True-RMS Multimeter
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Introduction
Overview
The Protek D705/D705T are true-RMS multimeters and battery-powered with a 5000-counts, 25
segments bar graph. These multimeters are fully compatible to CAT III and CAT IV IEC 61010
standards, which denes four overvoltage categories(CAT I to IV) based on the magnitude of danger
from transient impulses.
Measurement Category I:
This category is for measurements of voltages from specially protected secondary circuits. Such
voltage measurements include signal levels, special equipment, limited-energy parts of equipment,
circuits powered by regulated low-voltage sources, and electronics.
Measurement Category II:
This category refers to local-level electrical distribution, such as that provided by a standard wall
outlet or plug in loads (for example, 115 AC voltage for U.S. or 200 AC voltage for Europe). Examples
of Measurement Category II are measurements performed on household appliances, portable tools,
and similar modules.
Measurement Category III:
This category refers to measurements on hard-wired equipment in xed installations, distribution
boards, and circuit breakers. Other examples are wiring, including cables, bus bars, junction boxes,