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Test Performance Record for LAPEM NXCT 345 kV

© 2005 NxtPhase T&D Corporation Page 21

8.7.4 Impulse-voltage withstand test

The impulse-voltage withstand tests shall be made by applying the voltage given in 6.1.1.3.

A standard lightning impulse in accordance with IEC 60060 shall be used. The parameters

are:

• front time: 1,2 µs ± 30 %

• time to half value: 50 µs ± 20 %

• output impedance: 500 ?± 10 %

• output energy: 0,5 J ± 10 %

The length of each test lead shall not exceed 2 m.

The impulse voltage shall be applied to the appropriate points accessible from the outside of

the device, the other circuits and the exposed conductive parts being connected to earth.

During the test, no input or auxiliary energizing quantity shall be applied to the device.

Three positive and three negative impulses shall be applied at intervals of not less than 5 s.

Acceptance criteria: no flashover is accepted and after the test, the ECT shall still comply

with basic accuracy tests.

Summary of Low Voltage Components Voltage Withstand Test:

All of NxtPhase Generation 3 electronics have been designed to meet the requirements of this section of the IEC Standard. At this time, no test results are available, as the testing is not completed. Test results will be provided as soon as reports are generated once testing is

complete.

Original Low Voltage Components Voltage Withstand Test Report:

See comment above.


© 2005 NxtPhase T&D Corporation 2

The IEC Standard Requirements

8.8 EMC tests

8.8.1 General

The tests shall be made to prove the compliance with 6.1.5.

In many cases an electronic transformer may be divided into a number of major

subassemblies such as, for example, circuits located in control cubicles and circuits located in

the switchgear area. EMC tests relevant for the applied technology of electronic transformer

have to be carried out on each major subassembly the full electronic transformer being in

operation or the missing subassemblies being simulated. An example of major subassembly

division is given in figure 15.

Figure 15 – Example of subassembly subjected to EMC tests

(1) HV line

(2) Enclosure port

(3) Ground port

(4) Signal port

(5) Command port

(6) Communication port

(7) a.c. power port

(8) d.c. power port

Sub-assembly 1 : "outdoor part" in switchgear area

Sub-assembly 2 : "indoor part" in control cubicle area

Switchyard area

Control cubicle area

(1)

(2)

(3)

(4), (5), (6),(7), (8)

(7), (8)

(4), (5), (6)

(3)

(2)

Sub-assembly 1Sub-assembly 2

Link between

Sub-assembly 1 and 2



8.8.2 General conditions during EMC tests

The general conditions for EMC tests are described in IEC 61000-4-1 and CISPR 11.uring the

EMC tests, the length of cable between the ECT and test equipment and between subassembly

1 and 2 should be the maximum specified by the manufacturer and the arrangement of the

cable shall, as far as practicable, represent in-service conditions.

8.8.3 EMC emission tests

An emission test will be performed according to the CISPR 11 testing procedure. The test

limits will be those of group 1 class A. The test shall preferably be performed on the complete

assembly but for ease of testing in case one of the possible subassemblies contains no

electrical parts, that test can be performed on the remaining subassemblies.

Summary of EMC Emission Tests:

Test Result: PassGeneration 3 Electronics Serial # Prototype

Rated Voltage: 69 kV Rated Current: 2000 A

Protocol Labs report #: 03056, Date: 4/26/2005Test date: 1/31/2005 through 2/25/2005

Basic Standards:Conducted Emissions (CISPR 11/22 Class A): Pass [X] Fail [ ] N/A [ ]Radiated Emissions (CISPR 11/22 Class A): Pass [X] Fail [ ] N/A [ ]

Conducted Emissions (FCC Part 15/B Class A): Pass [X] Fail [ ] N/A [ ]Radiated Emissions (FCC Part 15/B Class A): Pass [X] Fail [ ] N/A [ ]Conducted Emissions (ICES 003 Class A): Pass [X] Fail [ ] N/A [ ]Radiated Emissions (ICES 003 Class A): Pass [X] Fail [ ] N/A [ ]

Conducted Emissions (EN55011/22 Class A): Pass [X] Fail [ ] N/A [ ]Radiated Emissions (EN55011/22 Class A): Pass [X] Fail [ ] N/A [ ]

Electrostatic Discharge (61000-4-2) Level 4: Pass [X] Fail [ ] N/A [ ]Electrostatic Discharge (IEEE C37.90.3) Level 4: Pass [X] Fail [ ] N/A [ ]Electrostatic Discharge (IEC 60255-22-2) Level 4: Pass [X] Fail [ ] N/A [ ]

Testing was performed per the following standards, pursuant to IEC 60044-8:2002 and EN 50263:2000.

