Measurement Categories
These definitions were derived from the international safety standard for insula-
tion coordination as it applies to measurement, control, and laboratory equipment.
These measurement categories are explained in more detail by the International
Electrotechnical Commission; refer to either of their publications: IEC 61010-1 or
IEC 60664.
Measurement Category II
Local level. Appliances, portable equipment, and the circuits they are plugged into.
Some examples include light fixtures, televisions, and long branch circuits.
Measurement Category III
Distribution level. Permanently installed machines and the circuits they are hard-wired
to. Some examples include conveyor systems and the main circuit breaker panels of a
building's electrical system.
Measurement Category IV
Primary supply level. Overhead lines and other cable systems. Some examples include
cables, meters, transformers, and other exterior equipment owned by the power utility.
Statement of Conformity
Greenlee Textron Inc. is certified in accordance with ISO 9001 (2000) for our Quality
Management Systems.
The instrument enclosed has been checked and/or calibrated using equipment that is
traceable to the National Institute for Standards and Technology (NIST).
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