CB Watch 3 User Manual
v6.3 - May 2019
Page 28 of 100
Auxiliary contact supervision
Because we have a travel sensor, when we get the signal from the 52a and 52b auxiliary
contacts that the CB has opened or closed, we can check the corresponding position of
the travel sensor (which should be within the pre-defined min and max positions) to
confirm that the CB has physically moved to the correct position.
Figure 37
–
Monitoring the auxiliary contacts
Since the travel sensor displacement limits (min and max in mm) for the physical open
and closed positions have been entered (with tolerances) in the setup, an alarm is then
raised if the travel sensor position is not within these limits.
HMI: Measurements/Alarms
Figure 38
–
Monitoring the auxiliary contacts
•
Close position alarm: Despite what 52a auxiliary sensor indicates, travel sensor
indicates that CB is outside defined closed min/max positions
•
Open position alarm: Despite what 52b auxiliary sensor indicates, travel sensor
indicates that CB is outside opened defined min/max positions