Mitsubishi FX2N-64CL-M, User Manual

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FX2N-64CL-M CC-Link/LT Master Block Troubleshooting 12
12-9
12.5 Prevention of erroneous inputs to and outputs from remote I/O module
In order to prevent erroneous inputs to and outputs from remote I/O modules, design the
system under consideration of the contents described below.
1) When setting the power to ON or OFF
Turn ON the power to remote I/O modules (power adapter or dedicated power supply) first,
and then start the data link.
Stop the data link first, and then turn OFF the power to remote I/O modules (power adapter
or dedicated power supply).
2) When the power is interrupted instantaneously in a remote I/O module
When the power (24V DC) supplied to a remote I/O module is interrupted instantaneously,
erroneous inputs may occur.
a) Cause of erroneous inputs due to instantaneous power interruption
The hardware of a remote I/O module converts the unit power (24 VDC) into 5V DC
inside, then uses it.
If instantaneous power interruption occurs in a remote I/O module,
(Time until 5V DC inside remote I/O module turns OFF)
> (Response time for "ON
→
OFF" of input unit)
As a result, if refresh is executed in the period shown in (A) below, erroneous inputs
occur.
(Erroneous inputs may occur especially while the input response time is set to high-
speed input type.)
FX
2N
-64CL-M
(data link status)
Remote I/O module
(power supply status)
Executing
Stopped
ON
OFF
Data link start Data link stop
Remote I/O module
(Unit power supply and external
power supply to input area)
Remote I/O module
(internal 5V DC)
(A)
When the external power supply to the
input area is set to ON, the input
(Xn) turns ON after the response time
for "OFF
→
ON" of the input unit.
When the external power supply to
the input area is set to OFF, the input
(Xn) turns OFF after the response
time for "ON
→
OFF" of the input unit.
Input (Xn)