Radiated and Power Line Conducted Emission tests were performed using measurement procedure CISPR 11. Radiated emissions were performed on an open area 10m test site.

Table 5.2-1 Emissions Test Results - International

Test Standard Description Result

ConductedEmissions

CISPR 11/22Class A Limits EN55011/22

Class A Limits

The Conducted Emissions are measured on the phase and Neutral Power lines in the 0.15 - 30.0 MHz range.

Pass

RadiatedEmissions

CISPR 11/22Class A Limits EN55011/22

Class A Limits

The radiated emissions are measured in the 30-1000MHz range.

Pass



Test Standard Description Result

Power Line

Harmonics

EN 61000-3-2

Class D Limits

Maximum 1.08, 2.3, 0.43, 1.14, 0.3, 0.77,

0.23 A.... for 2nd to nth Harmonic

N/A

DCPowered

Power line Fluctuations

(Flicker)

EN 61000-3-3Pst <1, Plt < 0.65

Maximum 3% total Harmonic Distortion N/ADC

Powered

Original EMC Emission Test Report:

See Appendix A – NXCT Gen 3.0 Project, Current Transducer Systems for Metering and Protection, Applications EMC Compliance Test Report –D00559R00.00


8.8.4 EMC immunity tests

The test shall be performed on a port-by-port basis, guidance for the identification of ports

being given in figure 15.

8.8.4.1 Harmonic and interharmonic disturbance test

The test shall be performed according to the test procedure of IEC 61000-4-13. The severity

level is class 2 (full harmonic distortion 10 %). The assessment criterion is given in 6.1.5.3.

8.8.4.2 Slow voltage variation test

The test shall be performed according to the test procedure of IEC 61000-4-11 for a.c. power

supply and IEC 61000-4-29 for d.c. power supply. The voltage variations used are from +10

% to 20 % of the nominal voltage of the a.c. power supply and from +20 % to 20 % of the

nominal voltage of the d.c. power supply. The assessment criterion is given in 6.1.5.3.

8.8.4.3 Voltage dips and short interruption test

The test shall be performed according to the test procedure of IEC 61000-4-11 for a.c. power

supply and IEC 61000-4-29 for d.c. power supply.

• The voltage dip used for the test is 30 % of the nominal voltage of the a.c. power supply

during 0,02 s. The voltage interruption test is performed during 0,1 s for a.c. power

supply.

• The voltage dip used for the test is 40 % of the nominal voltage of the d.c. power supply

during 0,05 s.

• The voltage interruption test is performed during 0,05 s or 0,02 s for d.c. power supply.

• The assessment criterion is given in 6.1.5.3.



8.8.4.4 Surge immunity test

The test shall be performed according to the test procedure of IEC 61000-4-5. The test

generator to be used is the combination wave (hybrid) generator (IEC 61000-4-5, 6.1) with

standard 1,2/50 s voltage waveform (open-circuit) and 8/20 s current waveform (short-

circuit). The test level is according to installation class 4 (4 kV common mode, 2 kV

differential mode). The assessment criterion is given in 6.1.5.3.

8.8.4.5 Electronic fast transient/burst test

The test shall be performed according to the test procedure of IEC 61000-4-4, the test level

being class 4 (4 kV test voltage at 2,5 k Hz repetition rate on power supply port and 2 kV at 5

k Hz repetition rate on input/output signal, data and control ports – common mode). The test

will be carried out using the coupling/decoupling network on the power supply port and the

capacitive coupling clamp on I/O and communication ports. The assessment criterion is given

in 6.1.5.3.

