Computed Channels

This dialog box is available by clicking next to Computed Channel at the bottom of the Configure Channels tab. A computed channel mathematically combines the measurements on measured channels, other computed channels, or measured or computed channels and a constant (channels must be part of the current scan list).

Computed Channel Name

Enter a descriptive name for the computed channel. For example, Channel 101 plus 303.

Note: To add a more detailed comment to a computed channel, right-click on the channel then click Comment.

Computation Type

Select either Basic Math, Power Equations, Strain Equations, Polynomial, General Equation Editor or Statistic as the Computation Type, with the respective operator type from the Operation column.

Computation Type	Operation
Basic Math:	Add
	Subtract
	Multiply
	Divide
	Square
	Square Root
Power Equations:	dB
	dBm
	dBV
Strain Equations:	Full Bridge (Bending)
	Half Bridge (Bending)
	Quarter Bridge
Polynomial:	Fifth Order
General Equation Editor:	General Equation Editor
Statistic:	Min
	Max
	Average
	Standard Deviation

Formula

This area displays the formula and a description involving the selected Computation Type and Operation type.

For Strain Equations, click Help... button to view the definitions of the formula elements and More... button to define constant values. See Strain Equation Constants for further details.

For Polynomial, click More... button to define the coefficient parameters, and values of each variable. See Polynomial coefficients for further details.

For General Equation Editor, click Edit button to define your own general equation. See General Equation Editor for further details.

For Statistic, click Edit button to perform statistic operation (Min, Max, Average, and Standard Deviation). See Statistic for further details.

Argument1

Select Channel to use a channel as Argument1 in your formula. Use the drop-down list to select a measured channel or another computed channel.

Select Constant to provide a value for Argument1 in your formula. Enter the value in the Argument1 field.

Argument2

Select Channel to use a channel as Argument2 in your formula. Use the drop-down list to select a measured channel or another computed channel.

Select Constant to provide a value for Argument2 in your formula. Enter the value in the Argument2 field.

Note: At least one argument must be a channel. Both arguments cannot be constants.

Display Units

Use the drop-down list to select from a Standard list of measurement units or None for the result. Select Custom to specify custom units with up to eight characters including letters, numbers, and special characters.

When finished specifying the computed channel, click OK to add the channel to the scan list. The computed channels are given a 900-Series channel number for 34970/72A and DAQ970A/DAQ973A |9000-series for 34980A and the computations are done in the order of appearance in the scan list (top to bottom).

Notes:

To delete a computed channel, right-click on the channel then click Delete.
When a scan list channel is an argument for a computed channel, a dependency is formed. Removing the scan list channel from the scan list causes the computed channel to be deleted. Similarly, when a computed channel is used as an argument for another computed channel, deleting the computed channel that is the argument will cause the dependent computed channel to be deleted.
To append a new computed channel to an existing computed channel, right-click on the channel then select Append New Channel(s). You can append more than one computed channels.