The power must switched off and the installation must disconnected before performing this test ensure that the test voltage will not applied other equipment electrically connected the circuit tested, particularly devices sensitive voltage surges.5 1.
3. easurements There are main measurements required: Earth Continuity Insulation Tests protective devices
2. Chapter this standard describes the requirements for testing the compliance installation. also facilitates preventive maintenance installations, preventing serious faults which might prove expensive (production shutdown, etc. 2. The resistance measured must lower than threshold specified the standard applicable the installation tested, which usually the resistance value low, the resistance the measurement leads must compensated, particularly very long leads are used. When the method not applicable, however, other methods can used. isual inspection guarantee that the installation complies with the safety requirements (presence earth electrode, protective devices, etc. The electrical testing divided into parts: 1.
1. The test carried out using measurement instrument capable generating no-load voltage (DC AC) with minimal current 200 mA. There are many methods for measuring the earth, some more suitable than others, depending the neutral system, the type installation (residential, industrial, urban, rural, etc. According the IEC 60364 standard, the minimum insulation resistance values must follows: Rated voltage circuit secondary switchboard main switchboard Less than equal 500 including main switchboard Greater than 500 test voltage 250 500 1,000 Insulation resistance 0. TESTS PROTECTIVE DEVICES Fuses Circuit-breakers
To check the specifications the protective devices such fuses circuitbreakers, fault loop impedance measurement carried out calculate the corresponding short-circuit current. there earth electrode, may endanger people's lives and damage electrical installations and property. the purpose electrical installation testing primarily ensure that people and goods are kept safe and are protected the event fault.0 1. The IEC 60364 standard and its various national equivalents published each European country, such 15-100 France VDE 100 Germany, specify the requirements concerning electrical installations buildings. guarantee people's safety with regard these installations and the electrical equipment connected them, standards have naturally been developed and updated take changes into account. earth
To guarantee safety residential industrial electrical installations, there must earth electrode. This why the standards cover not only the initial verifications when installations are commissioned, but also periodic testing whose frequency depends the type installation and equipment, its use and the legislation the country involved. insulation
Good insulation essential prevent electric shocks. addition, the tests must carried out with measurement instruments that comply with the IEC 61-557 European standard ensuring user safety and reliable measurements.
- Residual current devices (RCDs)
RCDs, which detect earth leakage currents, can tested using two methods: basic test, also called pulse test, which determines the trip time (in milliseconds) step test, which determines the trip time and trip current, thus detecting any RCD ageing.) and does not show any visible evidence damage.0
4. This measurement, usually carried out between active conductors and the earth, involves injecting voltage, measuring the current and thus determining the insulation resistance value.), the possibility cutting off the power, the area available for planting stakes, etc. The effectiveness the safety measures implemented can only guaranteed regular tests prove they are operating correctly. When large enough area available set stakes, you should measure the earth with the traditional 3-pole method, also known the method.
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. visual inspection can then used check that the sizing correct.ELECTRICAL TESTING AND SAFETY
Electrical installation testing
The risks linked incorrect use electricity may include: -life-threatening danger for people, -threat damage electrical installations and property, -harmful effects systems operation and equipment life spans.). CONTINUITY
The purpose continuity measurement check the continuity the protective conductors and the main and supplementary equipotential bonds