8.8.4.6 Oscillatory waves immunity test

The test shall be performed according to the test procedure of IEC 61000-4-12. The test

generator to be used is the damped oscillatory wave generator (IEC 61000-4-12, 6.1.2). The

test voltage will be 2,5 kV common mode and 1 kV differential mode both for power supply

and control/signal lines (as in IEC 60255-22-1). Test frequency will be 1 M Hz at 400/s

repetition rate (as in IEC 60255-22-1). The assessment criterion is given in 6.1.5.3.

8.8.4.7 Electrostatic discharge test

The test shall be performed according to the test procedure of IEC 61000-4-2. The test level is

class 2 (4 kV test voltage), which gives protection in antistatic environments (like concrete)

for relative humidity as low as 10 % (see also IEC 61000-4-2, clause A.4). The assessment

criterion is given in 6.1.5.3.

8.8.4.8 Power-frequency magnetic field immunity test

The test shall be performed according to the test procedure of IEC 61000-4-8. Test level is 5

(100 A/m steady state and 61 000 A/m ? ?1). The assessment criterion is given in 6.1.5.3.

8.8.4.9 Pulse magnetic field immunity test

The test shall be performed according to the test procedure of IEC 61000-4-9. Test level is 5

(61 000 A/m peak). The assessment criterion is given in 6.1.5.3.

8.8.4.10 Damped oscillatory magnetic field immunity test

The test shall be performed according to the test procedure of IEC 61000-4-10. Test level is

class 5 (100 A/m test field). The assessment criterion is given in 6.1.5.3.

8.8.4.11 Radiated, radiofrequency, electromagnetic field immunity test

The test shall be performed according to the test procedure of IEC 61000-4-3. Test level is

class 3 (10 V/m field strength). The assessment criterion is given in 6.1.5.3.



Summary of EMC Immunity Tests:

Test Result: Pass

Generation 3 Electronics Serial # PrototypeRated Voltage: 69 kV Rated Current: 2000 A

Protocol Labs report #: 03056, Date: 4/26/2005

Test date: 1/31/2005 through 2/25/2005

Radiated RF Susceptibility (61000-4-3) Level 3: Pass [X] Fail [ ] N/A [ ]

Radiated RF Susceptibility (IEC 60255-22-3) Level 3: Pass [X] Fail [ ] N/A [ ]Radiated RF Susceptibility (IEEE C37.90.2) 35V/m: Pass [X] Fail [ ] N/A [ ]Radiated RF Susceptibility (IEEE C37.92) 35V/m: Pass [X] Fail [ ] N/A [ ]

Electrical Fast Transient/Burst (61000-4-4) Level 4: Pass [X] Fail [ ] N/A [ ]Electrical Fast Transient/Burst (IEEE C37.90.1) Level 4: Pass [X] Fail [ ] N/A [ ]Electrical Fast Transient/Burst (IEC 60255-22-4) Level 4: Pass [X] Fail [ ] N/A [ ]

Surge Immunity (61000-4-5) Level 4: Pass [X] Fail [ ] N/A [ ]Surge Immunity (IEC 60255-22-5) Level 4: Pass [X] Fail [ ] N/A [ ]Conducted RF Immunity (61000-4-6) Level 3: Pass [X] Fail [ ] N/A [ ]

Conducted RF Immunity (IEC 60255-22-6) Level 3: Pass [X] Fail [ ] N/A [ ]Power Frequency Magnetic Field Immunity (61000-4-8)Level 5: Pass [X] Fail [ ] N/A [ ]

Pulse Magnetic Field Immunity (61000-4-9) Level 5: Pass [X] Fail [ ] N/A [ ]Damped Oscillatory Magnetic Field (61000-4-10) Level 5: Pass [X] Fail [ ] N/A [ ]Oscillatory Waveforms Immunity (61000-4-12) Level 3: Pass [X] Fail [ ] N/A [ ]

Oscillatory Waveform Immunity (IEC 60255-22-1) Level 3: Pass [X] Fail [ ] N/A [ ]Surge Withstand Capability, Oscillatory Waveform (IEEE C37.90.1) Pass [X] Fail [ ] N/A [ ]Voltage Dips Interruptions & Variations (61000-4-29),

200ms Interrupt Pass [X] Fail [ ] N/A [ ]Voltage Dips Interruptions & Variations (61000-4-29),1200ms Interrupt Pass [X] Fail [ ] N/A [ ]

Voltage Interruptions (IEC 60255-11) 200ms Interrupt Pass [X] Fail [ ] N/A [ ]

Tests were conducted on a sample of the equipment for the purpose of demonstrating

compliance with the following standards.

