Mitsubishi Q01CPU User Manual

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12.5 I/O Module Troubleshooting
12.5.1 Input circuit troubleshooting
12
TROUBLESHOOTING
12.5 I/O Module Troubleshooting
This section explains possible problems with I/O circuits and their corrective actions.
12.5.1 Input circuit troubleshooting
The following describes possible problems with input circuits and their corrective actions.
Table12.19 Input crcuit problems and corrective actions
Condition Cause Corrective Action
Example 1
Input signal is
not turned
OFF.
• Leakage current of input switch
(e.g. drive by non-contact switch).
• Connect an appropriate CR so that the voltage
across the terminals of the input module
becomes lower than the OFF voltage.
It is recommended to use 0.1 to 47 F+47 to
120 (1/2W) for the CR constant.
Example 2
Input signal is
not turned
OFF.
• Drive by a limit switch with neon lamp.
• Same as Example 1.
• Provide an independent display circuit
separately.
Example 3
Input signal is
not turned
OFF.
• Leakage current due to line capacity of wiring
cable.
(Line capacity C of twisted pair wire is approx.
100 pF/m).
• Same as Example 1.
(However, leakage current is not generated
when the power supply is located in the input
equipment side as shown below.)
Example 4
Input signal is
not turned
OFF.
• Drive by a switch with LED display.
• Connect an appropriate resistor so that the
current across the input module becomes lower
than the OFF current.
*: A calculation example of the resistance to be
connected is shown on the following page.
Table12.19 Input crcuit problems and corrective actions (Continued)
AC input
Input
module
Leakage
current
Power supply
Input
module
AC input
R
AC input
Input
module
Leakage
current
Power supply
AC input
Input
module
Leakage
current
Power supply
AC input
Input
module
Power supply
DC input (plus common)
Input
module
Leakage current
DC input (plus common)
Input
module
Resister

Mitsubishi Q01CPU Specifications

General

Brand	Mitsubishi
Model	Q01CPU
Category	Controller
Language	English