High voltage high-breaking capacity VV fuse-links

Transcription

1 High fuse-links High fuse-links High high-breaking capacity VV fuse-links VV General information ET fuse-links named VV THERMO are designed to protect devices in switch-gears and other equipment (distribution transformers, capacitors, motors) from thermal and dynamic effects of shortcircuits and overs. Time- characteristics correspond to standard IEC , item Back-up fuse. They are suitable for installation in: indoor and outdoor switchgear gas (SF6)-insulated enclosures special service conditions (different from normal conditions, described in item 2.1. of standard IEC ) The most significant features of ETI high fuses: Low temperature rise bacause of low power dissipation High breaking capacity 50 ka Possibility of three different striker pin forces: 80 N and 120 N (with integ temperature dependent limiter) and 50 N. Reliable sealing system against humidity irruption Low switching s Upon a request, fuse links can be supplied into no-standard dimensions Overview of standard and no-standard dimmensions ET THERMO 2A 4A 6A 10A 16A 20A 25A 32A 40A 50A 63A 80A 100A 125A 160A 200A 250A 315A 7,2 kv 192 x Ø x Ø x Ø x Ø 68 x Ø x Ø x Ø 85 x Ø kv 192 x Ø x Ø 53 x Ø x Ø x Ø 68 x Ø x Ø 85 x Ø x Ø kv 292 x Ø x Ø 53 x Ø x Ø x Ø x Ø 68 x Ø x Ø 85 x Ø kv 292 x Ø 53 x Ø x Ø x Ø x Ø 85 x Ø x Ø 68 x Ø x Ø kv x Ø x Ø x Ø x Ø 85 standard dimmension no- standard dimmension 1 (021) (021)

2 High fuse-links Standards ETI VV (Medium Voltage) fuse-links comply with the following standards and specifications: IEC , Sixth edition 11/2005 Current limiting fuses DIN Hochspannungs-Sicherungen Nennspannung 3,6 bis 36kV VDE 0670 T402, Wechselstromschaltgeraete fuer Spannungen ueber 1kV, Auswahl von strombegrenzenden Sicherungseinsaetzen fuer Transformatorstromkreise / IEC Application guide for the selection of high limiting fuse-links for transformer circuits IEC Specification for high- fuse-links for motor circuit applications IEC High- fuses for external protection of power capacitors VV Certificates, Test reports CESI (Milan, Italy) certificate for 12kV, 17.5kV and 24kV KERI (Chang Wong, S.Korea) certificate for 7.2kV and 24kV ICMET (Craiova, Romania) test report for 36kV Test reports for 25kV, 38.5kV, 40.5kV and 42kV versions Construction ETI high fuses are designed to assure stable and reliable characteristics. The glazed porcelain tube (made in ETI own ceramic factory) is extremely high mechanical and thermal resistant. Galvanically protected contact caps made of electrolitic copper are nickel - or upon customer request silver plated. Caps are rolled by pressing into the groove of the tube. The tightness of this connection is assured by a special seal resistant to ageing and high temperatures. The design and method of production of the melting elements ensures precisely tolerances and stable time/ characteristics. Fuse elements are wounded on a ceramic carrier and electricaly welded on a special copper strips. The inside of the tube is filled with quarz sand with an exactly determined granulation and chemical structure. The sand guarantees good and reliable extinguishing of the electric arc. An important element in the fuse-link construction is also the striker system. Part of that system is temperature sensitive element, which reacts in cases of temperature increasing of the fuse-link due to various reasons. The reaction temperature is set to approximately 250 C on fuse tube surface. The system reacts in such a way that short time overloads do not cause the fuse to interroupt the circuit unnecessarily. Only when inadmissible values of surrounding temperatures are exceeded, the fuse open the switch via the striker pin. Because of these characteristics, ETI thermal striker pin is convenient for the protection of the fuse enclosure of SF6 switchgears which requires additional protection features against inadmissible temperatures of certain switchgear parts. Striker pin Type description, 7,2 kv example: VVC; 50N striker force (C mark). VVT-D; Temperature limiter (VVT), 80N striker force (D mark). ; Temperature limiter (VVT),120N striker force (E mark). 2 (021) (021)

3 High fuse-links VV Ordering Code Numbers (mm) VVC 50N VVT-D 80N THERMO 120N THERMO Tube diameter d (mm) weight U n [kv] [A] [kg] A A A A A A A A A A A A A / A A A A A A A A A A A A A A A A A A A A A A Note 1: Other ratings and dimensions can be supplied by customer request. For particular applications, please contact ETI technical team. Note 2: Blue colored types IEC dimensions. 3 (021) (021)