Testing was performed per the following standards, and the EUT responded as noted.



Table 7.1-1 Immunity Test Summary

Criterion(See Pass/Fail

Criteria Section)

ApplicableStandard

DescriptionTest or

MeasurementRequired

Level

Metering Protection

Result

ESDEN 61000-4-2

IEC 60255-22-2

IEEE C37.90.3

Air Discharge up to 15 kV and Contact Discharge at 8 kV at

several locations with 10 positive and 10 negative discharges per

location.

Air Discharge

Contact Discharge

+/- 15 kV

+/- 8 kV B A Complies

Radiated

ImmunityEN 61000-4-3IEC 60255-22-

3

Subject to electromagnetic field

of 10V/m from 80 MHz to 1000 MHz and 1.4 GHz to 2.0 GHz.

Modulated

FrequencyField

1 kHz 80% AM

10 V/mA A Complies

RadiatedImmunity

IEEE C37.90.2

IEEE C37.92

Subject to electromagnetic field of 35 V/m from 25 MHz to 1000

MHz

Keyed Keyed35 V/m

A A Complies

EFT/BurstEN 61000-4-4IEC 60255-22-

4IEEE C37.90.1

EFT/Burst of 4.0 kV is coupled to the all I/O and control signals,

respectively and 4.0 kV is

injected on the Power Line.

Direct injection

Coupling Clamp

+/- 4.0 kV

+/- 4.0 kV B A Complies

SurgeImmunity

EN 61000-4-5IEC 60255-22-

5

4 kV Positive and Negative Surges are injected in Common

Mode, Differential Mode, as well as shielded lines

Line to GroundLine to Line

Applied to the Shield

+/- 4.0 kV+/- 2.0 kV

+/- 4.0 kV B A Complies

Conducted RFEN 61000-4-6IEC 60255-22-

6

All lines are RF coupled to 10Vrms level from 0.150 – 80

MHz.

ModulatedFrequency

Field

1 kHz 80% AM10 Vrms

B A Complies

PowerFrequency

Magnetic FieldEN 61000-4-8

For magnetically susceptible apparatus only. Subject to a

magnetic Field of 100A (RMS) A/m for 60 seconds and 1000

(RMS) A/m for 3 seconds.

Applied on all 3 axis

100 A/m for 60 sec

1000 A/m for 3 sec

A A Complies

MagneticPulse

EN 61000-4-9

For magnetically susceptible apparatus only. Subject to

magnetic s pulse Field of 1000

A/m is applied


1000 A/mB A Complies

DampedOscillatory

Magnetic Field

EN 61000-4-10

Magnetic field-tests for electronic equipment in H.V. sub-stations.Applied on the X, Y and Z-axis.


100 A/mB A Complies

OscillatoryImmunity

EN 61000-4-12IEC 60255-22-

1IEEE C37.90.1

Repetitive, damped oscillatory waves occurring mainly in power,

control and cables installed in H.V. and M.H. sub –stations.

Common Mode:

Differential Mode

2.5 kV

2.5 kVB A Complies

Slow Voltage Variations

EN 61000-4-29

The DC voltage is varied Voltage Varied +/- 20%A A Complies

VoltageInterruptions

EN 61000-4-29IEC 60255-11

The voltage on the power supply is interrupted for a set amount of

timeVoltage interrupted 100% for up to

200ms

A

50ms

A

200ms

Complies

Voltage DipsEN 61000-4-29

The voltage and current are varied for a set amount of time

Voltage Dips

Current Dips

50% for 100ms

60% for 50msA A Complies



Original EMC Emission Test Report:

See Appendix A – NXCT Gen 3.0 Project, Current Transducer Systems for Metering and Protection, Applications EMC Compliance Test Report –D00559R00.00


8.9 Accuracy test

8.9.1 General

The following accuracy tests are applied to measuring electronic current transformer and to

protective electronic current transformer. Test circuits are given in annex B for digital output

and annex C for analogue output.

