1-12
IM WT310E-02EN
1.5 Auto Range, Overrange, and Error Indications
During Measurement
Overrange Indication
The measured voltage and rated current values are determined to be overrange when they exceed
140%* of their rated range. When auto range is enabled, the range is automatically increased, but if
a values exceeds 140%* of its maximum range, it is determined to be overrange, and the following
indication appears.
* 280% when the crest factor is set to 6A
In the case of the maximum current range (40 A range) on the WT310EH, over-range occurs in the
following conditions.
• 110% when the crest factor is set to 3 or 6
• 220% when the crest factor is set to 6A
Computation Overflow Indication
If a computed value cannot be displayed using the specified decimal place or unit, the following
indication appears.
Auto Range Monitor Indications
When an input signal meets the conditions for auto range switching, an indicator lights.
WT310E/WT310EH
WT332E/WT333E
Colors and Meanings of Auto Range Monitor Indicators
Color
Description
Red
Peak overrange
Magenta
Greater than 140%
1
(280%
3
) of the rated range (overrange)
Yellow
Greater than 130%
2
(260%
3
) of the rated range and not more than 140%
1
(280%
3
) (condition for
raising the auto range)
Cyan
30% or less of the rated range (condition for reducing the auto range)
If the range is already at the minimum measurement range, this indicator will not light even when
values are 30% or less of the rated range.
1 On the WT310EH, the current is determined to be overrange when it exceeds 110% (220%
3
) of the maximum
current range (40 A range).
2 On the WT310EH, the current is determined to be overrange when it exceeds 100% (200%
3
) of the maximum
current range (40 A range).
3
When the crest factor is set to 6A
Indications When the Measured Value Is Too Small
When the measured voltage or current is 0.5% or less of the rated range (1% or less when the crest
factor is set to 6 or 6A), the following indications appear. These indications only appear when the
measurement mode is RMS or VOTLAGE MEAN.
Function
Indication
Voltage, current, apparent power, or reactive power
A zero appears.
Power factor or phase angle
