ANSI 52-3 High Voltage Suspension Porcelain Insulator Description
IEC Standard: ANSI 52-3 Suspension Insulator
Nominal Diameter: Typically 255mm
Spacing (Dry Arcing Distance): Typically 146mm
Mechanical Strength (M&E Rating – Combined Mechanical & Electrical): This is the defining difference. The U70N corresponds to a 70KN M&E strength rating.
Leakage Distance: Typically around 305mm
Electrical Ratings (Typical Values): Flashover performance is primarily dictated by these factors, not the mechanical rating.
1. Low-Frequency Dry Flashover Voltage: 80 kV
2. Low-Frequency Wet Flashover Voltage: 50 kV
3. Critical Impulse Flashover Voltage (Positive): 125 kV
4 .Critical Impulse Flashover Voltage (Negative): 130 kV
ANSI 52-3 High Voltage Suspension Porcelain Insulator Application:
Used in suspension and dead-end strings on medium and high-voltage AC and DC transmission and distribution lines.
Multiple units are connected in series to achieve the required insulation level for the system voltage and environmental conditions.
Crucially, 70KN U70B Disc Suspension Porcelain Insulator is selected over U40B units in locations where higher mechanical loads are expected. This includes:
1. Lines with heavier conductors.
2 .Longer spans between towers.
3. Areas with high wind or ice loading potential.
4 .Dead-end points and angle structures where conductor tension is highest.