Details Of I/O Signals - Mitsubishi MELSEC Q Series User Manual

3 SPECIFICATIONS

3.3.2 Details of I/O signals

Device No. Signal Name
X0 Module ready
Warning output
X8
signal
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I/O signals for the A/D converter modules are explained in detail below.
(1) Input signals
(1) When the programmable controller CPU is powered on or reset, this signal turns on
once the preparation for A/D conversion has been completed, and A/D conversion
processing is then performed.
(2) In either of the following states, the Module ready (X0) turns OFF.
• During offset/gain setting mode (A/D conversion processing is performed.)
• When the A/D converter module has a watchdog timer error
processing is not performed.)
(1) The Warning output signal (X8) turns ON at detection of a process alarm or rate alarm.
(a) Process alarm
1) This signal turns ON when the digital output value falls outside the setting range
set to the process alarm upper/lower limit values (buffer memory addresses 86
to 117: Un\G86 to Un\G117) on any of the channels enabled for A/D conversion
after the process alarm function has been made valid.
2) As soon as the digital output values return to within the setting ranges on all
channels enabled for A/D conversion, this signal turns OFF automatically and
the ALM LED is also extinguished.
(b) Rate alarm
1) This signal turns ON when the varying rate of the digital output value falls
outside the varying rate range set to the rate alarm upper/lower limit values
(buffer memory addresses 122 to 137: Un\G122 to Un\G137) on any of the
channels enabled for A/D conversion after the rate alarm function has been
made valid.
2) As soon as the varying rates of the digital output values return to within the
preset varying ranges on all channels enabled for A/D conversion, this signal
turns OFF automatically and the ALM LED is also extinguished.
Warning output flag
(Buffer memory address 48: Un\G48)
Warning output signal (X8)
1 A watchdog timer error occurs when the program calculations are not completed within the
scheduled time due to malfunctions of A/D converter module hardware.
When a watchdog timer error occurs, the RUN LED for the A/D converter module turns off.
Description
Performed by the A/D converter module
Performed by the sequence program
0
MELSEC-Q
1
(A/D conversion
Warning occurrence
(Process alarm, rate alarm)
0
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