Measurement Computing DBK Part 2 - Manual (Page 60)

DBK43A & DBK43B, pg. 40 899892 DBK Option Cards and Modules
9. Select Indicators \ Enable Input Reading Column from the menu bar to display the excitation
values for each channel.
10. Set the voltage to V
D
, as derived above, for each transducer. This is accomplished by
adjusting the trimpots labeled GAIN and SCALE for the associated channel. The GAIN
trimpot provides for course adjustment. The SCALE trimpot provides for fine tuning.
11. Select Indicators \ Disable Input Reading Column from the menu bar.
12. DBK43A users: Return the physical NORM/CAL switches to the NORM position.
DBK43B users: Return CAL1 and CAL2 to the RUN position.
13. DBK43A users: In LogView, open the LogBook Hardware Configuration window and return
each DBK43A to NORM.
DBK43B users: In LogView, open the LogBook Hardware Configuration window and return
each DBK43B to a software switch parameter status of: 1’RUN+2’RUN.
14. Change the mode to Bridge.
Repeating the Process
Since adjusting the gain for the first time will have an affect on the offset, it is recommended that
offset and gain adjustment be performed twice for each channel.
Creating a Units Conversion Transfer Function
To make the data from your gage more useful, it should be recorded in terms of units appropriate to your
application, such as pounds, kilograms, inches, mm, or Hg. A transfer function is needed to convert volts to
these more meaningful units.
For this purpose, LogView provides a means of assigning a mathematical scale and offset to each channel.
Scale and offset information from that chapter has been repeated below for convenience.
In User Scaling, you can create a transfer function. The function allows LogView to display units that could
be more useful to you than volts. For example, you could obtain readings with pounds as the designated Units.
The reading (in pounds) will be based on the raw input value, typically Volts, and the indicated Scale and Offset
adjustment.
To create the transfer function:
1. Type the desired unit name in the Units column.
2. Select an appropriate range (e.g. unipolar).
3. Enter the linear scale relation to Volts (e.g. 25 pounds per Volt).
4. Enter any offset from 0, for example, an empty basket used in an
application reads 0.1 V.
The reading and range columns will automatically change to the adjusted values.