4
__________________________________________________
_____________________________________________
CAT I:
Secondary electrical circuits connected
to an AC electrical outlet through a
transformer or similar device.
CAT II:
Primary electrical circuits in equipment
connected to an AC electrical outlet by a
power cord (portable tools, household
appliances, etc.)
CAT III:
Primary electrical circuits of heavy
equipment (fixed installations) connected
directly to the distribution panel, and
feeders from the distribution panel to
outlets.
CAT IV: The circuit from the service drop to the
service entrance, and to the power
meter and primary overcurrent protection
device (distribution panel).
Measurement categories (Overvoltage categories)
This product complies with CATII (600V), CATIII
(300V) safety requirements.To ensure safe
operation of measurement products, IEC 61010
establishes safety standards for various
electrical environments, categorized as CAT I to
CAT IV, and called measurement categories.
These are defined as follows.
Higher-numbered categories correspond to
electrical environments with greater momentary
energy. So a measurement device designed for
CAT III environments can endure greater
momentary energy than a device designed for
CAT II. Using a measurement product in an
environment designated with a higher-numbered
category than that for which the product is rated
could result in a severe accident, and must be
carefully avoided.Never use a CAT I measuring
product in CAT II, III, or IV environments.