Figure 57 - Excessive Moisture Alarm; Figure 61 - Linear Gas Pressure Extrapolation - GE CB Watch 3 User Manual

HMI: Measurements/Alarms
Short and long-term horizons
The rate of change of the pressure can be calculated using two sets of values:
• values in the "short-term" stack measured every 10 minutes
• values in the "long-term" stack measured every day
These values are used to calculate a linear extrapolation/forecast of the pressure in the
future at the end of either the "short-term" or "long-term" time horizon.
• Short-term extrapolated pressure at 20°C: future value computed using linear
regression and a history of 2.5x the short-term horizon
• Long-term extrapolated pressure at 20°C: future value computed using linear
regression and a history of 2.5x the long-term horizon
Note: when there are not enough data points recorded to date to calculate the short or
long-term trend, then the corresponding "stack not enough" alarm flag is set to indicate
that the value in the register may not be accurate. The value is not displayed in the HMI
and is replaced by a "-" instead.
The time horizons need to be defined first:
CB Watch 3 User Manual
Figure 57 – Excessive moisture alarm
Figure 58 – Linear gas pressure extrapolation
v6.3 - May 2019 Page 42 of 100