5520A
Operators Manual
4-18
While the ac function ranges are directly compatible for sine waves, the rms content of
the other waveforms is less apparent. This characteristic leads to subtle calibrator range
changes. For example, if you enter a sine wave voltage of 6 V (rms assumed), the
selected range is 3.3 to 32.9999 V. If you then use the softkeys to change from a sine
wave to a triangle wave, for example, the display changes from 6 V rms to 6 V p-p. This
translates to 6 V p-p x 0.2886751 = 1.73205 V rms, and the range switches to 0.33 to
3.29999 V. The Output Display shows the range change because the sine wave voltage is
displayed as 6.0000, the resolution for the 3.3 to 32.9999 V range, while the triangle
wave is displayed as 6.00000, the resolution for the 0.33 to 3.29999 V range.
You need to know the active range to enter the correct values for voltage offset because
the maximum offsets are range specific. For example, the maximum peak signal for the
3.3 to 32.9999 V range is 55 V while the maximum peak signal for the 0.33 to 3.29999 V
range is 8 V. This means in the example above, the 6 V rms sine wave could have offsets
applied up to the maximum peak signal of 55 V because the active range is 3.3 to
32.9999 V, while the 6 V p-p triangle wave could have offsets applied up to the
maximum peak signal of 8 V because the active range is 0.93 to 9.29999 V. See
“Specifications” in Chapter 1 and “Entering a DC Offset” later in this chapter for more
information about dc offset voltages.
4-20. Auto Range Versus Locked Range
A softkey is provided to toggle between the ranging method auto or locked. This feature
is available only for single-output dc volts and dc current outputs.
nn063f.eps
When auto is selected (the default setting), the calibrator automatically selects the range
that provides the best output resolution. When locked is selected, the calibrator locks the
selected range and will not change ranges when you are editing the output, or entering
new outputs. Values lower or higher than the locked range are not allowed. The locked
selection is usually made when you do not want range changes that may cause a small
perturbation in the output, e.g., when checking the linearity of a given multimeter range.
4-21. Setting the Output
Setting the calibrator output is similar to entering values into a calculator: press the keys
that represent the value you desire and then press a units key to identify which of the
volts, amps, hertz, etc. you want the value to represent. The control display indicates the
value and units you select as you type them into the calibrator. Once you are satisfied
with the value and units, pressE. If the output display indicates STBY, press O
to output the selection. The display of a small “u” (unsettled) in the Output Display
indicates the calibrator is allowing for its internal circuitry to settle.
For example, to set the output to 10 V dc, press:
1→ 0 → V → E→ O
To Next Page
Loading...
