IP vs NEMA ?


Thread Starter

Mark Hill

Hi all;

Can someone point me to a site that explains and compares IP and NEMA ?

Mark Hill

Ranjan Acharya

I am assuming that you are referring to IEC 60529 / IEC 529 - Ingress Protection standard for electrical enclosures and devices – refer to NEMA 250 for purely North American version. Also referred to as EN 60529.

Enclosures and devices receive a two-digit code; the first digit specifies the protection against solid bodies and the second digit specifies protection against liquids.

NEMA 250 ratings exceed equivalent IP ratings since additional protection such as coolants, oil, corrosion and hail is often included in any NEMA rating – conversion is always approximate and IP should not be converted to NEMA.

For example, NEMA 4 enclosures can be used indoors or outdoors and offer protection to persons using the cabinets against the (according to a web site I read) effects of: falling and windblown particles of dirt, precipitation and water directed under pressure. A NEMA 4 cabinet can also withstand the formation of ice. NEMA 4X extends NEMA 4 to include some protection from corrosion. Approximately equivalent to IP55/IP56/IP66 (depending on whose web site you read).

I never like comparing the two. The end-user should make up their mind and either use all IP or all NEMA. There is no good way of going back and forth, so you should not try. Different enclosure manufacturers list different IP equivalents for the same NEMA rating, depending on the phase of the moon I suppose.

There is not direct correspondence but the Hoffman Enclosure catalog gives a good explanation. Their web site has the information under standards - ratings and classifications at -

Bill Mostia::

William(Bill) L. Mostia, Jr. P.E.
exida.com, LLC
Worldwide excellence in dependable automation
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Thanks Ranjan;

My intention is to purchase enclosures manufactured in Europe that are rated IP. I'd like some idea of the NEMA equivalent. Not exact details, just approximations

The Hoffman link provided by Bill Mostia and Craig Simon ( "http://www.hoffmanonline.com/Technical_Info/":http://www.hoffmanonline.com/Technical_Info/ ) provides useful information, but the link to
"http://www.bray.com/bulletins/misc/iprating.html":http://www.bray.com/bulletins/misc/iprating.html provided by "Anonymous"
is a good place to see these comparisons.

Thanks All !!

Mark Hill
There is no one-to-one comparison, that being said this is a real world problem. Here is a link to Phoenix terminal block site pdfs which gives some guide lines and the second link is to NEMA’s “A Brief Comparison of NEMA 250 and IEC 60529”.



The one place that I have a different opinion than the list is NEMA-4X. The Phoenix chart show IP66 which will definitely work, but IP66 is suitable for submersion. I use IP65 which will is suitable for water spray. The difference between the IP and NEMA test is the size of the nozzle and the flow rates. So if you review the NEMA’s article you can make up your own mind.

Rasam Syamsudin

Dear Hill,

If you have Standard Practice API 14FZ, please read Section 6.11 Electrical Enclosure on page 56 to 60. Maybe this standard can help you.


Loren D., App. Eng.

there is no reference to IP65 in the chart on this link. I see numerous internet pages that say that IP's equivalent to Nema 4 is IP65... not IP56. 56, to me, does not seem comparable, as 65 would. Comments?