Mini-catalog · EN — Two-page mini-catalog spread covering the 3EK7 SL medium-voltage surge arrester family rated per IEC 60099-4. It tabulates the complete electrical characteristics for 14 ratings from 3.0 kV to 42 kV rated voltage (10 kA nominal discharge current, Qrs 1.2 C, Qth 4.5 kJ/kVr) with residual voltages across seven impulse shapes, the matching mechanical characteristics (height, creepage, withstand voltages, SSL/SLL loads, weights), the ordering-code breakdown with accessory options, and a dimensional drawing.
This mini-catalog extract (pages 20–21 of the 3EK medium-voltage surge arrester catalog) documents the 3EK7 SL series, a family of medium-voltage surge arresters designed and rated according to the IEC 60099-4 standard.
The series spans 14 ratings from 3.0 kV to 42 kV rated voltage. Every rating shares a common protection class: 10 kA nominal discharge current, a charge transfer rating Qrs of 1.2 C, and a thermal charge transfer rating Qth of 4.5 kJ/kVr. All types carry the SL designation and a rated short-circuit current of 20 kA.
The table lists, for each rated voltage, the continuous operating voltage, the full arrester type code, and the maximum residual voltages measured at discharge currents across seven impulse shapes — two switching-type impulses (30/60 µs at 125 A and 500 A) and five lightning-type impulses (8/20 µs from 1 kA to 20 kA). All residual voltage values are in kV.
| Ur (kV) | Uc (kV) | Arrester type | Designation | In (kA) | Qrs (C) | Qth (kJ/kVr) | 30/60µs 125 A (kV) | 30/60µs 500 A (kV) | 8/20µs 1 kA (kV) | 8/20µs 3 kA (kV) | 8/20µs 5 kA (kV) | 8/20µs 10 kA (kV) | 8/20µs 20 kA (kV) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3.0 | 2.4 | 3EK7 030 - 5 C B 4 | SL | 10 | 1.2 | 4.5 | 6.2 | 6.6 | 7.0 | 7.6 | 8.0 | 8.6 | 9.8 |
| 6.0 | 4.8 | 3EK7 060 - 5 C B 4 | SL | 10 | 1.2 | 4.5 | 12.5 | 13.2 | 14.0 | 15.2 | 15.9 | 17.1 | 19.7 |
| 9.0 | 7.2 | 3EK7 090 - 5 C C 4 | SL | 10 | 1.2 | 4.5 | 18.7 | 19.8 | 21.0 | 22.8 | 23.9 | 25.7 | 29.5 |
| 12 | 9.6 | 3EK7 120 - 5 C D 4 | SL | 10 | 1.2 | 4.5 | 25.0 | 26.3 | 28.0 | 30.4 | 31.8 | 34.2 | 39.3 |
| 15 | 12.0 | 3EK7 150 - 5 C D 4 | SL | 10 | 1.2 | 4.5 | 31.2 | 32.9 | 35.1 | 38.0 | 39.8 | 42.8 | 49.2 |
| 18 | 14.4 | 3EK7 180 - 5 C E 4 | SL | 10 | 1.2 | 4.5 | 37.4 | 39.5 | 42.1 | 45.7 | 47.7 | 51.3 | 59.0 |
| 21 | 16.8 | 3EK7 210 - 5 C F 4 | SL | 10 | 1.2 | 4.5 | 43.7 | 46.1 | 49.1 | 53.3 | 55.7 | 59.9 | 68.8 |
| 24 | 19.2 | 3EK7 240 - 5 C H 4 | SL | 10 | 1.2 | 4.5 | 49.9 | 52.7 | 56.1 | 60.9 | 63.6 | 68.4 | 78.7 |
| 27 | 21.6 | 3EK7 270 - 5 C H 4 | SL | 10 | 1.2 | 4.5 | 56.2 | 59.3 | 63.1 | 68.5 | 71.6 | 77.0 | 88.5 |
| 30 | 24.0 | 3EK7 300 - 5 C H 4 | SL | 10 | 1.2 | 4.5 | 62.4 | 65.8 | 70.1 | 76.1 | 79.5 | 85.5 | 98.3 |
| 33 | 26.4 | 3EK7 330 - 5 C J 4 | SL | 10 | 1.2 | 4.5 | 68.7 | 72.4 | 77.1 | 83.7 | 87.5 | 94.1 | 108 |
| 36 | 28.8 | 3EK7 360 - 5 C J 4 | SL | 10 | 1.2 | 4.5 | 74.9 | 79.0 | 84.1 | 91.3 | 95.4 | 103 | 118 |
| 39 | 31.2 | 3EK7 390 - 5 C J 4 | SL | 10 | 1.2 | 4.5 | 81.1 | 85.6 | 91.1 | 98.9 | 103 | 111 | 128 |
| 42 | 33.6 | 3EK7 420 - 5 C K 4 | SL | 10 | 1.2 | 4.5 | 87.4 | 92.2 | 98.2 | 107 | 111 | 120 | 138 |
Mechanical data is given row-for-row against the same 14 ratings, from the 170 mm housing (3.0/6.0 kV) up to the 510 mm housing (42 kV). It covers creepage distance, withstand voltages, the specified short-term load (SSL) and specified long-term load (SLL) — each quoted for the arrester alone and with insulating bracket — plus weight, flashover distance, and the applicable insulating-bracket size.
