Totalflow Driver Guide - Scanner Methods (Totalflow Scanner)

Scanner Methods

A Totalflow Scanner object supports the following object-specific methods, some of which are also available as pick actions from ViewX and Virtual ViewX:

CancelPromotedScanning—This method lets you manually exit the Promoted Scanning mode. When this method is called, the scanner is configured to use the normal scanning rate and offset that are found on the scanner’s configuration form. The method takes no parameters.
ChangeGasComp—This method lets you change the gas composition that is used in the AGA-8 (compressibility) calculation in the Totalflow. This method takes the gas composition parameters and then sets them all in the Totalflow in a single transaction.

This method is also available as a pick action. As such, if your user account has the relevant permissions, you can right-click on a Totalflow Scanner object in the Database Bar, and then select the Change Gas Composition pick action. The Change Gas Composition window is displayed.

The parameters that you need to specify are listed in the table below. The parameters are listed in the order in which they need to appear in the method call. Use the App Number field to specify the number of the Application in the Totalflow for which you want to change the gas composition.

Select the Live Composition check box to change the Live Analysis Data in the Totalflow device, instead of the Fixed Analysis Data.

If you select the Normalize option, the non-zero gas composition values are adjusted in equal proportion so that so that the sum of all of the elements equals 100. The method call/pick action will be unsuccessful if the individual gas composition values do not sum to 100 and the Normalize option is not selected.

The driver does not automatically update the points that monitor the gas composition after the ChangeGasComp method is called. You will either need to call the Refresh method on the Totalflow Scanner, or wait for the next poll for points to be updated.

Parameter Name	Number	Fixed Array.Index	Live Array.Index	Type	Unit
App Number	1			byte	none
Live Composition	2			bool	none
N2 nitrogen	3	3.21	3.46	double	percent
CO2 carbon dioxide	4	3.22	3.47	double	percent
H2S Hydrogen Sulfide	5	3.23	3.48	double	percent
H2O Water	6	3.24	3.49	double	percent
He Helium	7	3.25	3.50	double	percent
CH4 Methane	8	3.26	3.51	double	percent
C2H6 Ethane	9	3.27	3.52	double	percent
C3H8 Propane	10	3.28	3.53	double	percent
C4H10 n-Butane	11	3.29	3.54	double	percent
C4H10 i-Butane	12	3.30	3.55	double	percent
C5H12 n-Pentane	13	3.31	3.56	double	percent
C5H12 i-Pentane	14	3.32	3.57	double	percent
C6H14 n-Hexane	15	3.33	3.58	double	percent
C7H16 n-Heptane	16	3.34	3.59	double	percent
C8H18 n-Octane	17	3.35	3.60	double	percent
C9H20 n-Nonane	18	3.36	3.61	double	percent
C10H22 n-Decane	19	3.37	3.62	double	percent
O2 Oxygen	20	3.38	3.63	double	percent
CO Carbon Monoxide	21	3.39	3.64	double	percent
H2 Hydrogen	22	3.40	3.65	double	percent
Ar Argon	23	3.41	3.66	double	percent
Normalize	24			bool	N/A

EnablePromotedScanning—Use this method to temporarily change the scanning rate on a Scanner object. The method takes a single input parameter: Promoted Scan Duration. The units for this parameter are seconds. Use the Promoted Scan Duration parameter to define the length of time that the Scanner object will be configured to use the Promoted Scan Rate. The scanner exits promoted scanning mode automatically once the Promoted Scan Duration expires; alternatively, promoted scanning mode can be exited manually by calling the CancelPromotedScanning method.
ResetCommCounters—Use this method to clear the communications counters that are mentioned in the section on Scanner Data Fields. The method takes no parameters.
ResetNewestEventTimes—Use this method to reset the values in the NewestEventTimes tag. The method is useful if you want to re-scan the Event Data Table from the Totalflow device. To reset all of the newest event times, call this method with a parameter of 0. To reset just a single value, call this method with the tube number for which you want to reset the NewestEventTime.
SetClock—Use this method to set the clock in the Totalflow device to the local time at the Geo SCADA Expert host. The method takes no parameters.

Further Information

Scanner Data Fields