ENR-JXB series transformer neutral point gap grounding protection complete set of equipment
1.Overview
110kV,220kV,and 330kV are the main voltage levels in the power supply system,and their neutral points are generally grounded directly.Due to requirements for relay protection setting configuration and prevention of communication interference,as well as to limit single-phase short-circuit current,some transformers adopt a neutral point non-grounding method.Under this operation mode,lightning strikes,single-phase grounding short-circuit faults,etc.can cause overvoltage at the neutral point.Moreover,most transformers are graded insulated,so overvoltage poses a great threat to the insulation of the neutral point,and protective devices must be installed to prevent accidents.
In China's 110kV-330kV power system,the neutral point protection of transformers primarily employs a parallel operation of lightning arresters and protective gaps.This constitutes the complete set of transformer neutral point gap grounding protection equipment,also known as the main transformer neutral point grounding assembly.
II.Model Description
III. Working Principle
IV. Ordering Instructions
1. Voltage level of transformer
2. The transformation ratio, accuracy class, and capacity of the current transformer
3. Rated current of the isolating switch and its operating mechanism type
4. Is a pillar required
