YOKOGAWA CW120 - Overrange and Other Marks Shown During Measurement

2-6
IM CW120-E
2.4 Overrange and Other Marks Shown
during Measurement
WARNING
When the overrange mark appears with the range set to a maximum, it means that the input
exceeds the maximum allowable level of the CW120/121. Do not apply an input level higher than
the maximum allowable input level.
CAUTION
When measuring an input signal level exceeding the rated range, use a voltage transformer (VT)
or current transformer (CT). When using a VT or CT, thoroughly read Section 5.3, “Wiring the
Circuit under Test with External VT/CT.”
● Overrange Indications
: Indicates an overvoltage.
This mark appears in the following conditions.
150/300 V range: If the sampled value exceeds 200% of the rated
voltage or if the rms value of the measured voltage
exceeds 110% of the rated range
450 V range: If the sampled value exceeds 156% of the rated
voltage or if the rms value of the measured voltage
exceeds 110% of the rated range
: Indicates an overcurrent.
This mark appears if the sampled value exceeds 300% of the rated
current or if the rms value of the measured current exceeds 110% of
the rated range.
TIP
The mark appears when any one of the input signals from terminals V1 to V3 satisfies the condi-
tions noted above.
The mark appears when any one of the input signals from terminals CH1 to CH4 satisfies the
conditions noted above.
indication
The CW120/121 show instead of a usual number representing the
measured value if any one of the following conditions is met.
The number representing the measured value exceeds 9999, the maximum
number displayed.