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Entry type: FAQ Entry ID: 21656588, Entry date: 05/20/2014

General: Is it mandatory to switch all phases of a 3-phase load?

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Is it allowed to switch only 2 phases of a 3-phase load?




For operational duty it is permissible to switch only 2 phases of a 3-phase load (DIN VDE 0100 Teil 460 § 465.1.2  /  HD 384.4.46 S2).
Naturally this is applicable to delta-connected 3-phase load only or star-connected 3-phase load with a star point that is not grounded or connected to neutral.


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