
......
Execute the t e a about seven
sehnds after resetting.
The LED shows the result
of the test.
/
Complete
1
(3) Test results
The LEDs on the front o
If
the
,
AJ72T25B show the test results.
(a) If the AJ72T25B is working normally, the LED flashing begins with
CRC, followed by OVER, AB.IF, TIME, DATA, and UNDER.
(b) When the AJ72T25B works abnormally, the LED corresponding to the
error goes
ON.
If the test ends before completion, the hardware could
be faulty.
4 - 1
Advertisement
