Fluke OMNIFiber, Руководство пользователя

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OMNIS
CANNER
User Guide
6 - 10
Impulse Noise
Noise is undesirable electrical energy that falls within the typical
network frequency bands of operation (generally 1-20 Mhz). It inter-
feres with a network’s ability to transmit data reliably. Noise sources
may include AC transmission lines, fluorescent light fixtures, industrial
equipment, elevators, etc. Noise problems also occur when other wire
pairs in the same sheath are used for non-LAN applications.
Testing for noise involves turning off all LAN devices and measuring for
background electrical activity in the cabling. Often, noise problems can
be corrected by moving the cable away from the source or by remov-
ing the source itself.
Impulse Noise counts the impulses detected on a given pair
Select Impulse Noise to open the IMPULSE
NOISE screen. The current date and time is
shown in the upper left. The monitored pair is
shown in the upper right.
Impulses/sec indicates the number of wide band
impulses that exceed 30 mv peak-to-peak that
were detected in the last 1second interval.
Total Impulses indicates the total number of impulses detected since
noise monitoring was started.
Elapsed Time indicates the time since the test was started.
Press (Pair) to clear the current log and monitor impulse noise
on another pair.
Press (Detail) to open the LOG screen.
OMNIS
CANNER
keeps a log during impulse noise
monitoring. The log represents the seven largest
impulse noise counts detected and the date and
times at which they occurred.
Press ESC to exit the LOG screen.
Press ESC to exit the IMPULSE NOISE screen.