Lightning Arrester Testing Service - Dubai - UAE

Carelabs is authorized provider of Electrical Installation’s Study, Analysis, Inspection, and Certification services in UAE, and offer lightning arrester testing service.

Lightning Arrester is the device used to protect the insulation and conductors from damaging effects of lightning on electrical power systems and telecommunication. Typical lightning arrester has a high-voltage terminal and a ground terminal. When a lightning surge travels along the power line to the arrester, electricity from the surge is diverted through the arrester to the earth.

If protection fails or is absent, lightning that strikes the electrical system introduces thousands of kilo volts that may damage the transmission lines, and can also cause severe damage to transformers and other electrical or electronic devices.

Monitoring Total Leakage Electricity

Presently the monitoring of total leakage electricity (capacitive and resistive currents) used by many utilities. The Leakage Electricity Monitor is used to measure the Leakage Current of Surge Arrester, and in case of high leakage current Surge Arrester is replaced. However, it is felt that this method is not the fool proof method as the total leakage current, which is purely capacitive, does not signify precisely the health of the Surge Arrester. There are the issues once the Surge Arrester has blasted even though total leakage current value was lower than the limit recommended by the manufacturers.

Resistive current is 15-30% of total current and since capacitive and resistive currents are at 90 degree face shift even reasonable change of resistive electricity results in very small increase in the total current. Hence observing total leakage electricity may not show degradation of ZnO disc. Degradation of long linear ZnO disc generally leads to harmonics in the leakage current when system voltage of fundamental frequency applied. Third consonant resistive electric measurement based on filtering of third harmonic element from the total leakage current. Leakage current of the order of about 500 micro amps is generally considered as safe.

The power loss can be checked by several methods given below:

• Using a voltage signal as reference
• Compensating the capacitive element by using a voltage signal
• Capacitive compensation by combining the leakage current of the three phases
• Third order harmonic analysis
• Direct determination of the power losses
• Third order harmonic analysis with compensation for harmonics in the voltage

Advance Monitoring System with Resistive Current Element calculations

The use of advanced diagnostic methods greatly decreases the chances of failure & avoids loses of man and money. It is desirable to check condition of Surge Arrester at regular time intervals, by measuring the resistive element of the continuous leakage current in service without decreasing energy of Arrester. Reliable measurements achieved by the instruments based on the principle of “Voltage Signal” as a reference. Regular monitoring of Lightning Arrester has prevented many failures in 66 kV to 765 kV substations. Advanced machineries promote testing even the Surge Arrester is in service, analysing with special current clip-on transformer leakage electricity in the Surge Arrester ground connection. The values of this current normally ranges from fractions of mille ampere to a few mille amperes entire characterized by a resistive current variations whose value is an indicator of deterioration of the Surge Arrester. Leakage of electricity increases due to different stresses like declining and Arrester failures.

Lightning Protection Systems Testing

Most building services would simply not function correctly if faults or defects were present but the correct operation of a lightning protection system only becomes obvious when it called upon to protect a structure. For this reason it is even more vital to make sure that fully trained and accredited engineers undertake regular testing and maintenance works on vulnerable structures and sites.

The current in a lightning strike is likely in the range of 2,000A – 200,000A and so an effective functional system is vital to make sure protection of assets. Majority of structures use BSEN 62305 to report their design, testing and maintenance works related to lightning protection. This standard states a “competent person” should carry out inspections so a good rule of thumb is to look for contractors with third-party accreditation of their ability to design and report on lightning protections systems.

As large parts of the lightning protection system may be hidden or inaccessible after completion, it is particularly important, and indeed necessity of the code, that each element of a lightning protection system should inspect during the construction stages of an installation. Special attention must give to any part of the system that will hide conceal upon completion. These elements may hide for aesthetic reasons or th.