Input Signal Error Detection Function - Mitsubishi MELSEC-L Series User Manual

8.6

Input Signal Error Detection Function

Detects any analog input value that is outside the setting range.
Analog
input value
Input signal error detection signal (XC)
(1) Notification of input signal error detection
If the analog input value is above the input signal error detection upper limit value, or below the input signal error
detection lower limit value, the error is notified by Input signal error detection flag (Un\G49), Input signal error
detection signal (XC), and the flashing ALM LED.
In addition, alarm code 110
The alarm code that is stored is shown below:
(2) Operation of the input signal error detection function
The digital output value on the channel on which the error was detected is held at the value just before the error
was detected, and A/D conversion completed flag (Un\G10) and A/D conversion completed flag (XE) are turned
OFF.
In addition, once the analog input value returns within the setting range, A/D conversion resumes regardless of
the reset of Input signal error detection flag (Un\G49) and Input signal error detection signal (XC). After the first
update, A/D conversion completed flag (Un\G10) for this channel turns back ON. (ALM LED remains flashing.)
Input signal error
detection upper
limit value
CH1 Analog input
value
Input signal error
detection lower
limit value
Error
CH1 Input signal error
detection flag (Un\G49.b0)
CH1 A/D conversion
completed flag (Un\G10.b0)
Error clear request (YF)
gets stored in Latest error code (Un\G19).
110
Fixed
Input signal error channel number
Normal input value
ON
OFF
ON
OFF
ON
OFF
ON
OFF
CHAPTER 8 FUNCTIONS
Time
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