Differential Mode Range And Common Mode Range; Iec/En 61010-031 Definitions - Teledyne Lecroy HVD3000 Series Operator's Manual

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Differential Mode Range and Common Mode Range

Differential Mode range is the maximum signal that can be applied between the + and - inputs
without overloading the amplifier, which otherwise would result in clipping or distorting of the
waveform measured by the oscilloscope.
The Common Mode Range is the maximum voltage with respect to earth ground that can be
applied to either input. Exceeding the common mode range can result in unpredictable
measurements. Because the Common Mode signal is normally rejected, and not displayed on
the oscilloscope, be careful to avoid accidentally exceeding the common mode range.

IEC/EN 61010-031 Definitions

IEC/EN 61010-031/A1:2008
Measurement Category III (CAT III) applies to test and measuring circuits connected to the
distribution part of the building's low-voltage mains installation.
Measurement Category II (CAT II) applies to test and measuring circuits connected directly to
utilization points (socket outlets and similar points) of the low-voltage mains installation.
Measurement Category I (CAT I) applies to test and measurement circuits that are not intended
to be directly connected to the mains supply.
Pollution Degree 2 refers to an operating environment where normally only dry non-conductive
pollution occurs. Conductivity caused by temporary condensation should be expected.
IEC/EN 61010-031:2015
Measurement Category III (CAT III) applies to test and measuring circuits connected to the
distribution part of the building's low-voltage mains installation.
Measurement Category II (CAT II) applies to test and measuring circuits connected directly to
utilization points (socket outlets and similar points) of the low-voltage mains installation.
No Rated Measurement Category (O) applies to other circuits that are not directly connected to
the mains supply.
NOTE: The 2015 version of the standard eliminates the Measurement Category I (CAT I) and
creates a new rating, "O", which refers to "Other circuits that are not directly connected to the
mains". Products that conformed to Measurement Category I in the 2008 version of the
standard may now be classified as "O".
Pollution Degree 2 refers to an operating environment where normally only dry non-conductive
pollution occurs. Conductivity caused by temporary condensation should be expected.
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