Setup Table Menu Features - Keysight X Series Measurement Manual

Disturbance Analyzer (Click) Measurements

Setup Table Menu Features

Setup Table Menu Features
Frequency
CISPR 14 requires that discontinuous disturbance measurements be made at 4
frequencies: 150kHz, 500kHz, 1.4 MHz and 30 MHz. The MXE allows you to select
these default frequencies or to enter a non-standard measurement frequency.
Terminal
CISPR 14 defines limits based on the terminals at which the measurements are made.
Table 1 in CISPR 14 defines the limits for continuous disturbance over frequency for
both mains and load terminals and for motors of varying power levels. The limits for
discontinuous disturbances (clicks) are based on these limits.
Limit
The limit used for the data analysis is a function of the nature and rate of the
measured discontinuous disturbances and the level of the continuous disturbances.
CISPR 14-1 defines the limit for a continuous disturbance (L) as a function of
frequency and measurement location (mains or terminal). This document also
defines a limit that can be used for discontinuous disturbances (Lq). Lq is relaxed
from L according to the number of clicks measured per minute, known as the click
rate N:
44 dB for N < 0.2
20 log (30/N) dB for 0.2<= N < 30
No relaxation for N>= 30
Selecting Auto Limit configures the MXE to autocouple the default continuous
disturbance limit values to the frequency and terminal selection. This will be the
starting point of the Lq calculation once N has been calculated during and after the
data collection. Selecting Man allows you to enter a specific limit value to be used as
a starting point from which to calculate a discontinuous disturbance limit based on
the characteristics of the measured signal.
Attenuation
The attenuation is set so that, in the worst case, an input signal with a Quasi-Peak
value equal to the maximum relaxed discontinuous disturbance limit will not
overload the receiver. If you know in advance that your input signals will be lower,
you can use a lower value of input attenuation.
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