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2.
Installation and wiring
2.2 Wiring the CTs
You can connect up to a maximum of 4 generic CTs to this unit (
21). The number of CTs used depends on the phase and wire type
of the power source being monitored. The following table shows the phase and wire types and the CTs to use for each. For example,
use CT1 when measuring only one 1-phase 2-wire circuit. Further, when measuring two 1-phase 3-wire circuits, use CT1 and CT2 for
circuit A and use CT3 and CT4 for circuit C.
The layout of CT input terminals is as follows.
The following table shows the phase and wire types and the CT allocations for each measuring circuits.
• Connect the CT cables for CT1/CT2/CT3/CT4 to the terminals on the main unit that are labeled CT1/CT2/CT3/CT4.
• For details about how to wire the CTs, refer to the manual of the CTs you are using.
Phase and wire
type
Abbreviations
for phase
and
wire types
Measuring circuits
Circuit A
Circuit B
Circuit C
Circuit D
3-phase 4-wire
3P4W
CT1, CT2, CT3
̶
̶
̶
1-phase 2-wire
1P2W
CT1
CT2
CT3
CT4
1-phase 3-wire
1P3W
CT1, CT2
̶
CT3, CT4
̶
3-phase 3-wire
3P3W
CT1, CT2
̶
CT3, CT4
̶
1-phase 2-wire
voltage selected
1P2W2
CT1
CT2
CT3
CT4
1-phase 3-wire
composite
1P3W2
CT1, CT2
̶
CT3
CT4
Important
• Do not try to connect or disconnect CTs or CT cables during measurement or while the power of this
product is on. There is a danger of electric shock. Furthermore, this may cause this unit and the CT to
malfunction.
• For wiring to the CT input terminals, use 18 to 14 AWG (cross section surface area of 0.75 to 2.0mm
2
)
electrical wire.
• Use ferrule terminals suitable for the wire diameter to connect to the CT input terminals.
• The recommended torque for the 3mm screws is between 0.5 and 0.6Nm. Make sure the ferrule terminal
is pushed all the way in and tightened firmly. After fixing the wiring in place, pull gently to confirm that
the wiring is fixed firmly.
CT input terminals
Wiring
8mm
Under 2.7mm
Under
2.0mm
M3 screw
CT input terminals
