Transformer insulation level L175 AC35 / 5 What does it mean
The voltage withstand voltage is 480kV, the power frequency withstand voltage is 200kV, the middle voltage side of the neutral point of the lightning impulse withstand voltage is 250kV, power frequency withstand voltage is 95kV; low side of the terminal side of the lightning Impact withstand voltage is 75kV, power frequency withstand voltage is 35kV;
3, "LI 75 AC 35" means that the 10kV transformer high voltage winding lead side of the lightning impulse withstand voltage is 75kV, power frequency withstand voltage is 35kV.
2, the insulation level of the transformer is according to the high pressure, medium voltage, low voltage winding sequence listed in the tolerance voltage value (the impact level in the former), during which separated by a slash. The neutral insulation level of the graded insulation is followed by a horizontal line at its wire end insulation level.
Such as: LI850AC360-LI400AC200 / LI480AC200-LI250AC95 / LI75AC35.
Meaning: 220KV three-side insulation of the main transformer, high-voltage side of the lead-side lightning impulse withstand voltage is 850kV, power frequency withstand voltage is 360kV, high-voltage side of the neutral point of the terminal lightning impulse withstand voltage is 400kV, power frequency resistance The voltage is 200kV;
1, the transformer winding rated withstand voltage with the following letter code:
LI - Lightning impulse withstand voltage
SI - Operating impulse withstand voltage
AC - power frequency withstand voltage
