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StandardsATAMER DIŞ TİC. A.Ş.
0312 473 44 24
Content
Introduction
Standards
- IEC 60502-2014- CENELEC HD 620- IEEE 400 - 2012- IEEE 400.2 – 2013- IEC 60060-3
VLF Cable Testing
2
StandardsIEC 60502-2014
3Ref. IEC 60502-2014, p. 11-12
Significant technical change:Þ g) the inclusion of a 0,1 Hz test after installation!
4
StandardsIEC 60502-2014
Ref. IEC 60502-2014, p. 45
Content
Introduction
Standards
- IEC 60502-2014- CENELEC HD 620- IEEE 400 – 2012- IEEE 400.2 – 2013- IEC 60060-3
VLF Cable Testing
5
European Standard for Cable After Laying TestCENELEC HD 620 S1 and 621 S1 1)
HV Test for PE or XLPE Cables from 6 to 36 kV
Method Frequency Test voltage [RMS] Testing time
VLF 0,1 Hz 3 x Uo 1 hour
Power Freq. 50 Hz 2 x Uo 1 hour
1) Paper insulated or mass impregnated cables like PILC a DC test with above mentioned
parameters is recommended
StandardsCENELEC HD 620
Ref. CENELEC HD 620(S1)-1996, p. 5-C-19
Content
Introduction
Standards
- IEC 60502-2014- CENELEC HD 620- IEEE 400 – 2012- IEEE 400.2 – 2013- IEC 60060-3
VLF Cable Testing
7
8
IEEE 400 - 2012 IEEE 400.2 - 2013
New standards available
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1) HVDC testing not recommended on XLPE cables !!!
StandardsIEEE 400 - 2012: what’s new?
Ref. IEEE400-2012, p.14
StandardsIEEE 400 - 2012
HVDCVLF Sinus MWT with tan δ: Useful
10Ref. IEEE400 2012, p. 3 and p.43
Content
Introduction
Standards
- IEC 60502-2014- CENELEC HD 620- IEEE 400 – 2012- IEEE 400.2 – 2013- IEC 60060-3
VLF Cable Testing
11
IEEE 400.2 - 2004 Test level of 2 Uo to 3 Uo, or acc. to table for 5 kV – 35 kV cablesDifferentiation between
- RMS value for sinusoidal waveform- Peak value for rectangular/cosine rectangular waveform
Testing duration 15 to 60 min., recommended acc. to [Moh]-study 30 min.
Effect: - lower stress - lower tree growth rate
StandardsIEEE 400.2 - 2013
StandardsIEEE 400.2 - 2013
VLF MWT implemented as useful toolRef. IEEE400.2 2013, p. 9
Voltage level up to 69kV covered
StandardsIEEE 400.2 - 2013
Ref. IEEE400.2 2013, p. 11
MWT as a replacement of the simple withstand test –with reduced test time, if TD values remain stable
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StandardsIEEE 400.2 - 2013
Ref. IEEE400.2 2013, p. 10
Content
Introduction
Standards
- IEC 60502-2014- CENELEC HD 620- IEEE 400 – 2012- IEEE 400.2 – 2013- IEC 60060-3
VLF Cable Testing
16
1) Distortion – minimum distortion required by IEC standard
IEC 60060-3
Definition of VLF voltage - max. distortion of ± 5 % (Peak/RMS < √2±5%)
Reason: Reproducibility! Voltage shape should not affect the testing result!
Competitor B >> 5 %True Sinewave < 0.5 % Competitor A >> 5 %
StandardsIEC 60060-3
Sinewave competitorLoad Current > 5 % @ 300nF
Sinewave competitor Load Current >> 5 %@ 27nF
BAUR True Sinewave Voltage and Current < 0.5 % from 10nF – 10µF
1) Distortion – minimum distortion required by IEC standard
StandardsIEC 60060-3
2) Symmetry – avoiding space charges
+-
(+) and the (-) half wave have the same peak-value and shape: No remaining DC offset!IEC60060-3: (+) and (-) peaks must not differ by more than 2%
+-
(+) and the (-) halfwave:Different peak-value and shape!Remaining HVDC offset!
Space charging!
Remaining DC offset
StandardsIEC 60060-3
Charging voltage
Distance in insulation
0
Voltage distribution after grounding
Voltage distribution during DC test
~kVRemaining space charge voltage
DC test voltage
void
Space Charge in XLPE, effect of DC test
Especially of aged PE, XLPE cables:long term space charges can be created
Remaining voltage offset as problem, if the cable is put back into service
StandardsIEC 60060-3
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1) HVDC Testing is not recommended anymore
2) VLF Sinusoidal tan-delta Monitored Withstand Test recommended as useful
Why sinusoidal VLF? And why BAUR truesinus® VLF?
Why tan-delta and partial discharge?
What is a monitored withstand test? What are the benefits?
New standards: Summary
Thank you for your kind attention!
If you have any questions, please feel free to ask…
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