Mitsubishi Electric WS0-CPU0 Operating Manual page 214

Chapter 9
211
Logic programming – Function blocks
Muting total time
The Muting total time is used in order to limit the maximum duration of the muting
sequence. If the set value for the Muting total time is exceeded, the Muting error
and Fault present outputs change to High and the Enable output changes to Low.
The timer for the Muting total time begins when the muting function is activated,
indicated by the transition of the Muting status output to High. The timer for the
Muting total time is stopped and reset to zero when the muting function changes to
Low. If the optional Conveyor input is used, the timer for the Muting total time
pauses when the Conveyor input is High, indicating that the conveyor belt has
stopped.
Add. muting time when ESPE is clear
The Add. muting time when ESPE is clear parameter is used when the Muting end
condition has been configured as With ESPE. If the ESPE does not always detect
the muting end exactly because of irregularities in the material or the transport means,
you can increase the availability of the machine by configuring an additional muting
time of up to 1000 ms. Only in this case does the Add. muting time when ESPE is
clear parameter determine the additional muting time after the OSSDs of the ESPE
have returned to High, i.e. that the safety light curtain is no longer interrupted.
Concurrency monitoring time
The Concurrency monitoring time is used to check whether the muting sensors are
activated simultaneously. This value specifies the maximum duration for which each of
the two dual-channel evaluated muting sensor inputs may have different values
without this being evaluated as an error. This means that input pair A1 and A2 or input
pair B1 and B2 must have equivalent values before the Concurrency monitoring
time has expired.
Concurrency monitoring begins with the first change of an input value of a muting
sensor. If the Concurrency monitoring time has expired and the two inputs of an
input pair still have different values, an error occurs.
If the concurrency monitoring determines an error for at least one input pair, the
function block indicates this error by setting the Muting error output to High.
Sensor signal gap monitoring
Occasionally faults occur in the output signals of muting sensors that may not be
relevant for muting. The Sensor signal gap monitoring function allows to filter out
brief faults without muting being interrupted.
When Sensor signal gap monitoring is enabled, a Low signal from a muting sensor
input is ignored for the duration of the set value for Sensor signal gap monitoring.
The function block continues to interpret this signal as an uninterrupted High as long
as only one sensor per pair A1/A2 or B1/B2 has a signal gap. If a signal gap has been
detected at a sensor, the simultaneous occurrence of a further signal gap at the other
sensor of the sensor pair results in the termination of muting.