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The series Of Full-Seal AC Three-Phase Combined Gapless Metal Oxide Arresters are mainly used in voltage system of 3kV, 6kV, 10kV & 35kV to protect the insulation between phasese and phases & ground of HV electric equipment, as a new-type combined overvoltage preventer to avoid the damages of atmospheric overvoltage & switching overvoltage.

Combined porcelain-coating metal oxide arresters has achieved successful experience since coming into being in the 1980s, especially used in protection HV motor from switching overvoltage. They effectively prevented motor insulation from the damages of overvoltage between phases and phases & ground. However, its large volume and difficult-mounting in switch cabinet limit their application. The AC three-phase combined composite insulation metal oxide motor arresters adopt special manufacturing process to intergrate arresters with insulators and keep same dimension with those of original arresters. This brings a great convenience to clients.

The series Of Full-Seal AC Three-Phase Combined Gapless Metal Oxide Arresters for voltage system of 3kV, 6kV, 10kV & 35kV are composed of 3 interphase arrester units, 1 phase-ground arrester unit and 2 insulators. Phase A and Phase C make 1 interphase arrester unit and 1 insulator integrated into one respectively. Phase B makes 1 interphase arrester unit and 1 phase-ground arrester unit intergraded into one.

Arresters with the core piled up by metal oxide nonlinear resistance cards & insulators, made into one by special process and sealed into silicon rubber by the new technology of once-pressing moulding, become integral one. Three-phase A, B & C arresters are installed connecting wire in its center. This is the best structure for combined composite insulation metal oxide arrester, in which all hardware is stainless steel and there are the following excellent characteristics:

1. Excellent external insulation property (high flashover voltage);

2. Anticorrosion, aging resistance, high temperature resistance, small volume and light weight;

3. Good flame resistance, strong resistance to soiling, excellent protective property.

4. Good silicon rubber moulding, reliable sealing;

5. Convenient mounting, small space.

The HV terminals of three phasese of arresters connect to phase terminals and 0 points in the middles of three arresters connect with each other by interphase wires, which forms “Y” connection, then the neutral point of the “Y” connection connects to arrester unit D in series, the lower terminal of arrester unint D connects to ground, which forms integral phase-phase & phase-ground protection system. So, in case of dangerous overvoltage for electric equipment insulation and atmospheric overvoltage appearing during operation, metal oxide nonlinear resistance cards restrain the overvoltage from the protected electric equipment.