Description
U120B Porcelain Disc Insulator Drawing and Specifications
| IEC Class | U120B | U160BM | U160BL | U210B | U240B | U300B |
| Coupling size | 16 | 20 | 20 | 20/24 | 24 | 24 |
| Diameter (mm) | 255 | 280 | 280 | 280 | 280 | 280 |
| Spacing (mm) | 146 | 155 | 170 | 170 | 170 | 195 |
| Creepage distance (mm) | 320 | 350 | 380 | 380 | 405 | 390 |
| Combined M&E strength (kN) | 120 | 160 | 160 | 210 | 240 | 300 |
| Impact strength (N.m) | 10 | 10 | 10 | 11.3 | 11.3 | 11.3 |
| Routine proof test load (kN) | 60 | 80 | 80 | 105 | 120 | 150 |
| Power frequency dry withstand voltage (kV) | 70 | 75 | 75 | 75 | 75 | 75 |
| Power frequency wet withstand voltage (kV) | 40 | 42 | 42 | 42 | 45 | 45 |
| Dry lightning impulse withstand voltage (kV) | 100 | 110 | 110 | 110 | 110 | 130 |
| Power frequency puncture voltage (kV) | 110 | 110 | 110 | 120 | 120 | 130 |
| Test voltage RMS to ground (kV) | 10 | 10 | 10 | 10 | 10 | 10 |
| Maximum RIV at 1000kHz (kV) | 50 | 50 | 50 | 50 | 50 | 50 |
| Net weight,approximate (kg) | 5.6 | 7.4 | 7.8 | 10.4 | 11.1 | 14.3 |
