GE CB Watch 3 User Manual

CB Watch 3 User Manual v6.3 - May 2019 Page 42 of 100
HMI: Measurements/Alarms
Figure 57 – Excessive moisture alarm
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.
Figure 58 – Linear gas pressure extrapolation
• 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:

GE CB Watch 3 Specifications

General

Brand	GE
Model	CB Watch 3
Category	Measuring Instruments
Language	English