Programming A Scale Factor - Fluke 5700A Series II Operator's Manual

5700A/5720A Series II
Operators Manual

4-49. Programming a Scale Factor

You can use the S key in ac and dc voltage and current functions to apply a scale
factor to subsequent outputs. After you establish a scale factor, the correct proportion of
it is applied to all subsequent entries to compensate for a UUT's scale error. You turn off
this scale factor by pressing S again. Both the scale error and the keypad-entered value
are shown on the Control Display. The Output Display shows the true output value.
The S key may be used to establish a reference full-scale endpoint, which you can use
with o to check the linearity of a UUT. (See the example under "Linearity Checking
Using Offset and Scale".)
To program a scale factor, proceed as follows:
1. Set the calibrator to output a level just below the UUT full-scale endpoint. For
2. Adjust the calibrator's output with the rotary knob (and arrow keys if necessary) until
3. Press S . This stores a scale factor that would apply this adjustment if this output
Subsequent calibrator output values will be scaled by this factor. Using the example of
Figure 4-8, the meter reading was 3 mV low at 19.9V. To compensate, the calibrator was
adjusted to 19.003V to get a reading of 19.9V on the meter. Note that the calibrator is
adjusted in the opposite direction of the meter's scale error. So, a factor computed in the
following equation is applied to subsequent calibrator's output settings until S is
cleared:
Extending this example, if you now set the calibrator to 10V, the actual output (showing
on the Output Display) is 10.00151V.
4-46
example, you might use 19.9V for a UUT that ranges at 20V.
the UUT reads the selected output level correctly (19.9V in this example).
level were selected again.
1 −
−
19 9 . V 19 903 . V
= 1.000151
19 9 . V