Panasonic AKW1110, User Manual

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KW1M Eco
－
POWER METER
28
6.4 How to attach the Current Transformer (CT)
・
Using all CTs should be the same.
・ When connecting CT, connect the secondary side to the terminal of the main unit first, and after that
wire the primary side to a load electric wire. The CT has polarity. Wire correctly according to the K and
L marks.
・ Check beforehand that the thickness of the electric wire is smaller than the through-hole of the CT. If
you use a CT that separates at the bottom, make sure it is closed securely once the wire is in place; if
not an error in measurement will occur.
・
When CT
’
s cable is extended, it is possible to extend up to about 10m with the cable of AWG#22 or
more cross section under the environment without noise at all. Please use the thick cable as much as
possible.
◆
To connect CT with secondary side current 5A
How to connect the unit to measure by combination with existing commercial CT
(1) Select 5A at CT type setting mode (CT-T).
(2) Set the primary current of measured commercial CT (secondary current 5A) at primary side
current of CT setting mode (CT-1).
< ex > If the measured CT is 400A/5A, set to ”400”.
(3) Clamp the dedicated CT for 5A (AKW4801C), which is connected to the main unit first, to
secondary side of the commercial CT. CT direction (K → L) should be set for the commercial CT
direction.
(Connection example)
With Ammeter etc.
Without Ammeter
Secondary current
5A
Breaker
Dedicated CT (For 5A)
AKW4801C
Ammeter etc.
Power supply
Commercial CT
L K
K
L
Eco-POWER
METER
Load
Secondary current
5A
Breaker
Power supply
Commercial CT
K
L
Load
Dedicated CT (For 5A)
AKW4801C
L K
Eco-POWER
METER
Shorted or resistor less than 0.1
Ω