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Module 5

Various forms of Enclosures

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Various forms of Enclosures Internal separation of ASSEMBLIES by barriers or partitions

One or more of the following conditions can be attained by dividing ASSEMBLIES by means of -- A) Partitions or barriers (metallic or non-metallic) into separate compartments or enclosed protected spaces:

– protection against contact with hazardous parts belonging to the adjacent functional units. The degree of protection shall be at least IPXXB;

– protection against the passage of solid foreign bodies from one unit of an ASSEMBLY to an adjacent unit. The degree of protection shall be at least IP2X.

Unless otherwise stated by the manufacturer, both conditions shall apply.

NOTE The degree of protection IP2X covers the degree of protection IPXXB.

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Forms : separations within an assembly

Definitions

Form 2bContents

Form 2aForm 1Form 1 : no separation within the enclosure.

Form 2a : the functional units areseparated from busbars, but not theterminals

Form 2b : the functional units and terminals are separated from the busbars. The terminalsare not separated from each other.

Form 2: Separation of busbarsfrom the functional units

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Various forms of Enclosures.

Form 3a

Form 3b

Form 3a : the functional units are separated from each other and from the busbars , but not the terminals.

Form 3b : the functional units are separated from each other and from the busbars. Terminals are separated from

busbars, but are not separated from each other

Form 3: Separation of busbars from the functional units and separation of all functional units, one from another, except at their output terminals

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Forms of Enclosures

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Form 4a

Form 4b

Form 4a : the functional units are separated from each other and from the busbars . Terminals which are in the same compartment as the associated functional unit are separated from each other

Form 4b : the functional units are separated from each other and from the busbars. Terminals are separated from each other and from the functional units.

Form 4: As for Form 3, but including separation of the outgoing terminals of all functional units, one from another

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Module 5

Various forms of Enclosures