| Height H (mm) | Creepage distance (mm) | Is (kA) | Lightning impulse withstand 1.2/50µs (kV) | Power frequency withstand, wet, 1 min (kV) | SSL arrester only (N) | SSL with ins. bracket (N) | SLL arrester only (N) | SLL with ins. bracket (N) | Approx. weight w/o accessories (kg) | Flashover distance (mm) | Insulating bracket size |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 170 | 372 | 20 | 104 | 49 | 2940 | 470 | 2050 | 320 | 1.5 | 180 | short |
| 170 | 372 | 20 | 104 | 49 | 2940 | 470 | 2050 | 320 | 1.6 | 180 | short |
| 200 | 485 | 20 | 122 | 57 | 2500 | 400 | 1750 | 280 | 1.9 | 210 | short |
| 240 | 605 | 20 | 144 | 67 | 2080 | 330 | 1450 | 230 | 2.3 | 248 | short |
| 240 | 605 | 20 | 144 | 67 | 2080 | 330 | 1450 | 230 | 2.4 | 248 | short |
| 270 | 775 | 20 | 166 | 77 | 1850 | 290 | 1290 | 200 | 2.8 | 286 | long |
| 300 | 900 | 20 | 184 | 86 | 1660 | 260 | 1160 | 180 | 3.2 | 318 | long |
| 400 | 1230 | 20 | 242 | 113 | 1250 | 200 | 870 | 140 | 4.0 | 418 | long |
| 400 | 1230 | 20 | 242 | 113 | 1250 | 200 | 870 | 140 | 4.1 | 418 | long |
| 400 | 1230 | 20 | 242 | 113 | 1250 | 200 | 870 | 140 | 4.2 | 418 | long |
| 470 | 1420 | 20 | 281 | 131 | 1060 | 170 | 740 | 110 | 4.9 | 484 | long |
| 470 | 1420 | 20 | 281 | 131 | 1060 | 170 | 740 | 110 | 5.0 | 484 | long |
| 470 | 1420 | 20 | 281 | 131 | 1060 | 170 | 740 | 110 | 5.1 | 484 | - |
| 510 | 1595 | 20 | 302 | 140 | 980 | 150 | 680 | 100 | 5.4 | 520 | - |
The ordering code encodes the arrester's configuration. Using the example 3EK7 360-4CH4: '3EK7' identifies the medium-voltage surge arrester family, '360' the rated voltage of 36 kV, '4' the LD class 1 (a '5' in this position indicates LD class 2), 'C' the IEC standard, 'H' the housing type (H = 400 mm), and the final '4' alternating sheds.
Accessories are appended after a '-Z' suffix. In the example 3EK7 360-4CH4-Z M11 P12 M81: 'M11' is a line clamp (M = line terminal), 'P12' a NEMA insulating bracket, and 'M81' a bird protection cap.
| Code position (example 3EK7 360-4CH4-Z M11 P12 M81) | Meaning |
|---|---|
| 3EK7 | Medium-voltage surge arrester |
| 360 | Rated voltage = 36 kV |
| 4 | LD class 1 (5 = LD class 2) |
| C | IEC |
| H | Housing type (H = 400 mm) |
| 4 | Alternating sheds |
| -Z | Indicates accessories follow |
| M11 | Line clamp (M = line terminal) |
| P12 | NEMA insulating bracket |
| M81 | Bird protection cap |
The dimensional drawing shows the shedded arrester housing with M12 terminal studs at both ends, each with a 36 mm stud length, an overall housing height H (per the mechanical characteristics table, 170–510 mm depending on rating), and a shed diameter of 119 mm.
Click any figure to enlarge.