no (internal) connection (pin) (NC)

A terminal that has no internal connection and that can be used as a support for external wiring without disturbing the function of the device, provided that the voltage applied to this terminal (by means of the wiring) does not exceed the highest supply voltage rating of the circuit.

NOTE 1 If higher voltages are acceptable, this should be stated.

NOTE 2 The IEC equivalent term is "blank terminal"; nevertheless, the IEC abbreviation is "NC".

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