Troubleshooting - Toshiba V Series Manual

6. Troubleshooting

When the intelligent PI/O system is actually run, it sometimes does not run as expected. In such a
case, before judging that a system breakdown has occurred, perform the checks in Table 6.1 and
take the action indicated.
Symptom
The LED on the PI/O module
below the communication base
unit fails to light up. Or, it lights
up briefly and then immediately
goes off.
Serial bus error is detected.
NOTE:

When troubleshooting, use the following manuals together with this one.
Intergrated Controller Vseries Engineering Tool Manual 6F8C1006

Table 6.1 When the system does not operate normally (part 1)
Is the system power supply
correctly connected to the
communication base unit?
Is the I/O bus cable connected
securely?
Is the system power supply
voltage within the rating?
Are the communication modules
all mounted securely on the
communication base unit terminal
block?
Is the serial bus wiring to the
communication base unit correct?
Is the termination resistor
connected to the last stage
communication base unit terminal
block correctly?
Are the communication base unit
terminal block screws tightened
securely?
Are the communication base unit
terminal blocks and the
communication modules mounted
securely?
Are the communication base unit
numbers set correctly?
Checks
Check the polarity and connect
correctly.
Insert the cable connector in all the
way, and lock it in place.
Check for power supply overload or
breakdown.
Fix in place securely with screws.
Recheck the wiring paths, and wire
correctly.
Connect the termination resistor
correctly to the terminal section.
Tighten the screws securely.
Tighten the screws securely.
Set the numbers correctly.
6. Troubleshooting
Action
147