Mr. Görner, what exactly do DIN 12944 protection classes C1 to C5 signify?
Raphael Görner: DIN 12944 deals solely with the corrosion protection of steel structures. This standard makes no reference to enclosures. It just relates to steel products with a relatively high material thickness. The standard doesn’t cover topics such as coating or materials such as aluminium or stainless steel either – just the corrosion protection of components used for applications such as fire escapes, photovoltaic installations, etc.
Why is the standard nonetheless applied to enclosures?
This happens when plant engineering companies install the enclosures close to such steel structures and only know the corrosion protection requirements for these steel structures. In more than a few cases, when there isn’t any information stating otherwise, the DIN 12944 corrosion protection requirements are extended to the enclosures.
What is the difference between the protection classes?
In terms of how the protection classes apply to enclosures, we can only refer to the salt spray mist test – from protection class C3-L, at 120 hours, through to protection class C5-H, at 1,440 hours.
What do the protection classes signify in terms of enclosure requirements?
Even though the standard does not apply to enclosures, Rittal can indicate what level of corrosion protection surfaces and materials offer, meaning our customers can compare this with their requirements. For example, the standard coating of our sheet steel enclosures passes a 120-hour salt spray mist test corresponding to class C3-L, while zinc-magnesium enclosures successfully complete 720-hour tests corresponding to C4-H and C5-M. In the future, various standard dimensions of the AX compact enclosures and the VX enclosures will have a surface coating that meets the requirements for protection class C4-H to DIN EN ISO 12944.
