Transformer Bushings Type COT 5... COT 050 4 kv to 45 kv up to A IEC 37
Features If you need any transformer bushing proven in operation conditions around the world, Trench has it! experience in bushing manufacture for more than 80 years available with porcelain or composite insulator on air side Transformer Bushings Type COT 050 and COT 5 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 40 from vertical; for COT 5 and COT 70 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 50A by exchanging the cable bolt with a removable split conductor on existing bushing To preserve our environment the free oil volume in COTbushings is minimized (see table page 4) Certified ISO 900
Design Cut view general design Terminal 6 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. 4 5 6 expansion chamber and oil level indicator. The chamber is hermetically sealed against atmosphere. Oil filling 4 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. Oil side end 9 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. Endshielding 0 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. 9 0 3
Product Range Bushings for Power Transformers up to 765 kv, A (>45 kv see e separatea brochure E 3.90) High Current Application up to 36 kv, 5000 A Transformer to SF6 connection up to 5505 kv One of our bushing assembly stations GasInsulated Switchgear (GIS) up to 800 kv, 6000 A Generators up to 36 kv, 45000 A Railways Buildings up to 44 kv, 00 A Bushings according to all main standards as: IEC ANSI (see separate ate brochure E 3.7) BS UTE Bushings according to customer s special specificationio Test tap 4
Quality At Trench qual lity is a way of life. Trench qu uality assurance complies with the most stringent stand dard of ISO 900. 0. Cert tified by AFAQ since 994. Power frequency voltage withstand test including PDmeasurement Epoxy resin insulator with embedded electrode 5
Type COT 5... 450 No. Type 0 0 03 04 05 06 07 08 09 0 3 Rated voltage U r Rated phase to earth voltage U r / 3 Test voltage 60sec. Impulse voltage,/50s kv kv kv kv A Rated Connection to current transformer I r cable: cross section Cucond.: diameter mm mm L4 see fig.3 mm AD Arcing distance (min.) Standard Mass creepage approx. distance (min.) mm mm kg Cantilever test load (min.) N 0 0 03 04 05 06 07 08 09 0 3 4 5 6 7 8 9 0 3 4 5 6 7 8 9 COT 5 COT 70 COT 50 COT 35 COT 450 4 36 5 7,5 00 Comments related to columns...3: 0,04,05: Rated and test voltages acc. to IEC 37 4 4 58 50 70 95 40 85 5 70 50 35 450 800 000 50 600 500 800 000 50 600 500 800 000 50 600 500 800 000 50 600 500 800 000 50 600 500 cable cable ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. cable cable ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. cable cable ) rem.cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. cable cable ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. cable cable ) rem. Cucond. ) fixed Cucond. fixed Cucond. fixed Cucond. 35 35 35 35 35 Standard: 0, 0, 500 35 340 475 600 8 600 900 0 80 540 8 9 3 36 37 43 48 5 6 6 35 36 54 75 3 3 40 44 6 88 40 40 5 56 80 06 07: ) Class F insulated ) Removable solid rod copper conductor 09: Extension for current transformer. connection system see page 4...7 Other extensions on request. 0 0 0 6
