THREE PHASE DEMAGNETISER UNIT
Mhy Pro-Power Services Sdn Bhd (772150-W)
DV POWER - TESTING EQUIPMENT, Transformer Switchgear,
After a DC current test, such as a winding resistance measurement, the
magnetic core of a power or instrument transformer may be magnetized
(remanent magnetism). Also, when disconnecting a transformer from
service, some amount of magnetic flux trapped in the core could be
DV POWER - TESTING EQUIPMENT
The remanent magnetism can cause various problems such as erroneous
diagnostic electrical measurements on a transformer, or an inrush
current at start-up of power transformer, or incorrect operation of
protective relays due to magnetized CT cores.
To eliminate this source of potential problems, demagnetization should be performed.
When suspecting remanent magnetism, or when various test results, like
FRA or magnetization/excitation current, show possible remanency use the
DEM60 to perform fully automatic demagnetization.
Demagnetizing magnetic core of a transformer requires alternating
current applied with decreasing magnitude down to zero. The DEM60
provides this alternating current by internally changing the polarity of
a controlled DC current. During the demagnetization process the
instrument supplies current at decreasing magnitude for each step,
following a proprietary developed program.
, Transformer Switchgear
Contact Mhy Pro-Power Services Sdn Bhd (772150-W)
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