Mitsubishi L26CPU-BT, Руководство пользователя

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5 SYSTEM CONFIGURATION
5.2.3 Precautions on the system configuration
The system should be designed with the following considerations to prevent mis-input
from the remote I/O modules:
(1) When powering on or off
Start the data link after turning on the power to remote I/O modules. Turn off the
power to remote I/O modules after stopping the data link.
During operation
During stop
ON
OFF
Master module
(data link status)
Remote I/O module
(power status)
Data link start Data link stop
(2) During momentary power failure of remote I/O modules
When a momentary power failure occurs in the power (24 V DC) supplied to
remote I/O modules, mis-input may occur.
(a) Cause for mis-input due to a momentary power failure
The remote I/O module hardware uses the power by internally converting
the module power (24 V DC) to 5 V DC.
When a momentary power failure occurs in a remote I/O module, the
following condition occurs:
(Time for the 5 V DC power in the remote I/O module to turn off) >
(Response time for input module on off)
Therefore, mis-input occurs when a refresh is performed within the time
indicated by 1) in the figure below.
Remote I/O module
(module power supply and input
external supply power)
Remote I/O module (internal 5 V DC)
Input (Xn)
1)
When the input external power supply turns OFF, the
input (Xn) turns OFF after the response time for the
input module to change from ON to OFF.