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IM WT1801-01EN
Selecting All Input Elements (ALL)
At the same time, you can select the currently selected element and all elements that meet the following
conditions. You can set their voltage and current ranges at the same time.
Conditions for Simultaneous Element Selection
• Only input elements of the same type (50 A input or 5 A input) can be selected.
• Only input elements whose valid measurement range settings are the same can be selected.
Initial Values for Simultaneously Selected Elements
The voltage range, current range, and auto range on/off settings of the element that was selected before you
selected the other elements are copied to all the other selected elements.
After you have selected all the input elements, changes that you make to the voltage range, current range, and
auto range on/off settings affect all the selected input elements.
To disable simultaneous selection and specify independent input element settings, press ELEMENT.
Voltage Range (RANGE UP/DOWN (V))
The voltage range can be fixed (when auto range is set to off) or determined automatically (when auto range is
set to on).
Fixed Ranges
When the voltage range is fixed, you can select a range from the available options. The selected voltage range
does not change even if the amplitude of the input signal changes. Set the range in reference to the rms value of
the input signal.
When the
Is Set to CF3
You can select from 1.5 V, 3 V, 6 V, 10 V, 15 V, 30 V, 60 V, 100 V, 150 V, 300 V, 600 V, and 1000 V.
When the Crest Factor Is Set to CF6
You can select from 0.75 V, 1.5 V, 3 V, 5 V, 7.5 V, 15 V, 30 V, 50 V, 75 V, 150 V, 300 V, and 500 V.
Auto Range
• Set the range in reference to the rms value of the input signal. For example, if you are applying a 100-Vrms
sinusoidal signal, set the range to 100 V.
• When measuring a signal other than a sine wave (such as a distorted wave), you can obtain accurate
measurements by selecting the smallest measurement range that does not produce any of the conditions
below.
• The input peak over-range indicator at the top center of the screen illuminates or blinks in red.
• The measured values of the voltage and current are indicated as being overload values (“-OL-”).
• The peak over-range indicator may not illuminate or blink in the following cases.
• If the pulse width is narrow, and the peak value of the waveform cannot be acquired at the sampling rate
of the WT1800 (approximately 2 Ms/S).
• If the high frequency components of the pulse waveform attenuate due to the bandwidth limitations
of the WT1800 measurement circuit, causing the waveform peak value to be less than the peak over-
range detection level.
• When a signal with the peak which becomes more than about 10 times of the range is input, it takes about
1 second to change the range.
• When the secondary output of a VT (voltage transformer) is being applied to the voltage input terminal, set
the voltage range according to the maximum value of the VT output. Then, use the scaling feature to set
the VT ratio.
2 Fundamental Measurement Conditions
