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Entry type: FAQ Entry ID: 109738389, Entry date: 06/15/2016

N125_2x KNX Power Supply Unit – suitable circuit breaker

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Which fuse is required to protect the KNX Power supply unit N 125/_2



On the input side it´s not necessary to use an external protection for the device protection of the KNX Power supply unit. However, normative regulations determine that it must be possible to disconnect the power supply from the supply network via a separate external unit. For this purpose, e.g. a primary-sided circuit breaker is suitable.


Therefore, any circuit breaker serves merely as a cable protection in this setup and therefore has to be selected according to the cable cross section. Additionally, in combination with decentrally installed devices the cable installation shall be considered in the selection of the suitable circuit breaker.

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