3EP1 Surge Arrester. Metal-oxide surge arrester without series gaps for high-voltage systems up to U m. = 170 kv

Transcription

1 3EP1 Surge Arrester Metal-oxide surge arrester without series gaps for high-voltage systems up to U m = 170 kv Rated voltage up to 180 kv Nominal discharge current 10 ka, 8/20 µs Line discharge class LD1, LD2 High current impulse 100 ka, 4/10 µs Standards IEC99-4, First Edition, ANSI / IEEE C other standards on request Pressure relief capability 40 ka Siemens AG 10.96

2 3EP1 Surge Arrester Metal-oxide arrester without series gaps for high-voltage systems up to U m = 170 kv Application The MO arrester 3EP1 protects the insulation of equipment in electrical systems against external and internal overvoltages. It is available with rated voltages of up to 180 kv. The nominal discharge current is 10 ka. Each unit of the 3EP1 is equipped with very quickopening pressure relief diaphragms and gas diverter nozzles (6) at both ends. In the extremely rare event of an arrester overload, these diaphragms already open at a pressure which is only a fraction of the porcelain housing strength. The emitted jets of gas are then directed towards one another, due to the shape of the gas diverter nozzles, such that the arc continues burning outside the housing until it is cut off. The standard 3EP1 design is for use under normal operating conditions in accordance with the specified standards. Special designs for use under special operating conditions are possible. Special arresters are also available for the overvoltage protection of the star point and the tertiary winding of transformers, where required. In addition, we can provide you with various arrester connections to suit your particular requirements. For inquiries please use the attached questionnaire or contact your nearest Siemens office. Explanation The housing sizes specified in the column minimum housing size (Tables 1 and 2) are the smallest feasible sizes for the relevant rated voltages. Larger housings can also be selected where e.g. a longer creepage distance or a higher housing insulation withstand level is required (see Table 3 for data). The rated voltages specified in Tables 1 and 2 are examples. In general, arresters can be supplied with any rated voltage, up to the specified maximum value. The electrical data must be determined through interpolation of the table values (minimum housing length on request, where required). Structure In its electrically active part, the 3EP1 comprises a stack of metal-oxide resistors (1) with a non-linear voltage-current ckaracteristic. The resistors are clamped between the flanges of the housing, by means of a strong pressure spring (2). Cross-section of a unit The flanges are produced from a light metal alloy which is resistant to open air and seawater, and are cemented with the porcelain housing (3). This connection procedure ensures optimal power transmission between flanges and porcelain and allows high permissible mechanical forces acting on the top section. Special emphasis is put on the sealing system. Weather and ozone-resistant synthetic rubber seals (4), corrosionresistant pressure relief diaphragms (5) and carefully selected material combinations which have proved successful for many years ensure that the housing is leakproof.

3 Typ 3EP1-1 / LD1 Nominal discharge current (IEC) : 10 ka 8/20 µs Line discharge class : 1 Energy absorbing capability : 3,5 kj per kv rated voltage Long duration current impulse : 500 A; 2000 µs Voltage-time-characteristic : Diagram 1 IEC99-4, First Edition, Rated COV Maximum values of the residual voltages at discharge currents of the Min. housing voltage [U r ] [U c ] following impulses size 30/60 µs 30/60 µs 8/20 µs 8/20 µs 8/20 µs 1/2 µs 500 A 1000 A 5 ka 10 ka 20 ka 10 ka kv kv kv kv kv kv kv kv I I I I I I II II x I I + II I + II x II x II x II Table 1 Selection of frequently used rated voltages Typ 3EP1-1 / LD2 Nominal discharge current (IEC) : 10 ka 8/20 µs Classifying current (ANSI /IEEE) : 10 ka 8/20 µs Line discharge class : 2 Energy absorbing capability : 4,3 kj per kv rated volatge Long duration current impulse : 500 A; 2000 µs voltage-time-characteristic : Diagram 2 IEC99-4, First Edition, ANSI / IEEE C Rated COV Maximum values of the residual voltages at discharge currents of the Min. housing voltage [U r ] [U c ] following impulses size 30/60 µs 30/60 µs 8/20 µs 8/20 µs 8/20 µs 1/2 µs 500 A 1000 A 5 ka 10 ka 20 ka 10 ka kv kv kv kv kv kv kv kv I I I I I I II II I + II I + II I + II x II x II x II Table 2 Selection of frequently used rated voltages

4 Housings for the 3EP1 arresters Min. Breaking moment acc. to DIN 48113: 2,1 knm Housing Housing insulation withstand Creepage Figure Height Diameter of Pressure Maximum size level distance the grading relief arrester ring capability weight* Power frequency Lightning H d withstand voltage impulse with- 50 Hz, 1 min. stand voltage dry 1,2/50 kv kv mm Nr. mm mm ka kg I II x I I + II x II Table 3 *The maximum weight can vary depending on rated voltage and line discharge class Bolt terminal 3EX6 120 Cr Ni Figure 1 10 thick Foot flange Cross-section A-B, Figure 2 Figure 2 Flat terminal 3EX6 121 hot-dip galvanized steel Possibilities of the isolated mounting Ground plate 3EX6 124 with insulating feet Ground plate 3EX6 125 with insulating feet Porcelain post insulater 3EX6 127 We reserve the right to change any figure, value or weight without notification. Figures not guaranteed.

5 Power frequency voltage versus time characteristic 1,3 Diagram 1 1,2 1,1 1 A B 0,9 0,8 0, A Preheated to 60 C, loaded with rated energy B Preheated to 40 C, without load t [s] U...temporary overvoltage Ur...rated voltage 1,3 Diagram 2 1,2 1,1 1 A B 0,9 0,8 0, A Preheated to 60 C, loaded with rated energy B Preheated to 40 C, without load t [s] U...temporary overvoltage Ur...rated Voltage

6 Information sheet for surge arrester Please direct any enquiries to your nearest Siemens Regional Office or to the address indicated below (where the form may also be sent when completed) Arrester type : 3EP1 3EP2 3EP3 3EQ2 Not yet defined From Company : Department : Name : Address : Tel. : Fax : Power system data Rated system voltage kv or maximum voltage for equipment U m kv Earth fault factor (if known ) δ 1,4 1,4 < δ < 1,7 δ = 3 Earth fault duration (if known) < 10 sec > 10 sec or type of neutral earthing Direct Low-resistance Arc-suppression coil (earth fault compensation) Technical specifications of arrester required (where known) Rated voltage kv Line discharge class LD1 LD2 LD3 LD4 LD5 Creepage distance mm Short-circuit strenght (pressure relief current) ka Installation altitude (if over 1000 m) m Seismic withstand capability Bolt or flat-type terminal? For 3EP1 only : If insulated installation desired, state type of installation in accordance with catalog data sheet 3EP1 (See possibilities for insulated installation ) 3EX EX EX6 127 Any other data Siemens AG Power Transmission and Distribution Group High Voltage Division Arrester and Limiters Siemens AG, EV HBA4 D Berlin Fax ++49 (30)