Panasonic KW4M User Manual page 25

◇To connect CT with secondary 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 (AKW4801), 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
◇How to attach the Current Transformer (CT)
・One current transformer (CT) is required to measure a single-phase, two-wire system. Two CTs are
required to measure a single-phase, three-wire system or three-phase, three-wire system. Using 2
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.
・For the dedicated CT (AKW4801,4802,4803,4804), 'k' is the white wire and ' l ' is the black wire.
・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 0.75mm
more cross section under the environment without noise at all. Please use the thick cable as much as
possible.
･If there is some distortion by harmonic or waveform, it may not measure correctly. Please check with
the actual system before adopting it.
Power supply
Breaker
Secondary current
K
5A
Commercial CT
L
Power supply
Breaker
Secondary current
K
5A
Commercial CT
L
Ammeter etc.
Eco-POWER METER
L K
Dedicated CT (AKW4801）
Eco-POWER METER
L K
Dedicated CT (AKW4801）
2
or
19