Transformer Bushings Type COT

Transcription

1 Transformer Bushings Transformer Type COT Bushings... COT 050 Type COT kv to 5 kv up kvto to 5 kv A up IEC to 37 A IEC 37 E 3.8

2 Features If you need any transformer bushing proven in operation conditions around the world, Trench has it! experience in bushing manufacture for more than years available with porcelain or composite insulator on air side Transformer Bushings Type COT 050 and COT capacitive fine graded oilpaper insulation with long term experience computer optimized electrical field distribution proven high electrical withstand against transient or impulse stresses excellent long term stability due to extremely low partial discharge and power loss factor oil immersed part covered by epoxy resin tube providing high impact resistance electrode embedded in the epoxy resin tube avoids external shielding reduces distance to ground porcelain cemented into flange provides higher mechanical strength than level II of IEC 37 inclination in service up to from vertical; for COT and COT even horizontal operation possible horizontal transport for all types possible tan δ and PDvalues more than twice as good as requested by IEC 37 current rating can easily be increased up to 0A by exchanging the bolt with a removable split conductor on existing bushing To preserve our environment the free oil volume in COTbushings is minimized (see table page ) Certified ISO 900

3 Design Cut view general design Terminal Active part 3 Terminal (Al or Cu) for connection of overhead lines or bus bars and arcing horns. Our design provides a maintenance free termination and ensures that the connection will not become loose in service. 3 Assembly The whole bushing is tightened together by the central tube or conductor. Head Alcasted head with oil The active part is made of oilimpregnated wide band paper with layers of aluminium foil to control the electrical field radially and axially. Depending on the current rating, the paper and foil are wound on either a central tube or a solid conductor. 7 Flange Mounting flange with integrated test tap made of corrosion free aluminium alloy, machined to ensure an excellent seal between the bushing and the transformer. 5 expansion chamber and oil level indicator. The chamber is hermetically sealed against atmosphere. Oil filling COT bushings are filled with dryed, degassed insulating mineral oil. 8 CTPocket If current transformers are required on the bushing, the ground sleeve can be extended. 9 Oil side end The insulator on the oil side is made of an epoxy resin tube. It 5 Insulator is designed to stay installed during the intank drying Porcelain Insulator made of high grade electrotechnical porcelain according to IEC 85. The insulator is connected to the mounting flange using Portland cement and sealed with oring gasket. Instead of porcelain a composite insulator is also available. process of the transformer and can withstand temperatures up to C. 0 Endshielding For voltages starting with 5 kv a special aluminium electrode is cast into the end of the epoxy resin tube. This end shielding controls the electrical field 7 8 strength in this area to ground

4 One of our bushing assembly stations Test tap

5 Power frequency voltage withstand test including PDmeasurement Epoxy resin insulator with embedded electrode 5

6 Type COT No. Type Rated voltage U r Rated phase to earth voltage U r / 3 Test voltage sec. Impulse voltage,/50µs kv kv kv kv A Rated Connection to current transformer I r : cross section Cucond.: diameter mm mm L see fig.3 mm AD Arcing distance (min.) Standard Mass creepage approx. distance (min.) mm mm kg Cantilever test load (min.) N COT COT COT 50 COT 35 COT ,5 Comments related to columns...3: 0,0,05: Rated and test voltages acc. to IEC ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. Standard: 0, 0, : ) Class F insulated ) Removable solid rod copper conductor 09: Extension for current transformer. connection system see page...7 Other extensions on request

7 0 Rated current I r L L L L3 L L7 D D D 3 D3 D 5 D5 D 7 D7 min. 8 Øt 9 n 3 e see fig. A mm ,: Brown glazed porcelain, other colours and other creepage distances upon request 3: According to IEC 37 level II or better.,5: L and L depends on L. The values in the table are valid for L=0mm. If L>0mm add L to L and L.,3,7,: Other dimensions on request 7

8 Type COT No. Type Rated Rated phase voltage to earth U r voltage U r / 3 Test voltage sec. Impulse voltage,/50µs kv kv kv kv A Rated Connection to current transformer I r : cross section Cucond.: diameter mm mm L see fig.3 mm AD Arcing distance (min.) Standard Mass creepage approx. distance (min.) mm mm kg Cantilever test load (min.) N COT 550 COT 50 COT 750 COT Comments related to columns...3: 0,0,05: Rated and test voltages acc. to IEC ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond Standard: 0, 0, : ) Class F insulated ) Removable solid rod copper conductor 09: Extension for current transformer. connection system see page...7 Other extensions on request

9 0 Rated current I r L L L L3 L L7 D D D 3 D3 D 5 D5 D 7 D7 min. 8 Øt 9 n 3 e see fig. A mm ,: Brown glazed porcelain, other colours and other creepage distances upon request 3: According to IEC 37 level II or better.,5: L and L depends on L. The values in the table are valid for L=0mm. If L>0mm add L to L and L.,3,7,: Other dimensions on request 9

