Atec OMICRON-MPD-500 - Manual (Page 4)

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Advantages of fiber-optic communication
The whole MPD family utilizes the "point of PD measurement",
processing and digitizing in close proximity to the coupling
device as shown below. The digitized signal is transferred to
the operator's control room using optical communication. This
principle minimizes the effective ground loop and the influence
of external interferences resulting in a significantly reduced
background noise level.
Electromagnetic disturbances of nearby HV equipment have
no influence on optical fibers, therefore cable routing is fast
and easy, without special precautions. Safety comes first - the
fully galvanic isolation between "point of PD measurement" and
control room sets new standards of operational safety even
during a breakdown of the test object.
Very long fiber-optic connections may be used without
degrading the instrument's performance - The distance between
PD detection and operator could get up to 2 km / 1.2 miles.
Excellent Noise Suppression
There are many sources of interference which can complicate the measurement of partial discharges. The MPD 500 provides effective
features for reducing or eliminating the effect of these disturbances, making the measurements more reliable and accurate.
Active noise suppression
The center frequency can comfortably be adjusted via slider from
0 MHz to 2.5 MHz. Together with three selectable bandwidths,
the MPD 500 can be tuned away from noise to a more "quiet"
frequency range, focusing optimally on the test object's
PD signals.
Simply use the mouse to enable an unlimited number of
phase amplitude gates for effective suppression of phase-fixed
disturbances.
Battery-powered portability
In addition to the advanced "point of measurement" principle,
even further circuit sensitivity can be realized by eliminating noise
from the mains that power the MPD 500. Every unit is supplied
with a battery attachment, that has the capability of powering
the system for up to 20 hours of continuous operation.
Conventional PD detection
Innovative PD detection with the MPD 500
Device under test
Coupling
capacitor
Device under test
Coupling
capacitor
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Ground loop
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Interference
Point of PD
measurement
5 m ... 50 m / 16 ft ... 164 ft measurement cable
MPD 500
and MPP 600
Optical fiber
up to 2 km
Point of PD
measurement
~ 0.3 m / 1 ft
Coupling device
Coupling device
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