Basic accuracy tests

8.9.1.1 Basic accuracy tests for measuring electronic current transformer

To prove compliance with 12.2, tests shall be made at each value of current given in tables 19,

20 and 21 at rated frequency, at rated burden (if relevant), and at ambient temperature, unless

otherwise specified. Current transformers having rated primary current factor greater than 1,2

shall be tested at rated primary extended current instead of 1,2 times the rated primary current.

NOTE The test can be carried out using a pure delay time device inserted between the reference transformer and the

accuracy measurement system.

8.9.1.2 Basic accuracy test for protective electronic current transformer

To prove compliance with 13.1.3, the test shall be made at rated primary current (see table

22), at rated frequency, at rated burden (if relevant) and at ambient temperature.

NOTE The test can be carried out using a pure delay time device inserted between the reference transformer and the accuracy measurement system.

8.9.2 Temperature cycle accuracy test

In addition to the basic accuracy tests made in accordance with 8.9.2, the temperature cycle

accuracy test shall be performed in the following conditions:

?

• at rated frequency;

• ?at rated current or rated primary extended current applied continuously;

• ?at rated burden (if relevant);

• ?with indoor and outdoor components exposed to their specific maximum and minimum

ambient air temperature. A cycle test in accordance with figure 16 shall be performed.



Figure 16 – Temperature cycle accuracy test

Minimum temperature variation rate is 5 K/h. It can be higher only if allowed by the

manufacturer.

The thermal time constant shall be declared by the manufacturer.

NOTE Time needed to stabilize the temperature of the electronic current transformer depends mainly on the size and

construction of the transformer.

For electronic current transformers, partially indoor, partially outdoor, the tests shall be made

for indoor and outdoor parts, each one at both extremes of relevant temperature range,

respecting the following rules:

• ambient air temperature for both parts;

• maximum temperature for indoor part when maximum temperature for outdoor part;

• minimum temperature for indoor part when minimum temperature for outdoor part.

In normal service conditions the measured error of every measuring point should be within

the limits of the relevant accuracy class.

8.9.3 Test for accuracy versus frequency

In addition to the basic accuracy tests made in accordance with 8.9.2, tests for accuracy shall

be made at the two extremes of standard reference range of frequency given in 5.1.5, at rated

current, at rated burden (if relevant) and at constant ambient temperature.

The error shall be within the limits of the relevant accuracy class.

NOTE Measurement with different frequencies are performed with a test circuit . For the tests, accuracy measurement system calibrated at rated frequency may be acceptable.

8.9.4 Test for accuracy in relation to replacement of components

To prove compliance with clause 0 the following test shall be performed. The ability of the

electronic current transformer to fulfill its accuracy class when some of its components are

replaced shall be proven by means of an accuracy test at room temperature, rated frequency,

rated current and rated burden (if relevant).



8.9.5 Test for signal-to-noise ratio

To prove compliance with 6.1.9 a test for signal-to-noise ratio shall be performed. The test

procedure shall be agreed upon between manufacturer and user. See D.2.3 for guidance.

8.10 Additional accuracy tests for protective electronic current transformers

8.10.1 Test for composite error

Tests shall be made at rated primary current to prove compliance with 13.1.3 in respect of

current error and phase error.

Compliance with the limits of composite error given in table 21 shall be demonstrated by a

direct test in which a substantially sinusoidal current equal to the rated accuracy limit primary

current is passed through the primary terminals with rated burden (if relevant).

The test may be carried out on an ECT similar to the one being supplied, except that reduced

insulation may be used provided that the same geometrical arrangement is retained.

NOTE Where very high primary currents and a single-bar primary conductor of ECT are concerned, the distance

between the return primary conductor and the ECT should be taken into account from the point of view of reproducing service conditions.