4 High fuse-links Ordering Code Numbers (mm) VVC 50N VVT-D 80N THERMO 120N THERMO Tube diameter d (mm) weight U n [kv] [A] [kg] A A A A A A A A A A A A A A A A A /12 80 A A A A A A A A A A A A A A A A A A A A A VV Note 1: Other ratings and dimensions can be supplied by customer request. For particular applications, please contact ETI technical team. Note 2: Blue colored types IEC dimensions. 4 (021) (021)

5 High fuse-links VV Ordering Code Numbers (mm) VVC 50N VVT-D 80N THERMO 120N THERMO Tube diameter d (mm) weight U n [kv] [A] [kg] A A A A A A A A A A A A A A A A /17,5 40 A A A A A A A A A A A A A A A A A A A Note 1: Other ratings and dimensions can be supplied by customer request. For particular applications, please contact ETI technical team. Note 2: Blue colored types IEC dimensions. 5 (021) (021)

6 High fuse-links Ordering Code Numbers (mm) VVC 50N VVT-D 80N THERMO 120N THERMO Tube diameter d (mm) weight U n [kv] [A] [kg] A A A A A A A A A A A A A A A /24 40 A A A A A A A A A A A A A A A A A A A Note 1: Other ratings and dimensions can be supplied by customer request. For particular applications, please contact ETI technical team. Note 2: Blue colored types IEC dimensions. VV 6 (021) (021)

7 High fuse-links VV Ordering Code Numbers (mm) VVC 50N VVT-D 80N THERMO 120N THERMO Tube diameter d (mm) weight U n [kv] [A] [kg] A A A A A A /36 10 A A A A A A A A ** ** derating factor to take into consideration. Special parameters required. Note 1: Other ratings and dimensions can be supplied by customer request. For particular applications, please contact ETI technical team. Note 2: Blue colored types IEC dimensions. 7 (021) (021)

8 High fuse-links Fuse bases for VV fuse-links 1-pole Indoor mounting type Rated code No. packaging [kv] [pcs] VVP 12 1p-N 7,2 and VVP 24 1p-N 17,5 and VVP 36 1p-N VV 1-pole Outdoor mounting type Rated code No. packaging [kv] [pcs] VVP 12 1p-Z 7,2 and VVP 24 1p-Z 17,5 and VVP 36 1p-Z Accessories Accessories for 3-pole Indoor fuse-bases type code No. packaging [pcs] VVP 12 3p-N VVP 24 3p-N VVP 36 3p-N Accessories for 3-pole Outdoor fuse-bases type code No. packaging [pcs] VVP 12 3p-Z VVP 24 3p-Z VVP 36 3p-Z Note: customer himself can assemble 3-pole fuse-base from 3pcs. of 1-pole fuse-base and 2pcs. of accessories. 8 (021) (021)

9 Technical data - VV High- high-breaking capacity VV fuse-links Technical data Rated breaking capacity Rated minimum breaking cold resistance power dissipation pre-arcing I 2 t value total I 2 t value [kv] (mm) I n [A] (ka) [mω] [W] [A 2 s] [A 2 s] , A , A A A A A A A A A A A A A A A / A A A A A A A A A A A A A A A A A A A VVC, VVT-D, VVC, VVT-D, VVC, VVT-D, 9 (021) (021)

10 Technical data - VV Technical data Rated breaking capacity Rated minimum breaking cold resistance power dissipation pre-arcing I 2 t value total I 2 t value [kv] (mm) I n [A] (ka) [mω] [W] [A 2 s] [A 2 s] , A , A A A VVC, VVT-D, 80 60, A A A A , A , A A A 60 60, A A VVC, VVT-D, A A A /12 80 A A A A , A , A A A A A VVC, VVT-D, A A A A A A A A A VVC, VVT-D, 200 A A (021) (021)

11 Technical data - VV Technical data Rated breaking capacity Rated minimum breaking cold resistance power dissipation pre-arcing I 2 t value total I 2 t value [kv] (mm) I n [A] (ka) [mω] [W] [A 2 s] [A 2 s] , A , A A A A VVC, VVT-D, A A A A A , A , A A A A A VVC, VVT-D, / A A A A A A A , A , A A A A A VVC, VVT-D, A A A A A A (021) (021)

12 Technical data - VV Technical data Rated breaking capacity Rated minimum breaking cold resistance power dissipation pre-arcing I 2 t value total I 2 t value [kv] (mm) I n [A] (ka) [mω] [W] [A 2 s] [A 2 s] , A , A A A VVC, VVT-D, 20 A 31, A A A A , A , A A A A A VVC, VVT-D, /24 40 A A A A A A , A , A A A A A VVC, VVT-D, A A A A A A A (021) (021)

