The DEM60C is designed for demagnetizing the core of power, instrument or current transformer. It can be used to eliminate the source of potential problems such as, erroneous diagnostic, inaccurate measurements on a transformer, inrush current at a start-up of power transformer, incorrect operation of protective relays, which remnant magnetism can create.
The DEM60C provides an alternating current, needed for demagnetizing the transformers’ core, by internally changing the polarity of a controlled DC current. During the demagnetization process the instrument supplies a current at decreasing magnitude for each step. This is the UNIQUE device on the market.
DEM60C is a three-phase, fully automatic test set specially designed for transformer demagnetization. Transformer magnetic core demagnetization requires alternating current applied with magnitude decreasing to zero. DEM60C provides this alternating current by internally changing the polarity of a controlled DC current. During the demagnetization process the instrument supplies the current at decreasing magnitude for each step, following a proprietary software solution. DEM60C is based on a state of the art technology, using the most advanced technique available today. The test set can be used to demagnetize single-phase and three-phase transformers.
For a three-phase operation, the instrument is connected to all the three phases of a transformer to be demagnetized. If specific vector diagrams are selected for different types of transformers, DEM60C will run a specific demagnetization procedure for each transformer type without a need to switch the test hookup cables.
Fullyautomatic demagnetization
Demagnetization currents 5 mA – 60 A DC
Demagnetization process graph
Automatic discharging circuit
Lightweight – 13,1 kg
Eliminating Problems Created by Remanent Magnetism 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 present. The remanent magnetism can cause various problems such as erroneous diagnostics, inaccurate measurements on a transformer, an inrush current at a start-up of power transformer, or an incorrect operation of protective relays due to magnetized CT cores. To eliminate this source of potential problems, demagnetization should be performed.
Discharging Circuit
Injection of current and discharging energy from the inductance are both automatically regulated. During and after the operation, an intrinsically safe discharge circuit with an indicator rapidly dissipates the stored magnetic energy. The discharging circuit is independent of power supply, which means it will dissipate the stored energy even in case DEM60C power supply is accidentally broken.
Connection: according to IEC/EN60320-1;UL498, CSA 22.2
Mains supply: 90 – 264 V AC
Frequency: 50/60 Hz
Input power: 2250 VA
Fuse: 15 A / 250 V, type F, but not user replaceable
Test current 5 mA – 60 A DC
Dimensions (W x H x D):480 x 190 x 385 mm, 18.9 x 7.48 x 15.16 in
Weight: 13,1 kg / 28.8 lbs
