CABLE CLAMPS FOR LOW AND HIGH VOLTAGE CABLES

Transcription

1 CABLE CLAMPS FOR LOW AND HIGH VOLTAGE CABLES Bauteile für die Elektrotechnik GmbH An der Molkerei Kastellaun Phone Fax w w w. id-technik.com id-technik.com

2 Cable Clamps for Low and High Voltage Cables Series K Mechanical resistance to short-circuits: N Page 2 Type K 26/38 K 36/52 K 50/75 K 66/90 outer cable diameter mm mm mm mm Series KT Mechanical resistance to short-circuits: N Page 3 Type KT 25/39 outer cable diameter mm Series KR Mechanical resistance to short-circuits: N Page 4 Type KR 75/100 KR 100/130 KR 130/160 outer cable diameter mm mm mm Cable Clamps for bundled fastening of Low Voltage Cables Series KS Mechanical resistance to short-circuits: N Page 5 Type KS 25/36 KS 33/46 outer cable diameter mm mm Series KP Mechanical resistance to short-circuits: N... Page 6 Type KP 29/41 KP 39/53 KP 51/64 outer cable diameter mm mm mm Series KH Mechanical resistance to short-circuits: N Page 7 Type outer cable diameter KH 73/ mm KH 84/ mm KH 105/ mm KH 115/ mm Accessories... Page 8/9 S 57/92 Distance wedge for Cable Clamps KH 73/86 und KH 84/97 S 90/112 Distance wedge for Cable Clamp KH 105/117 Elastic Inlay: Fixation of cables and padding of cables Examples of Fastenings Page 10 Short-Circuit Tests Page 14

3 Cable Clamps Application: Material: Properties: Fastening of all types of single- and multi-conductor high and low-voltage cables. Polyamide, fiberglass-reinforced, coloured black, flame resistant, special protection against ultraviolet rays, free of halogenes, fully recycable Tensile strength: 120 N/mm 2 Flexural strength: 210 N/mm 2 Thermal expansion: 0.01 % per 10 C temperature increase Flame resistance: UL94V-O and classification following DIN 5510, part 2, flamability class S3 Resistance to: ultraviolet rays, ozone, oils, fuels,alkalis, radioactive rays Temperature range: Ambient temperatures Continuous operation Short heating Constructional Features: down to -40 C up to 120 C up to 220 C admissible The fiberglass-reinforced polyamide used in manufacture is marked by particularly high mechanical strength and heat resistance. Implementation both indoor and outdoor due to resistance to ageing, ozone and ultraviolet rays. No alteration in strength within a temperature range of -40 to 120 C. Thus particularly suitable for emergency operations of XLPE insulated cables. Because of its resistance to radioactive rays (at a radiation dose of 100 MRAD strength loss is less than 20 %) implementation is also possible in nuclear power stations. As the length of the clamping area is very wide the mechanical pressure on the cables is low. The dynamic forces of high short-circuit currents are very effectively withstood. Implementation can be done in those cases where high short-circuit currents occur. Therefore a secure fixation of the cables is insured and damage to them is being avoided. The fastening of cable clamps can be adapted to all local conditions. Test reports from neutral laboratories concerning dynamic short-circuit currents, up to 110 ka, and the fire-resistance of the material, are available. 1

4 CABLE CLAMPS Series: K Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single- and multi-conductor cables. 26 mm - 90 mm N 5 Nm Dimensions in mm Typ D Ø L B l d Ø H 1 H 2 h a K 26/ K 36/ K 50/ K 66/ D Ø : indicates the outer cable diameter range Example of fastening: Additional bottom parts for arrangement of several cables 2

5 CABLE CLAMPS Series: KT Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single- and multi-conductor cables 25 mm - 39 mm N 5 Nm Dimensions in mm Typ D Ø L B l d Ø H 1 H 2 h a KT 25/ D Ø : indicates the outer cable diameter range 3

6 CABLE CLAMPS Series: KR Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single- and multi-conductor cables 75 mm mm N 8 Nm Dimensions in mm Typ D Ø L B b l d H 1 H 2 h a KR 75/ KR 100/ KR 130/ D Ø : indicates the outer cable diameter range 4

7 CABLE CLAMPS Series: KS Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single-conductor cables in trefoil arrangement 25 mm - 46 mm N 5 Nm The assembly hole in the bottom part of Series KS permits direct fastening to lattice, concrete and wooden masts, suitable for M 10 bolts. (see: Examples Of Fastenings For Clamps) Dimensions in mm Typ D Ø L B l d H 1 H 2 h a KS 25/ KS 33/ D Ø : indicates the outer cable diameter range of each of the cables 5

8 CABLE CLAMPS Series: KP Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single-conductor cables in trefoil arrangement 29 mm - 64 mm N 8 Nm Dimensions in mm Typ D Ø L B l d H 1 H 2 h a KP 29/ KP 39/ KP 51/ D Ø : indicates the outer cable diameter range of each of the cables 6

9 CABLE CLAMPS Series: KH Application: For cables with outer diameters of: Mechanical resistance to short-circuits: Maximum initial torque for fixing screws: Fastening of single-conductor cables in trefoil arrangement 62 mm mm N 8 Nm Dimensions in mm Typ D Ø L B l d H 1 H 2 H 3 a KH 62/75* KH 73/ KH 84/ KH 95/107* KH 105/ KH 115/ D Ø : indicates the outer cable diameter range of each of the cables * Delivery times and minimum quantity per order on request 7

