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Safety Notes
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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 instrument in an
environment designated with a higher-
numbered category than that for which the
instrument is rated could result in a severe
accident, and must be carefully avoided.
Never use a CAT I measuring instrument in
CAT II, III, or IV environments.
The measurement categories comply with the
Overvoltage Categories of the IEC60664
Standards.