Aalborg XFM Digital - Manual (Page 17)

5.3.2 Gas Table Settings.
The XFM Mass Flow Meter is capable of storing calibration data for up to 10 dif-
ferent gases. Digital interface commands are provided to:
- get currently active Gas Table number and Gas name
- set desired Gas Table.
5.3.3 Totalizer Settings.
The total volume of the gas is calculated by integrating the actual gas flow rate
with respect to the time. Digital interface commands are provided to:
- reset the totalizer to ZERO
- start the totalizer at a preset flow
- assign action at a preset total volume
- start/stop (enable/disable) totalizing the flow
- read totalizer via digital interface
The Totalizer has several attributes which may be configured by the user.
These attributes control the conditions which cause the Totalizer to start integrat-
ing the gas flow and also to specify actions to be taken when the Total Volume is
outside the specified limit.
Totalizer action conditions become true when the totalizer reading and preset
"Stop at Total" volumes are equal.
14
Note: Once Flow Unit of Measure is changed, the Totalizer’s
Volume/Mass based Unit of Measure will be changed automatically.
Note: By default the XFM is shipped with at least one valid calibration
table (unless optional additional calibrations were ordered). If instead
of the valid Gas name (for example NITROGEN), the LCD screen or
digital interface displays Gas designator as “Uncalibrated”, then the
user has chosen the Gas Table which was not calibrated. Using an
“Uncalibrated” Gas Table will result in erroneous reading.
Note: Before enabling the Totalizer, ensure that all totalizer settings
are configured properly. Totalizer Start values have to be entered in
%F.S. engineering unit. The Totalizer will not totalize until the flow rate
becomes equal to or more than the Totalizer Start value. Totalizer Stop
values must be entered in currently active volume / mass based
engineering units. If the Totalizer Stop at preset total volume feature is
not required, then set Totalizer Stop value to zero.