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IM 760301-01E
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App
Index
Measurement Conditions
Explanation
Set the VT ratio when applying the output from the secondary side to the voltage input
terminal.. Then, set the voltage range according to the maximum value of the VT output
(see section 4.3). In addition, set the CT ratio (or the transformation ratio of the current
sensor that outputs current) when applying the secondary output of the CT or clamp-type
current sensor that outputs current to the current input terminal. Then, set the current
range according to the maximum value of the current sensor output. For details, see
section 2.3.
• Turning ON/OFF the Scaling Function
You can select whether to multiply the applicable measurement function by the VT
ratio, CT ratio, or power coefficient. When reading the measured value directly using
VT or CT (or current sensor), select ON. The SCALING key illuminates when ON is
selected.
Applicable measurement function:
Voltage U, current I, power (P, S, and Q),
maximum and minimum voltages (U+pk and U-
pk), and maximum and minimum currents (I+pk
and I-pk)
• ON:
The measurement functions above are multiplied by the VT ratio, CT ratio,
and power factor.
• OFF: The measurement functions above are not multiplied by the VT ratio, CT
ratio, and power factor. The output values of the VT and CT are displayed
directly as numeric data.
• Setting the VT Ratio (VT)
The VT ratio can be set in the range of 0.0001 to 99999.9999.
• Setting the CT Ratio (CT)
The CT ratio can be set in the range of 0.0001 to 99999.9999.
• Setting the Power Factor (SF (Scaling Factor))
The power coefficient (SF) can be set in the range of 0.0001 to 99999.9999.
Note
•
If the result of multiplying the VT ratio, CT ratio, or power coefficient (scaling factor) to the
measured value exceeds 9999.99M, the display frame of the numeric data will display [-OF-].
•
For the list of the VT, CT, and power factor of all input elements, see section 3.17, “Displaying
the Setup Parameter List.” When the scaling function is OFF, VT, CT, and power factor are
displayed as 1.0000 in the list.
•
To correctly compute the power and efficiency of
Σ
functions, set the power factors of all
elements so that all power units used in the computation are the same. For example, the
efficiency over elements or wiring units with mixed power units of W (watt) and J (joule)
cannot be computed correctly. Unify the power unit to W or J.
4.5 Setting the Scaling Function When Using VT/CT