Electromagetic field and line-conducted interference needs to be eliminated in order to measure low-intensity partial discharges with a PD background noise level (≤ 1 pC) in accordance with IEC 60270.
The effect of electromagetic field interference caused by radio signals, radar stations, welding arcs, etc. can be limited by a shielded room, also known as a Faraday cage.
Line-conducted interference caused by switching signals from thyristor switches and power switches, for example, can be dampened by means of high-frequency filters.
The design and size of the shielded rooms will be determined depending on the specific application. They are separated into a test and control room. Furthermore they are equipped with a PD-free lighting system, emergency lighting, and security loop. There is the option of equipping the room with air-conditioning and a crane, as well.
The high-frequency filters are used to filter the power and control input and the communications lines. The high-frequency filters are installed as close to the shielded rooms as possible to ensure optimal attenuation.
- Routine and type testing of cable and cable accessories
- The end-to-end concept including shielding, grounding, filtering, lighting, and additional accessories such as cranes and air-conditioning enables you perform sensitive PD measurements
- Reduction of the test time for the test object in the test bay thanks to optimally tailored layout (size of shielded room and number/position of doors, for example) with respect to the test object, material processing, and the test system