8.10.2 Test for transient performance

Compliance with the limits of instantaneous error up to t′?and/or t” and at accuracy limit

condition given in table 21 shall be demonstrated by a direct test in which a transient current

defined in 3.3.11 is passed through the primary terminals with rated burden (if relevant), rated

primary short-circuit current, rated primary time constant and rated duty cycle.

NOTE Where very high primary currents and a single-bar primary conductor of ECT are concerned, the distance between the return primary conductor and the ECT should be taken into account from the point of view of reproducing service conditions.



Summary of Accuracy Tests:

Test Result: Pass, meets 0.2S class

CT serial #: D0XXXXR00.00-001Rated Voltage: 345 kV Rated Current: 2000 A

Powertech report #: 14132-03-REP2, Date: 4/25/2003

Test date: 1/23/2003 through 1/27/2003

NXCT accuracy tests, in accordance with IEC 60044-8 (2002), were performed throughout a

battery of type tests required by the IEC standard. The NXCT was a metering class CT with 4V and 1A outputs at rated current.



Test Result: Pass, meets 0.2S classCT serial #: D0XXXXR00.00-001

Rated Voltage: 345 kV Rated Current: 2000 APowertech report #: 14132-03-REP3, Date: 4/25/2003

Test date: 1/23/2003

A linearity test was performed on the NXCT in accordance with IEC 60044-8 (2002). The resultsare presented in the table below.

Linearity Test Results:



Test Result: Pass, meets 0.2S classCT serial #: D0XXXXR00.00-001



A temperature cycle test was performed on the NXCT in accordance with IEC 60044-8 (2002). The results are presented in the charts below.

The test current was 1200A.



Test Result: PassCT serial #: D0XXXXR00.00-001



A temperature rise test at 3000 A was performed on the NXCT in accordance with IEC 60044-8(2002) and IEEE C57.13. The results are presented in the table below.



Test Result: Pass, class ACT serial #: D00246R00-420-001.

Rated Voltage: 420 kV Rated Current: 2000 ANxtPhase Document #: D00341R00.00, Date8/29/2003


A temperature rise test at 4000 A was performed on the NXCT in accordance with IEC 60044-8(2002) and IEEE C57.13. The NXCT was a protection class CT with a 0.2 V output at rated

current.

The NXCT passed the temperature rise test at 4000 Arms thermal current with a A class of insulation (60°C temperature rise of the bus) for classes not immersed in oil or bituminous

compound according to the IEC 60044-8 industry standard.

Original Accuracy Test Reports:

C:\Documents and Settings\arose\My Documents\power tech\GEN 2\Temperature rise test D00341.doc PROPRIETARY INFORMATION. Do Not Disseminate Without The Consent Of NxtPhase © Copyright 2003 Last Saved: 9/11/2003 2:34 PM Page 1 of 4

T1-Other Document

TEMPERATURE-RISE TEST (4000 A)

Doc #: D00341R00.00 Released Status: Preliminary

Author: Allen Rose Approver(s): Eric Hadley, Jim Blake

1. Revision History

RevisionLevel:

Revision Date: (YYYY-MM-DD)

SectionsAffected:

Description of Change: Revised by:

R00.00 2003-08-29 all First Document Release AHR

2. Introduction

This document reports the results of a temperature-rise test performed on a 2 turn protection NXCT on September 21, 2003. The test witnesses are Allen Rose, Eric Hadley, and Jim Blake. The NXCT has a serial number of D00246R00-420-001.

3. Scope

The test was performed in accordance with sections 5.1.6, 6.1.2, and 8.2 of the IEC 60044-8 industry standard with a 4000 Arms thermal current. The NXCT was fitted with a standard 4.5” round bus and 4 hole NEMA pad connectors. (See photos below.)

4. Results

The NXCT #D00246R00-420-001 passed the temperature rise test at 4000 Arms thermal

current with a A class of insulation (60 °C temperature rise of the bus) for classes not immersed in oil or bituminous compound according to the IEC 60044-8 industry standard.

