MCCB shall be designed to be suitable for isolation function. When means are provided or specified by the manufacturer to lock the equipment in the open position, locking in that position shall only be possible when the main contacts are in the open position.
This shall be verified in accordance with IEC 60947-1 8.2.5 clause. Equipment shall be designed so that the actuator, front plate or cover are fitted to the equipment in a manner which ensures correct contact position indication and locking, if provided.
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