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 60kV (acc. to IEC 56). Fig. 4 Fig. 5 8 Draw lead insulation COT 550...750 COT 050 Ø 35 50 5 with draw lead with draw lead Fig. 6 Fig. 7 Cable insulation and distance to grounded parts Type COT 5 COT 70 COT 50 COT 35 COT 450 COT 550 COT 650 COT 750 COT 050 min. insulation thickness S 5 5 0 0 5 5 0 min. distance to grounded parts R R mm 65 75 85 0 35 45 50 80 75 5 0 0 375 7
Removable split conductor Free oil volumes COT 5... COT 050... 50 A cable bolt removable split conductor copper Type COT 5 COT 70 COT 50 COT 35 COT 450 COT 550 COT 650 COT 750 COT 050 volume l,6,8,7,5,5 3,8 4,7 5,0 9,0 3 fixing screws Fig. 8 Ø 9 Oil side end COT 5, COT 70... 000A... 50A 600... A Ø 9 8 5 conductor Ø 35 cable removable copperconductor fixed copperconductor Fig. 9 Fig. 0 Fig. 8
Oil side end COT 50... COT 450... 000A... 50A... 600A Ø 35,7 Ø 35,7 8 90 Ø 9 conductor Ø 35 Ø 35 cable removable copperconductor fixed copperconductor Fig. Fig. 3 Fig. 4... 500A... A 5 5 Ø 94 Ø 04 fixed copperconductor fixed copperconductor Fig. 5 Fig. 6 9
Oil side end COT 550... COT 750... 000A... 50A... 600A Ø 35,7 Ø 35,7 shielding available on request 8 8 4 8 5 5 90 5 Ø 9 conductor Ø 35 Ø 35 Ø 68 Ø 68 Ø 68 cable removable copperconductor fixed copperconductor Fig. 7 Fig. 8 Fig. 9 500A A varnished aluminium 5,5 shielding available on request 5 5 50 95 Ø 60 Ø 86 Ø 4 fixed copperconductor fixed copperconductor with shielding Fig. Fig. 3 0
COT 050... 000A... 50A... 600A shielding available on request 78 50 50 50 4 4 4 5 Ø 9 5 90 5 conductor Ø 38 Ø 35 Ø 9 Ø 9 Ø 9 cable removable copperconductor fixed copperconductor Fig. 3 Fig. 33 Fig. 34... 500A... A varnished aluminium 4 50 shielding available on request 5 5 5 70 Ø 80 Ø 95 Ø 34 Ø 60 fixed copperconductor fixed copperconductor with shielding Fig. 35 Fig. 36
Trench Facilities The Trench Group is your partner of choice for electrical power transmission and distribution solutions today; and for the development of your new technology solutions of tomorrow. Trench Austria GmbH Paschinger Strasse 49 Postfach 3 A4060 LinzLeonding Austria Phone: 4373679 Fax: 43736734 Trench Brasil Ltda Via Expressa de Contagem, 685 Contagem, Minas Gerais CEP 3370485 Brazil Phone: 5533395959 Fax: 55333988 Trench China MWB (Shanghai) Co., Ltd. No. 3658, Jiancheng Road Minhang, Shanghai Peoples Republic of China 0045 Phone: 865470088 Fax: 8654738 Trench High Voltage Products Ltd., Shenyang No. Zhengliang Er. Road Jing Shen Xi San Street Dao Yi Economic Development Zone Shenyang 036 P.R. China Phone: 864897688 Fax: 8648973700 Trench Limited Bushing Division 43 Monarch Avenue Ajax, Ontario Canada LS G7 Phone: 90546665 Fax: 9054667 Trench Limited Coil Product Division 7 Maybrook Drive Scarborough, Ontario Canada MV 4B6 Phone: 4698808 Fax: 469809 Trench Limited Instrument Transformer Division 390 Midwest Road Scarborough, Ontario Canada MP 3B5 Phone: 46758570 Fax: 4675695 Trench Limited Power Line Carrier Division 85 Middlefield Road, Unit 6A Scarborough, Ontario Canada MV P9 Phone: 4698544 Fax: 469558 Trench France S.A. 6, Rue du Général Cassagnou B.P. 70 F68 St. Louis, Cedex France Phone: 333 897033 Fax: 333 8967663 Trench Germany GmbH Nürnberger Strasse 99 D96050 Bamberg Germany Phone: 499580 Fax: 49958034 Trench Switzerland AG Lehenmattstrasse 353 CH408 Basel Switzerland Phone: 46355 Fax: 46355900 Trench (UK) Limited South Drive Hebburn Tyne & Wear NE 3 UW Phone: 44948347 Fax: 44940633 www.trenchgroup.com E 3.8 Subject to change without notice (05.006) Printed in Canada.