AQUARIA ELECTECH

GAPLESS METAL OXIDE LIGHTNING ARRESTERS /SURGE ARRESTERS Light Duty/ Heavy Duty/ Sub Station Class


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High voltage power systems experience over voltages, which are generated through occurrence faults, switching operations and lightning discharges. The duration & magnitude of these voltages vary depending on the type of surges. Under such voltage conditions, the insulation of the power system undergoes stresses that could lead to failure. Hence it is imperative that the power systems are protected from these over voltages at the time of occurrence. Using a device with variable impedence with respect to voltages can provide protection from over voltages. Such a device is a Gapless Metal Oxide Lightning Arrester which is connected in parallel to the system to be protected.

Product Range

3kV — 36kV

Type Tests

CPRI, Bangalore as per IEC 60099-4 (yr 2009) & IS 3070 Standards


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Application Areas :

High voltage power systems experience over voltages, which are generated through occurrence faults, switching operations and lightning discharges. The duration & magnitude of these voltages vary depending on the type of surges. Under such voltage conditions, the insulation of the power system undergoes stresses that could lead to failure. Hence it is imperative that the power system is protected from these over voltages at the time of occurrence. Using a device with variable impendence with respect to voltages can provide protection from over voltages. Such a device is a Gapless Metal Oxide Lightning Arrester which is connected in parallel to the system to be protected.

Switchgear panel enclosures :

Special Indoor arresters, installed close to the cable terminations, are usually used to protect medium voltage switchgear in air insulated systems. If the substation cell is connected with an overhead line, at the risk of a lightning strike, the nominal discharge current of these arresters should be 10kA (Line discharge class 1 ). This applies even if a 10kA arrester is already installed at the transition point between the overhead line and the cable.

Overvoltage protection of motors :

If HV motors are switched of during running condition, then they are at the risk from over voltages on account of multiple re-ignitions in the switch. These re-ignitions occur mostly if the current during switch-off is below 500 Amps. To protect these motors, over voltage arresters must be installed directly at the motor terminals or, alternatively, in the panels which are supplied with these motors or at the circuit breakers.

Cable sheath protection of HV Cables :

: In order to reduce losses along the cable, the cable sheath of high voltage single core cables are mostly earthed at one end only. The un-earthed end must then be protected with arresters against transient over-voltages. The critical selection criteria for these arresters is the voltage induced along the cable in the event of a short circuit. This voltage depends upon the cable geometry and the method in which it is laid in the cable duct, but generally it does not exceed 0.3kV per kA short circuit current and the km length of the cable.


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