Toshiba V Series Manual page 162

6. Troubleshooting
Symptom
An I/O bus error has been
detected.
Trouble is detected in the PI/O
module external power supply.
The analog Output data do not
agree with the real values.
A read-back error is detected
in the analog output.
Is the distributor alarm
indicator (SDA01) lit?
148
Table 6.1 When the system does not operate correctly (part 2)
Is the I/O bus cable connected
securely?
Is the termination connector
connected to the last stage
terminal block unit?
Are the terminal blocks and
communication modules mounted
securely on the communication
base unit?
Are the PI/O module modul
numbers set correctly?
Is the external power supply wired
correctly to the terminal block unit
terminal block?
In the case of the relay
connection unit, is power supplied
correctly to the external relay
unit?
Are the external line terminal
block and connector fixed to the
main unit with screws?
Is the external power supply at
the prescribed voltage?
Is the external line terminal block
main unit fixed in place with
screws?
Is the Output open?
Is the Output signal polarity
reversed?
Is an analog signal from the same
power supply connected to an
uninsulated PI/O module?
In the case of current Output, is an
I/V conversion board mounted on
the terminal block?
Is the Output range registered
correctly?
Is the external line terminal block
main unit fixed in place with
screws?
Is the output open?
Is the polarity of the wiring to the
load reversed?
Is the external load resistance
within the specifications?
Has the external power supply
voltage dropped?
Is there excess current in the
output (Goes off by turning OFF
sensor power switch).
Checks
Insert the cable connector all the
way in, and lock in place.
Connect the termination connector.
Tighten the screws securely.
Set the numbers correctly.
Connect correctly.
Supply power to the relay unit.
Fix the external wire and terminal
block in place with screws.
Supply the prescribed voltage.
Fix external line terminal block with
screws
Connect the prescribed signal.
Connect the signal polarity
correctly.
Use an insulated PI/O module for
analog signals from different power
supply systems.
Set the I/V conversion board in
place, then apply the current
Output.
Register the range being used.
Fix the external line terminal block
in place with screws.
Connect a load.
Check the polarity, and connect
correctly.
Apply a load of 0 to 750  when
electricity is flowing.
Supply the rated power.
Check the wiring and sensor where
the excess current occurs.
Action