10 Dimensional Drawing view A, Flange view A D3 D D L D5 Pilot hole Ø 8x nxø t B oil level indicator test tap air outlet cut B, Flange drilling Øt D 3x5 e AD L3 L L Fig. Fig. Current transformer COT , A L7 e L D L grounded layer L L D D7 Details of lower ends see page...7 Fig. 3 Fig. Fig. 5 0

11 Standard Oil level indicator COT, COT Oil level indicator COT COT 050 Ø 0 Ø 0 Fig. Fig. 7 Test tap kv Air escape screw for turret COT COT 050 ORing gasket Flat gasket Multiple spring contact Fig. 8 Fig. 9

12 Options Magnetic oil level indicator Arcing horns Type COT COT COT 50 COT 35 COT 50 COT 550 COT 50 COT 750 COT 050 S min. max. mm S Ø Fig. 0 Fig. Voltage tap according to ANSI/IEEE Type A COT COT 050 Oil sampling device Multiple spring contact Valve Fig. Fig. 3

13 Recommendations for lead out Arrangement Embedded Electrode These bushings are equipped on the lower end with a cone shaped epoxy resin tube and an embedded electrode. Therefore additional barriers or electrodes may be omitted and distance to ground is reduced. External Shielding Bushings for higher currents may have an external shielding. Distance to ground has to be increased. R R S Oil conditions: Mineral oil with less than 0ppm watercontent and dielectric strength higher than kv (acc. to IEC 5). Fig. Fig. 5 8 Draw lead insulation COT COT 050 Ø Ø 50 5 Ø with draw lead with draw lead Fig. Fig. 7 Cable insulation and distance to grounded parts Type COT COT COT 50 COT 35 COT 50 COT 550 COT 50 COT 750 COT 050 min. insulation thickness S min. distance to grounded parts R R mm

14 Removable split conductor Free oil volumes COT... COT A bolt removable split conductor copper Type COT COT COT 50 COT 35 COT 50 COT 550 COT 50 COT 750 COT 050 volume l,,8,7,5,5 3,8,7 5,0 9,0 3 fixing screws Fig. 8 Ø 9 Oil side end COT, COT... 0A... 0A Ø Ø A Ø 9 8 conductor Ø Ø Ø Ø Ø removable copperconductor fixed copperconductor Fig. 9 Fig. 0 Fig.

15 Oil side end COT COT A... 0A... 00A Ø,7 Ø, Ø 9 conductor Ø Ø Ø Ø Ø removable copperconductor fixed copperconductor Fig. Fig. 3 Fig.... A... A Ø Ø 9 Ø Ø 0 fixed copperconductor fixed copperconductor Fig. 5 Fig. 5

16 Oil side end COT COT A... 0A... 00A Ø,7 Ø,7 shielding available on request Ø 9 conductor Ø Ø Ø 8 Ø 8 Ø 8 removable copperconductor fixed copperconductor Fig. 7 Fig. 8 Fig. 9 A A varnished aluminium 5,5 shielding available on request Ø 50 Ø Ø 0 Ø 8 Ø Ø fixed copperconductor fixed copperconductor with shielding Fig. Fig. 3

17 COT A... 0A... 00A Ø Ø shielding available on request Ø conductor Ø 38 Ø Ø Ø 9 Ø Ø 9 Ø Ø 9 removable copperconductor fixed copperconductor Fig. 3 Fig. 33 Fig A... A varnished aluminium 50 shielding available on request 5 Ø Ø Ø Ø 95 Ø 3 Ø fixed copperconductor fixed copperconductor with shielding Fig. Fig. 3 7

18 Product Range Quality Bushings for Power Transformers up to 75 kv, A (>5 kv see separate brochure E 3.90) High Current Application up to 3 kv, 0 A Transformer to SF connection up to 550 kv GasInsulated Switchgear (GIS) up to 0 kv, 00 A Generators up to 3 kv, 5000 A Railways Buildings up to kv, 00 A Bushings according to all main standards as: IEC ANSI (see separate brochure E 3.7) BS UTE Bushings according to customer s special specification At Trench quality is a way of life. Trench quality assurance complies with the most stringent standard of ISO 900. Certified by AFAQ since 99. Trench Austria GmbH Paschinger Strasse 9, Postfach 3 A LinzLeonding/Austria Phone Fax sales@trenchaustria.at Trench Brasil LTDA Via Expressa de Contagem, 85 CEP: Cpmtagem, MG Brasil Phone Fax trenchbrasil@ca.trenchgroup.com Trench Limited Coil Product Division 7 Maybrook Drive, Scarborough Ontario, Canada MV B Phone () Fax () sales@ca.trenchgroup.com Trench Limited Instrument Transformer Division 390 Midwest Road, Scarborough Ontario, Canada MP 3B5 Phone () 7570 Fax () sales@ca.trenchgroup.com Trench France S.A., rue du Général Cassagnou B.P. 70 F 8 StLouis Cedex/France Phone Fax sales@trenchfrance.com Trench Germany GmbH Nürnberger Strasse Bamberg/Germany Phone Fax sales@trench.de Trench Switzerland AG Lehenmattstrasse 3 CH 8 Basel/Switzerland Phone Fax sales@trench.ch