Loop Disconnection Detection Judgment Time (Buffer Memory Address 59, 91: Un\G59, Un\G91); Loop Disconnection Detection Dead Band (Buffer Memory Address 60, 92: Un\G60, Un\G92) - Mitsubishi Electric MELSEC-Q Series User Manual

3 SPECIFICATIONS
3.5.30 Loop disconnection detection judgment time
(buffer memory address 59, 91: Un\G59, Un\G91)
3.5.31 Loop disconnection detection dead band
(buffer memory address 60, 92: Un\G60, Un\G92)
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(1) The loop disconnection detection function detects errors in the control system
due to a load disconnection, external operation device fault, sensor
disconnection and the like.
No temperature change of greater than 2
than 0.2% of full-scale for micro voltage, voltage and current within the loop
disconnection detection judgment time is judged as a loop disconnection.
(2) Set a value longer than the time taken to vary the temperature 2
of 0.2%.
(3) When auto tuning is performed, a value twice longer than the integral time is set
automatically as the loop disconnection detection judgment time.
However, if the loop disconnection detection judgment time is set to 0 before
auto tuning is performed, the loop disconnection detection judgment time is not
stored.
(4) The setting range is 0 to 7200 (0 to 7200s).
POINT
If loop disconnection alert occurs frequently despite normal operation of a sensor
and external operation device, check if the capacity of external device (such as
heater and cooling fan) is enough.
If not, set a time value longer than time required for varying 2
manipulated value 100%.
(1) To prevent the false alert of loop disconnection detection, set the no alert area
(area where no loop disconnection will be detected) around the set value.
(2) The setting range is
for thermocouple input and greater
full-scale.
MELSEC-Q
(2 F) or that
or 0.2% with
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