Mitsubishi Electric Melsec Q Series User Manual page 122

9 Troubleshooting
9.3.4 Q&A about Connection
Q Does polarity exist in connection between a current sensor and the module?
Yes, it does.
Make connections so that secondary terminals of current sensor (k, l) and terminal symbols of
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module agree with each other.
If polarity is incorrect, the current value is measurable, but the electric power and the electrical
energy can not be measured correctly.
Q Are there any key points in avoiding errors in wiring?
Check polarity of current sensor on the primary current side.
Power supply side of the circuit is indicated as "K," and the load is indicated as "L." An arrow
indicates the direction from K to L.
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For a 3-wire circuit, check that the current sensor and the module are connected correctly for
the 1-side circuit and 3-side circuit.
Besides, check that voltage inputs are connected correctly among P1, P2, and P3.
Q
How do wires extend between a current sensor and the module?
Model EMU-CT***, EMU-CT***-A are extendable up to 50 m.
Model EMU2-CT5 is extendable up to 11 m, using together with extension cable. To extend the
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wire further, use the current transformer CW-5S(L) for split-type instrument in combination,
extending the secondary wiring on CW-5S(L) side.
9.3.5 Q&A about Setting
Q
Is the setting required?
At least, settings of phase wires, primary current and primary voltage are required. Specify
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settings in accordance with a circuit to be connected.
If a primary current setting value is different from that of rated current on a connected
Q
current sensor, does it cause a breakdown?
It does not cause breakdown or burning. However, measurement values will be totally
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incorrect.
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QE81WH