Measurement Computing LogBook Series - Manual (Page 145)

Software Reference 989592 LogView LV-19
Analog Input Channel Configuration, 2-Point Cal Tab Selected
2-Point Cal Tab, Partial Close-up
4. Apply a voltage to channel 1 near the bottom end of the measurement range.
5. Type the known value into the Set P1 column for the associated channel.
6. Click the button under the Get P1 heading. This allows you to read the channel and
calculate the required offset. Note that the channel value read is now shown in the Actual P1
column and the Cal Offset column now shows the correction factor.
7. Apply a voltage to channel 1 near the top of the measurement range.
8. Type the known value into the Set P2 column for the associated channel.
9. Click the button under the Get P2 heading to read the channel and calculate the required
offset and scale. Note that the channel value is now shown in the Actual P2 column. The
Cal Offset and Cal Scale columns now show the correction factors.
For channels using thermocouples, it may be impractical to provide more than one
calibration point. In such cases, apply just one known point in Set P1, and click the
corresponding button. This will adjust the offset only, which is typically the
source of most transducer error.
For strain gages, use the User Scaling tab to enter the transducers' transfer functions (e.g.,
volts to pounds), then use 2-point calibration to periodically trim the scale and offset. This
eliminates the need to manually adjust sensors using hardware potentiometers.