Honeywell RMA 3000, User Manual

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Release 1 34-ST-25-19 RMA 3000 Remote Meter Assemblies User Manual 43
6/04
NEMA and IEC
Recognition
The NEMA (National Electrical Manufacturer’s Association) enclosure
classifications are recognized in the US. The IEC Publication 529 Classifications are
recognized throughout Europe and those parts of the world that use the IEC standards
as a basis for product certifications. The following paragraphs provide a discussion of
the Comparison Between NEMA Enclosure Type Numbers and IEC Enclosure
Classification Designations.
IEC Classifications
IEC Publication 529, Classification of Degrees of Protection Provided by Enclosures,
provides a system for specifying the enclosures of electrical equipment on the basis of
the degree of protection provided by the enclosure. IEC 529 does not specify degrees
of protection against mechanical damage of equipment, risk of explosion, or
conditions such as moisture (produced for example by condensation), corrosive
vapors, fungus, or vermin.
NEMA Standards
NEMA Standards Publication 250, Enclosures for Electrical Equipment (1000 Volts
Maximum), does test for environmental conditions such as corrosion, rust, icing, oil,
and coolants. For this reason, and because the tests and evaluations for other
characteristics are not identical, the IEC enclosure classification designations cannot
be exactly equated with NEMA enclosure type numbers.
IEC Designations
Basically, the IEC designation consists of the letters IP followed by two numerals.
The first characteristic numeral indicates the degree of protection provided by the
enclosure with respect to persons and solid foreign objects entering the enclosure. The
second characteristic numeral indicates the degree of protection provided by the
enclosure with respect to the harmful ingress of water.