Scale factor error, measured at the rated current of 2000 A, before test was 0.02% ±0.12% and after test and cool down, 0.13% ± 0.12%. The actual rise of the bus was 47 °Cabove ambient temperature. The phase offset is about -0.7° and remained constant throughout the test. The performance of the sensor before and after the 4000 A heat rise test did not change within the uncertainty of the measurements.

5. Related Standard Document Number Title

IEC 60044-8 Instrument transformers – Part 8: electrical current transducers

6. Definitions Term Definition

NXCT NxtPhase Current Transducer

DVM Digital volt meter

7. Test Metrology

The NXCT was tested for scale factor accuracy using a Knopp CT-5000 (with a 0.1Ωburden), Arbiter, and Agilent DVM 3458A. A SRS 530 lockin amplifier was used to monitor the scale factor during the test. AD590 temperature probes provided the temperature readings.

The accuracy of the AD590s are ±1° C. The accuracy of the combined Knopp and arbiter is 510 ppm for the current reading. The accuracy of the Agilent 3458A in this test arrangement is about 0.10 %. All instruments are NIST traceable. Total uncertainty on the current ratio or scale factor error is about 0.12 %.


8. Test diagram

*The lockin difference amplifier should not be connected to the NXCT output when reading the DVM output. The common mode noise on the NXCT output biases the DVM reading by about 20 mV, because the lockin difference amplifier grounds one side of the NXCT differential output.

The DVM should have a filter function of 20 to 100 Hz on.

9. Test Photographs

TransformerIsolatedCurrentSource4000 A

Knopp5000:1

Arbiter0.1 Ω

NXCT2000 A :0.2 V

LockinAmplifierwithdifferenceamp

DVM


10. Temperature profile of test

The slope of the bus bar temperature from 13.5 to 14.5 hours is 0.45 °C/h within the IEC

standard of 1 °C/h. The test was performed in still air. The head shows no steady state temperature rise above the air temperature with the 4000 A heating current.

8 10 12 14 16 18 20 22

Time (h)

20

30

40

50

60

70

80

Tem

per

ature

(oC

)

Temperature rise test data

Bus Bar

Clamp Base

Air

Head

Slope 0.45 oC/h


11. NXCT performance during the heat rise test

The scale factor error performance during the test shows that the head temperature rose with the heated air around the current source. The scale factor change shown below

represents 10 °C differential between the base, and the head. Our sensor is known to

exhibit a scale factor sensitivity to this difference of about 200 ppm/°C.

10 15 20 25 30

Time (h)

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

Scale

Facto

r E

rro

r (%

)

14

28

42

56

70

84

Tem

pera

ture

(oC

)

Scale factor error

Calibration points

Bus Bar

Head




8.11 Verification of the protection

8.11.1 Verification of the IP coding

In accordance with the requirements specified in 6.1.13.1 and 6.1.13.2, tests shall be

performed in accordance with IEC 60529 on the enclosures of all parts of the ECT fully

assembled as under service conditions.

8.11.2 Mechanical impact test

In accordance with the requirements specified in 6.1.13.3, enclosures for indoor installation

shall be subjected to an impact test. Three blows are applied to points of the enclosure that are

likely to be the weakest points. Devices such as connectors, displays, etc. are excepted.

The use of a spring-operated impact test apparatus as defined in IEC 60068-2-75 is

recommended.

After the test, the enclosure shall show no breaks and the deformation of the enclosure shall

not affect the normal function of the electronic current transformer, and shall not reduce the

specified degree of protection. Superficial damage, such as removal of paint, breaking of

cooling ribs or similar parts, or depression of small dimension can be ignored.

Summary of Verification of the Protection Tests:

All of NxtPhase Generation 3 electronics have been designed to meet all of the requirements of this section of the IEC Standard. At this time, no test results are available, as the testing is not completed. Test results will be provided once testing is complete and as soon as reports are generated

Original Verification of the Protection Test Report:

See comment above.


8.12 Tightness tests

The purpose of tightness tests is to demonstrate that the absolute leakage rate F does not

exceed the specified value of the permissible leakage rate Frel (6.1.11).

