In recent years the number of manufacturers producing IP54 standard variable speed drives has increased quite substantially. However in reviewing many of these products I have found the cooling fans (generally fitted in some sort of ventilation chamber and exposed to the elements) to have and IP42 rating only.

How is it possible for the manufacturers of such drives to give their product an IP54 rating? Are these just other examples of marketing people going mad? ;p;

Regards,
GGOSS

It is actually quite easy!! It does not depend on the individual components, but the total package. This will determine the overall IP rating ie. a PCB will have an IP 00 rating, but put it in a drive and the package will have a higher rating.
These manufacturers must pass some pretty extensive tests to achieve the IP 54 (or NEMA equivalent) rating.

Hello GGOSS

With marketing license you can make many claims. Some of those fns, particularly the low voltage DC, are very susceptable to any moisture and the electronics quickly rot away. Particulary in pumping situations where there is Chlorine or H2S present. If you pay a lot more, you can get fans with conformal coated electronics and these will last a lot longer.
I agree with you, the IP rating should really apply to the weakest link. If the fan is exposed and it is only IP42 or less, then they should not claim a higher IP rating for the unit. - it certainly happens however.
Best regards,

Many thanks Marke & theDOG,

I spoke to a drives product manufacturer about this very subject recently and was amazed by his comments.

The products he manufactures are rated to IP54 although the cooling fans used are rated to IP42 ie much the same as that described in my original post.

His products were summitted for testing to IP54 and were approved although the fans are not protected against the elements. He claims approval to IP54 was achieved because the tests are conducted over a short period of time, during which fan failure is unlikely.

Are the tests so simplistic that individual components are not fully eveluated or have I missed something here?

Please advise.
GGOSS