Dayton WT3 - Manual (Page 23)

Impedance Sweep
Use this command to perform a simple impedance sweep without the extraction of any parameters.
Driver parameters will be cleared to prevent any confusion.
Impedance Calibration...
When first installed, WT3 is calibrated to within about 2% for the impedance range under 100 Ohms.
This is adequate for measuring driver parameters. For even finer calibration you can use this command
to custom calibrate the system for your particular WT3 hardware unit. When you select this command
the impedance calibration dialog (shown below) will open.
Enter the actual value of the calibration resistor you are using (if different from the recommended 1k
Ohms). Then, connect the calibration resistor to the WT3 test leads and click OK. The software will
measure the calibration resistor and adjust its internal calibration accordingly. After calibration, you
might want to make another measurement of the calibration resistor to confirm the new calibration. By
design, WT3 is most accurate in the lower impedance range with accuracy decreasing at higher
impedances (above 1k Ohms). Calibration in the lower impedance range will typically be improved to
within 1% following calibration at 1k Ohms with the 1% resistor included with the unit. You can
actually calibrate the unit with any convenient resistor in the range from about 500 to 2k Ohms. It is
important that the actual value of the resistor be known to within 1%. High quality digital multi-meters
will often be able to measure any resistor to within 1%.
When you exit the application the new calibration will be remembered for your next session.
Impedance calibration only needs to be performed one time after the software is installed on a PC.