NI CF-6004 U
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ide and Specification
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withstand voltage levels that commonly occur in electrical distribution systems. The following
is a description of measurement categories:
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Measurement Category I is for measurements performed on circuits not directly connected
to the electrical distribution system referred to as MAINS
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voltage. 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.
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Measurement Category II is for measurements performed on circuits directly connected to
the electrical distribution system. This category refers to local-level electrical distribution,
such as that provided by a standard wall outlet (for example, 115 V for U.S. or 230 V for
Europe). Examples of Measurement Category II are measurements performed on
household appliances, portable tools, and similar devices.
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Measurement Category III is for measurements performed in the building installation at the
distribution level. This category refers to measurements on hard-wired equipment such as
equipment in fixed installations, distribution boards, and circuit breakers. Other examples
are wiring, including cables, bus-bars, junction boxes, switches, socket-outlets in the fixed
installation, and stationary motors with permanent connections to fixed installations.
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Measurement Category IV is for measurements performed at the primary electrical supply
installation (<1,000 V). Examples include electricity meters and measurements on primary
overcurrent protection devices and on ripple control units.
Electromagnetic Compatibility G
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This product was tested and complies with the regulatory requirements and limits for
electromagnetic compatibility (EMC) stated in the product specifications. These requirements
and limits provide reasonable protection against harmful interference when the product is
operated in the intended operational electromagnetic environment.
This product is intended for use in industrial locations. However, harmful interference may
occur in some installations, when the product is connected to a peripheral device or test object,
or if the product is used in residential or commercial areas. To minimize interference with radio
and television reception and prevent unacceptable performance degradation, install and use this
product in strict accordance with the instructions in the product documentation.
Furthermore, any modifications to the product not expressly approved by National Instruments
could void your authority to operate it under your local regulatory rules.
Caution
To ensure the specified EMC performance, operate this product only with
shielded cables and accessories.
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Working Voltage is the highest rms value of an AC or DC voltage that can occur across any particular
insulation.
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MAINS is defined as a hazardous live electrical supply system that powers equipment. Suitably rated
measuring circuits may be connected to the MAINS for measuring purposes.
