Installation Of Dedicated Ct, Zct - Omron KE1 User Manual

Chapter 2 Preparation
2.3

Installation of dedicated CT, ZCT

The dedicated CT, ZCT is divided into the two types: split type and panel fixed (through) type.
[Common]
 Measurement with single-phase 2-wire requires one dedicated CT, measurement with
single-phase 3-wire or 3-phase 3-wire requires two dedicated CTs, and measurement with
3-phase 4-wire requires three dedicated CTs.
 The dedicated ZCT can be used for the measurement in single-phase 2-wire, single-phase
3-wire, 3-phase 3-wire, and 3-phase 4-wire.
 Use of dedicated CTs in a circuit requires all the CTs to have the same standard.
 The standard of the dedicated CTs to be used should match the settings of the dedicated
CT of Model KE1.
 A dedicated CT has its polarity. Carry out wiring correctly between (K) and (L).
For terminal positions, refer to Page 2-16 and later.
 Before making connections, confirm the directions of power supply side (K) and load side
(L). Wrong direction prevents correct measurements.
 Securely close the terminal cover on the secondary side of dedicated CT.
 Do not ground the dedicated CT. Doing so causes a failure.
 Electric shocks may occur.
For the primary side wire to be clamped in CT, be sure to use a covered electric wire of 600
V or more in basic insulation.
When using a conductive object, such as bus bar, for clamping, ensure the basic insulation
at least by, e.g., covering with an insulator.
 Avoid direct clamping in a line of 600 VAC or more.
[Split type]
 Open the hook for the split/fixed type and clamp each phase. After clamping, securely
perform fitting until a clicking sound is heard.
[Panel fixing (through) type]
 Securely fix the dedicated CT, ZCT to the panel, etc.
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