13 Technical data - VV Technical data Rated breaking capacity Rated minimum breaking cold resistance power dissipation pre-arcing I 2 t value total I 2 t value [kv] (mm) I n [A] (ka) [mω] [W] [A 2 s] [A 2 s] , A ,3 164 VVC, VVT-D, 6 A A A , A , A /36 10 A A A VVC, VVT-D, ,5 25 A A A A A** Force / travel striker pin diagram Connection in indoor switchgear, example: striker force 120 N VVT-D striker force 80 N VVC striker force 50 N 13 (021) (021)

14 Fuse-link Technical data - VV Cut-off diagram for VV-Thermo fuse links Cut-off Prospective Prearcing time (s) Time- characteristics for VV-thermo fuse links A 4A 6A 16A 25A 40A 50A 80A 125A 10A 20A 32A 63A 100A 160A Prearcing time (s) Prospective Prospective 14 (021) (021)

15 Technical data - VV Selection of fuses for transformer protection For HV fuse-link selection, following transformer technical features has to be known: Rated power P n (kva) Short-circuit U cc (%) Rated I nt Inrush usually between 8-12xI nt Short-circuit I cc Overload usually 1.4 I nt Maximum short-circuit duration. Standard 2 sec for transformers up to 630 kva and 3 sec for higher powers Following HV fuse-link technical features has to be known: Rated U n (kv) Rated I n I/t Characteristics According to the curves Melting (0.1sec) I f (0.1sec) Melting at 2s ec or 3sec melting time Minimum breaking I 3 Breaking capacity I 1 (ka) General about transformer protection: Fuse-link U n must be higher then network. Maximum fuse-link breaking I 1 must be higher then short circuit- Icc. Inrush should not melt the fuse-link. Melting at 100 msec must be higher than 12 times transformer Fuse-link has to operate before the expected short-circuit damage the transformer Icc > I f (2 sec) or Icc > I f (3 sec) Fuse-link must be able to withstand possible short duration overloads. I n FUSE > 1.4 I n TRAFO Selection table for VV - THERMO back-up fuse links Pt (kva) Transformer primary Ip at 6 kv Inrush 6/7,2 kv 10/12 kv 15/17.5kV HV Fuse-link min max LV Fuse- Link NH gg I LV Transformer primary Ip at 10 kv Inrush HV Fuse-link LV Fuse- Link NH gg Transformer primary Ip at 15 kv Inrush HV Fuse-link * * 250* * 315* * 1600 * Note: nonstandard tube dimmension min max I LV min max LV Fuse- Link NH gg I LV 15 (021) (021)

16 Technical data - VV Selection table for VV - THERMO back-up fuse links Pt (kva) Transformer primary Ip at 20 kv Inrush 20/24 kv 30/36 kv HV Fuse-link min max LV Fuse- Link NH gg I LV Transformer primary Ip at 30 kv Inrush HV Fuse-link min max LV Fuse- Link NH gg I LV 1-pole fuse-base INDOOR MOUNTING OUTDOOR MOUNTING Rated [kv] A [mm] B [mm] C [mm] D [mm] E [mm] F [mm] 7,2 and ,5 and ,2 and ,5 and internal fuse base 16 (021) (021)

17 Technical data - VV external fuse base Definitions and terms Back-up fuse-links According to standard IEC Fifth edition ( ), item 3.3.3, Back-up fuse is -limiting fuse capable of breaking, under specified conditions of use and behaviour, all s from the maximum breaking (I 1 ) down to the minimum breaking (I 3 ). Back-up fuse links should not operate below theirs Ľminimum breaking ę. If the short-circuit of the transformer is lower than the minimum breaking, additional protection must be provided. Rated range s ETI VV Thermo fuse-links must be ope at the. At lower operating s without limitation provided, please contact ETI team. Breaking capacity I 1 This value (sometimes named maximum breaking of indicates, that this is the maximum which can be interrupted by the fuse-link. I 1 should be greather than the maximum expected short circuit at the fuse-link site. Minimum breaking I 3 This value (sometimes named minimum breaking is specified for Back-up fuse-links. Up from this, fuse-link is capable to breaking fault. Power dissipation of a fuse-link P n The power dissipation of a VV Thermo fuse-link is specified at the of the fuse-link. For calculations of protection with VV Thermo fuse-link, it should be noted, that operating is normally below half of the. Time- characteristics I/t characteristics represents the correlation between and time up to the melting of a silver fuse element. For coordination with other protection devices, melting integral must be referred for melting times below 100ms. Current limitation This is most significant advantage of fuse-links compared to mechanical switches. Contacts of that switches need much longer time as fuse-link to interrupt fault s. VV fuse-link interrupt fault within few miliseconds and sinusoidal does not reach its peak value. Switching s Between -limiting process, short circuit must be limited and reduced as soon as possible. This require a switching that exceed the normal system and force the to zero. Permissible value of switching is 2.2 times peak value of the maximum (021) (021)