10 DISTANCE WEDGE FOR CABLE CLAMPS SERIES KH Application: For cables with outer diameters of: Material: Additional fastening of cables in trefoil arrangement, especially for vertical installations 57 mm mm Fiberglass-reinforced polyamide The surfaces are roughened D : Admissible range of outer diameters of the single cables using distance wedges if padded to D S. To achieve an optimum tightening, the cables have to be padded to the below shown outer diameters. Dimensions in mm cable clamp type D wedge type D S KH 62/ KH 73/ S 57/ KH 84/ KH 95/ KH 105/ S 90/ D D s 8

11 ELASTIC INLAY Application: Material: Padding of cables for elastic compressation of diameter variations caused by changes of load and ambient temperature Fixation of cables and support of weight in vertical installations One-side ribbed Neoprene Thickness: 5 mm Heigth of ribs: 2,5 mm Length: 100 mm, Also available in rolls lenght of 3 m Wide: 100 mm Examples for application: Torque for fixing screws: max. 20 Nm Important: Counternut with washer ( necessary for clamp series KR ) Elastic Inlay Torque for fixing screws: max. 20 Nm Distance wedge for additional fastening in KH clamps 9

12 - Examples of Fastenings For Clamps - Only KS Serie Bolt Size M 10 10

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16 Short-Circuit Experiments Test institute: Forschungsgemeinschaft für Hochspannungs- und Hochstromtechnik e.v. Hallenweg, Mannheim, Germany Date of test June 29, 1979 Parts tested: Test: Cable clamp, Model K 36/52 Fastening of individual singlecore cables Cable clamp, Model KP 39/53 Joint fastening of trefoils of single-core cables Experiments were meant to define the behaviour of cable clamps under dynamic strain applied by maximum shortcircuit currents up to 110 ka The following figures were assumed as admissible strain on cable clamps: Type K 36/52 maximum admissible strain = N Type KP 39/53 maximum admissible strain = N 2 I s F = 17,75 l a F l a I s : force applied by short circuit in Newtons : distance between clamps in meters : center-to-center distance between cables in meters : maximum short circuit in ka Test: Cable Clamp K 36/52 Three 10-KV single-core cables with cross-linked polyethylene insulation and cross sections of 400 mm² were laid out in parallel and fastened to a frame using the cable clamps in question. Test No. Is ka a cm /73 65,3 11,5 0, /74 80,2 11,5 0, l m F N Findings: Cable Clamps withstood forces of N and N without any damage. However, considerable bending of cables was observed. Photographs 1 and 2 show test set-up before and after testing. 14

17 Test: Cable Clamp KP 39/53 Three twisted 20-kV single-core cables with cross-linked polyethylene insulation and cross sections of 300 mm² were laid out in a U-shape and held in trefoil arrangement by the cable clamps. Test No. Is ka a cm /71 64,9 4,3 1, /72 64,3 4,3 1, /75 80,0 4,3 0, /76 81,3 4,3 1, / ,3 0, / ,3 0, l m F N Findings: Cable clamps withstood short-circuit forces of N to N without damage. Photographs 3 to 6 show the behavior of the trefoil during and after the surge. Tests revealed that closer spacing of clamps slightly reduces heights cable jump to. Considerable bending of cables between clamps was observed. Photographs 7 and 8 show the trefoil before and after tests /78 and /79. Here, as well, there is considerable bending of cables after two 110-kA surges, although the 44 centimeters between clamps is the spacing normally used in practice. In these tests, the cables jumped to heights of only 0,2 to 0,3 m. 15

18 Result of the tests: Besides the fact that the tested cable clamps meet the requirements placed on them, these experiments show that: 1. When using single-core cable, we recommend that the dynamic forces of the short-circuit current be considered as well, not only its thermic effects. 2. In order to prevent excessive bending of cables between clamps, the latter may have to be spaced closer together for high short-circuit currents than their maximum admissible strain would normally dictate. 3. With high short-circuit currents, simply arranging the cables in trefoil and laying them on racks, for instance, is not enough. As Photographs 3 to 6 show, the bundled cables can be damaged during jumps, or they may damage other system parts. In such cases, it appears expedient to connect the trefoil to the rack at appropriate intervals, bearing in mind that the rack itself must be able to withstand a certain amount of strain. However, these tests do not allow us to state how high such strain may be. 16

19 Photograph 1 Test set-up for tests /73 74 and 80 Photograph 2 After test /73 and 74 Max. short-circuit current: 65,3 ka and 80,2 ka Short-circuit force: N and N 17

20 Photograph 3 Test /72 During surge Max. short-circuit current: 64,3 ka Short-circuit force: N Photograph 4 Test /75 During surge Max. short-circuit current 80,0 ka Short-circuit force: N Photograph 5 Test /76 During surge Max. short-circuit current 81,3 ka Short-circuit force: N Photograph 6 Test /76 After test 18

21 Photograph 7 Test set-up for tests /78 and 79 Photograph 8 After test /78 and 79 Max. short-circuit current: 110 ka Short-circuit force: N 19