1. Digital Current Transformer Reporter
DCT-2000
DCT-2000

3. CT Purpose
To accurately reduce the primary current to a value suitable for relays and meters. (5 or 1 amps).
Provide isolation from the high voltage system.

4. Testing and Verification
NETA -National Electrical Testing Association Recommendations:
Perform polarity test.
Perform ratio-verification test using voltage or current method
Perform an excitation test.
Measure circuit burden.

5. Ratio and Polarity
Ratio must be verified so that relays and meters will operate and indicate correctly.
Polarity must be correct if relays are to “look” in the correct direction, and for meters to indicate correctly.

6. Ratio and Polarity Errors
Taps may have been connected to the wrong terminals or may have been labeled incorrectly.
Wrong number of turns on CT secondary.
Shorted turns.
Wrong polarity markings.

7. Saturation Voltage
Excitation characteristics and saturation voltage must be known to verify that the CT will perform as required by providing required output voltage during fault conditions.

8. Excitation of Multi-ratio CT

9. Typical test circuit of variac volt and amp meters

10. Time Study
Time to test 5-tap CT (ten ratios and one excitation curve) with older style equipment for:
Ratio
Polarity and phase-angle
Excitation and Saturation
Winding Resistance
Insulation resistance
Time=52 minutes
With DCT-2000x5, time < 5 minutes

11. Product available in two models:
Adwel solution
The DCT-2000 offers the most advanced features in automated multi-ratio CT testing.
Product available in two models:
DCT-2000x2
DCT-2000x5 – Test Plan Driven

12. Automated testing of one winding of a CT for:
Key Features of DCT-2000x2
Automated testing of one winding of a CT for:
Ratio
Polarity and phase-angle
Excitation and Saturation
Winding Resistance
Insulation resistance

13. DCT-2000x2

14. Test circuit of x2.

15. Save test and go the next winding
Testing Steps of x2
Enter windings to be tested
Check-off tests to be preformed
Set a voltage limit
Press test
Observe progress
Save test and go the next winding

16. Test Screen for x2 Configured Note: x2 does not have test plan

17. Automatically tests up to 5 taps with operator intervention.
Key Features of x5
Same as x2 plus:
Automatically tests up to 5 taps with operator intervention.
Test plan driven.
Provides the ultimate in CT testing productivity.

18. DCT-2000x5

19. Test circuit of x5.

20. Test Screen Driven from the Test Plan

21. Test Plan

22. The following screens are common to DCT-2000x2 and DCT-2000x5.

23. CT Info Screen

24. Extra Results Details

25. Extra Results Details

26. Full Graph Screen

27. Excitation Table Screen

28. File Manager

29. Burden Mode up to 20 amps

30. Other Features
Saturation voltage (knee point) is calculated.
Winding resistance is measured
Insulation resistance is measured
Full 75 key keyboard
Store 200 files.
Store 140 test plans in x5.

31. Other Features
Up to 2000 Vac output
Up to 2 amps output
Burden output: volts
Circuit impedance measurement in burden mode.
Transfer results to PC with USB
Transfer results to memory stick

32. Results stored in database.
PC Based Software
Results stored in database.
Sort on twelve fields.
Generate full report form including data and color graphs of all curves.
Files compatible with word processing and spread sheets.

33. Modes of Operation Auto mode: Manual mode: Burden mode:
Allows DCT to automatically complete a series of tests.
Manual mode:
Allows operator to manually raise and lower the voltage to make diagnosis.
Burden mode:
Current source for secondary injection

34. Comparison of models
Both models have identical features regarding tests, output, range, accuracy, keyboard, printer, memory capacity, memory stick, software and database.
Differences are listed below.

35. Test Automation
X2:
Check boxes on test screen are used to select the tests to be performed in automatic sequence.
X5:
A test plan conducts the required tests on up to ten ratios on a multi-ratio CT. Saves 140 plans.

36. Extent of Automation X2: X5
Completes all selected tests for one winding. X5
Completes all selected tests for up to ten ratios.

37. Conclusion
Contact your local representative or Adwel International for questions or further information.