For gas-filled electronic current transformer, in general, only cumulative leakage

measurements allow calculation of leakage rates. For the application of an adequate test

method, reference is made to IEC 60694, 6.8 and to IEC 60068-2-17.

For oil-filed electronic current transformer, the tightness test shall be a type test on the

electromagnetic unit assembled as for normal service, filled with the liquid specified. A

minimum pressure of (0,5 ±0,1) X105Pa above the maximum operating pressure shall be

maintained during 8 h inside the e.m.u. The e.m.u. shall be considered to have successfully

passed the test if there is no evidence of leakage.



Summary of Tightness Tests:

These tests are not applicable to the NXCT equipment, as they use no oil or gas for insulation. The NXCT is built with a solid dielectric composite column insulator.


8.13 Vibration tests

8.13.1 Vibrations test for secondary parts

The secondary converter, the merging unit and secondary power supply are generally

comparable to electrical secondary equipment in the substation and shall be tested in

accordance with IEC 60068-2-6 with the secondary parts operating in the normal service

condition.

8.13.2 Vibration test for primary parts

The test arrangement shall, as far as reasonably practicable, represent the worst-case service

condition in respect of vibration. Vibration levels will vary depending on connection

arrangements, insulation type, and for circuit breakers, the actuation principle (spring

mechanisms are considered to generate higher vibration levels).

8.13.3 Vibration test for primary parts during short-time current

This test is performed to determine that the ECT operates correctly in the presence of

vibration resulting from busbar vibration caused by short-time current electromagnetic forces.

This test can be carried out in conjunction with short-time current test or composite error test.

5 ms after the last opening of the circuit-breaker, the r.m.s. value of the secondary output

signal of the ECT at rated frequency calculated over one period, which should theoretically be

“0”, shall not exceed 3 % of the rated secondary output. To represent the worst-case condition

with respect to vibration, the ECT should be connected via a rigid connection to the circuit-

breaker.

8.13.4 Vibration tests for primary parts mechanically coupled to a circuit- breaker

8.13.4.1 General

These tests shall also apply to GIS switchgear, medium voltage switchgear and dead tank

circuit -breaker mounted ECTs.

8.13.4.2 During operation

This test is performed to determine that the ECT operates correctly in the presence of

vibration resulting from circuit-breaker operation.

The circuit -breaker shall be operated through one duty cycle (open-close-open) without

current. 5 ms after the last opening of the circuit -breaker, the output signal of the ECT which

should theoretically be “0”, shall not exceed 10 % of peak value of the rated secondary

output. To represent the worst-case condition in respect of vibration, the circuit-breaker

should be connected via a flexible conductor.



8.13.4.3 Vibration endurance test

The circuit -breaker shall be operated without primary current 3 000 times as described in IEC

60056. ECT accuracy at rated current shall be measured before and after the test. The ECT

error following the test must not differ from that recorded before the test by more than half the

limit of error appropriate to its accuracy class.

NOTE Vibration levels generated by circuit -breakers have been found to be principally dependant on the actuation

principle. A circuit-breaker having a spring mechanism will generally produce higher levels of vibration, thus an ECT test on such a circuit-breaker may be considered valid for other circuit-breakers, subject to agreement between manufacturer and purchaser.

Summary of Vibration Tests:

Test Result: PassCT serial #: D0XXXXR00.00-001

Rated Voltage: 345 kV Rated Current: 2000 APowertech report #: 14114-27-00, Date: 8/27/2003


The NXCT was subjected to horizontal and vertical acceleration. A summary of the Powertech test report is given below.

Vibration conditions were as follows:

• Sine sweep 5 to 500 Hz in horizontal and vertical directions

• Sweep cycle is 1 octave/min.

• Amplitude 0.707 gs peak

• Test duration – one sweep (6 minutes 38 seconds)

Sensor output measurements were taken at 5, 10, 30, 50, 60, 70, 120 and the dominant frequency for the orientation being tested. The maximum vertical resonance was at 436.8 Hz and the maximum horizontal resonance was at 137.14 Hz.

Original Vibration Test Report: