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What's recommend CT connections & Current Signal connections for Power Meter and Current Transformer?

The power meter accepts up to 6 A AC RMS per channel directly. Above that, a Current Transformer must be interposed to scale down the current.
There are three pairs of current input terminals marked A1, A2 and A3. Each pair of input terminal is labeled as (S1, S2) and has an arrow indicating the direction of current flow. For proper measurements, the phase identification as well as the polarity of the current signals must be correct. The forward flow (import by consumer) current direction must be into the S1 terminal and the exit from the S2 terminal. Please maintain the correct sequence and polarity to avoid wrong readings.
Any unused current input terminals (e.g. A2 (S1, S2) for Delta) must be shorted together. The shorted terminals do not need to be grounded.
Install the wiring for the current circuit at 480 VAC insulation as a minimum. The cable connection should be rated for 7.5 A or greater and have a cross-sectional area of 2.5 mm2 minimum.

CT Connections
Mount the current transformers (CTs) as close as possible to the power meter for best accuracy. The following table illustrates the maximum recommended distances for various CT sizes, assuming the connection is via 2.5 mm2 cable.
Table: 5-5: CT Size and Maximum Distance

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