Fluke Calibration 5730A, Operator'S Manual, Page: 105 / 260

Front-Panel Operation
Program a Scale Factor
4
4-41
Program a Scale Factor
Use the Scale selection in ac and dc voltage and current functions to apply a scale factor
to subsequent outputs. The Scale selection is shown by touching the + icon on the right of
the display above the bottom row of selections. After a scale factor is established, the
correct proportion of it is applied to all subsequent entries to compensate for a UUT scale
error. Touch
Scale again to turn off this scale. Both the scale error and the keypad-
entered value are shown on the display with the true output value.
The Scale selection can be used to establish a reference full-scale endpoint. This endpoint
can be used with the Offset selection to check the linearity of a UUT. (See the example
under “Linearity Checking With Offset and Scale”.)
To program a scale factor:
1. Set the 5730A Calibrator to output a level just below the UUT full-scale endpoint.
For example, use 19.9 V for a UUT that ranges at 20 V.
2. Adjust the Calibrator output with the rotary knob (and arrow keys if necessary) until
the UUT reads the selected correct output level (19.9 V in this example).
3. Touch Scale . This stores a scale factor that would apply this adjustment if this
output level were selected again.
Subsequent Calibrator output values will be scaled by this factor. In the example in
Figure 4-8, the meter reading was 3 mV low at 19.9 V. To compensate, the Calibrator
was adjusted to 19.003 V to get a reading of 19.9 V on the meter. Note that the Calibrator
is adjusted in the opposite direction of the meter scale error. So, a factor computed in the
subsequent equation is applied to subsequent Calibrator output settings until the Scale
selection is cleared:
1 -
19.9 V – 19.903 V
= 1.000151
19.9 V
Extending this example, if the Calibrator is now set to 10 V, the actual output shown on
the display is 10.00151 V.