Servomex 07931001B, Руководство оператора

Страница: 73 / 221

07931001B revision 6 © Servomex Group Limited. 2020
59
Alarm mode Hysteresis effect
Low alarm
Once a low alarm condition is activated, the alarm condition is not
deactivated until a sample measurement is above:
Alarm level + hysteresis level
High alarm
Once a high alarm condition is activated, the alarm condition is not
deactivated until a sample measurement is below:
Alarm level - hysteresis level
Example : If a low alarm has an alarm level of 18% and a hysteresis level of 1%, the
alarm is activated when a sample measurement is <18% and the alarm is not
deactivated until a sample measurement is >19%.
Figure 4-20: Set alarm level and hysteresis menu
Hint:
Make sure that the measurement alarm and hysteresis levels are not
too close to the expected sample measurements. If your sample gas
concentrations contain minor variations that are acceptable, spurious
alarms will be reduced.
Follow option
Each measurement has a 'Follow' option:
Hint:
If you configure one measurement alarm as low and the other as high,
make sure that the high alarm and hysteresis levels are higher than
the low alarm and hysteresis levels. If you do not, the analyzer can be
permanently in an alarm condition until you correct the levels.