Fluke 2680A User Manual page 126

2680A/2686A
Users Manual
The dialog box entries include:
CH #
Computed channels in the 2680 Series are assigned channel numbers from 901
to 960. Computed channels in the NetDAQ are numbered 21-30.
Label
Use the label field to identify where the computed channel is used.
Unit Label
Used to identify the unit of measurement (for example VDC, Ohms, Hz, °C
or °F).
Function
You can take the average of readings from multiple channels, subtract the
measurement of one channel from the measurement of another channel or an
average, or generate an equation based on measurements.
Alarm Type
Use Normal alarm type to generate an alarm if the measurement goes above or
below the Alarm 1 or Alarm 2 level. Use Band alarm type to alarm if the
signal falls between two levels.
The NetDAQ 2640A and 2645A instruments do not have the Band
alarm type.
Alarm 1 or Alarm 2
Each channel has two alarms. You can set the alarms to Off, Low, or High. A
Normal alarm condition occurs when a measurement falls below a low alarm
value (Low) or rises above a high alarm value (High). A Band alarm type
generates an alarm when the measurement value is between the two alarm
limit values. Fluke DAQ records all alarm conditions in an alarm database.
Each of the two Alarm limits (one for the Band type alarm) has a Digital
Output button to select Digital or relay outputs that go active when an alarm is
generated from the alarm limit. Use Channel Alarm Trigger Select if channel
reading will be used to provide alarm trigger.
Digital Output
Used to output a digital signal or close a relay if an alarm is detected.
Use Channel as Alarm Trigger
Select if channel reading will be used to generate an alarm trigger.
Scan With Modules
Calculate the computed channel any time the selected modules are scanned.
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Note