LSIS XGT Series - Troubleshooting Example

Chapter 3 Operation Order and Installation
3-37
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3.7.4 Troubleshooting Example
Possible troubles with various circuits and their corrective actions are explained.
(1) Input circuit troubles and corrective actions
The followings describe possible troubles with input circuits, as well as corrective actions.
Condition
Cause
Corrective Actions
Input signal
doesn’t turn
off.
Leakage current of external device
(Such as a drive by non-contact switch)
 Connect an appropriate register and capacity,
which will make the voltage lower across the
terminals of the input module.
 CR values are determined by the leakage
current value.
 Recommended value C : 0.1 ~ 0.47 ㎌
R: 47 ~ 120  (1/2W)
or make up another independent display
circuit.
Input signal
doesn’t turn
off (Neon
lamp may be
still on)
Leakage current of external device
(Drive by a limit switch with neon lamp)
Input signal
doesn’t turn
off.
Leakage current due to line capacity of
wiring cable.
 Locate the power supply on the external
device side as shown below.
Input
signal
doesn’t
turn off.
Leakage current of external device
(Drive by switch with LED indicator)
 Connect an appropriate register, which will
make the voltage higher than the OFF voltage
across the input module terminal and common
terminal.
C
AC input
R
~
C
External device
AC input
R
Leakage current
~
C
External device
AC input
R
Leakage current
AC input
External device
~
External device
AC input
Leakage current
~
External device
DC input
R
Leakage current
DC input
R