Nomal Type Suspension Insulators
0102030405
120KN Disc Suspension Porcelain Insulator - U120B Type
product description
Electrical Ratings (Minimums per IEC 60383):
Power Frequency Withstand Voltage (Wet): Typically 45-50 kV
Power Frequency Withstand Voltage (Dry): Typically 70-75 kV
Lightning Impulse Withstand Voltage (1.2/50 µs wave): Typically 100-115 kV
Application
● Used worldwide in suspension and tension strings for medium and high-voltage AC overhead transmission and distribution lines, particularly where IEC standards are followed.
● Multiple units are connected in series to provide the necessary insulation for the line voltage and operating environment.
● The 120 kN rating makes them suitable for lines with moderate to heavy mechanical loads, including standard transmission lines, lines with significant conductor weight or span length, and potentially some lighter angle or dead-end applications.
String Configuration Example
500kV AC: 28-32 discs
±800kV HVDC: 40-45 discs
Dead-end Strings: 10% additional discs vs. suspension strings
Inspection Interval: 2-5 years (depending on environment)
Critical Checks:
Cracks >10mm in porcelain
Galvanization wear on hardware
Cement line deterioration
Replacement Indicators:
5% reduction in mechanical strength
Multiple damaged discs in a string
specification
| Ball and socket type suspension porcelain insulators( IEC Class ) | ||
| Type | XP-120 | |
| IEC Class | U120BL | |
| Coupling size | 16 | |
| Dimensions | ||
| Diameter(D) | mm | 255 |
| Spacing(H) | mm | 146 |
| Leakage distance | mm | 320 |
| Mechanical Values | ||
| Combined M&E strength | kn | 120 |
| Impact strength | N.m | 10 |
| Routine proof test load | kn | 60 |
| Electrical Values | ||
| power frequency dry withstand voltage | kv | 70 |
| power frequency wet withstand voltage | kv | 40 |
| Dry lightning impulse withstand voltage | kv | 100 |
| Power frequency puncture voltage | kv | 110 |
| Radio influence Voltage Data | ||
| Test voltage RMS to ground | kv | 10 |
| Maximum RIV at 1000kHz | μv | 50 |
| Packing and Shipping Data | ||
| Net weight,approximate | kg | 5.6 |