Panasonic KW1M Eco-Power METER, User Manual

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KW1M Eco
－
POWER METER
50
Chapter 10 Q&A
■ Hardware
Q1 I’d like to measure by Eco-POWER METER.
Measured load is 50 to 60A in normal operation. But the inrush current is 130 to 140 A.
Which CT is selected? (100A or 250A)
A1 Select 100ACT.
Stable current more than 1 second is necessary to measure. The inrush current seems to be a
few ms, therefore it can’t measure it. In case there is current over 1 second (inrush current), it
measures it and select 250A CT.
Q2 Current and voltage are displayed. But it can’t measure an electric power.
A2
・
Do you install CT to the correct position and correct direction?
CT has directions.
Install CT according to the direction marked. From power supply side (K) to load side (L).
・ Do you wire measurement voltage input correctly?
When phases of voltage and current are not matched, it can’t measure correctly.
Please check the wiring.
Q3 How long do I extend CT cable?
A3 You can extend up to about 10 m with cable of AWG#22 or more.
We can’t guarantee the specifications if you extend more than 10m.
Q4 How do you guarantee the accuracy of measurement with low current range?
A4 Up to 10% for CT rating.
In case of CT50A, for an electric power with current 5A or more, the accuracy is ±2.5%.
(For PF=1)