Network operators can now get faster and significantly more reliable information about the quality and the condition of their cables. This is made possible thanks to the brand-new 50 Hz Slope Technology. For the first time, it has become possible to immediately locate faults in underground cables during the actual PD measurement.
With the 50 Hz Slope Technology for the first time, a withstand test with VLF cosine-rectangular voltage (VLF CR) and PD diagnosis with damped alternating voltage (DAC) is combined in one unit. This allows an efficient and integrated solution for precise inventory of the network infrastructure. The important fact here is that the PD measurement data, gained with the VLF CR or with the DAC test voltage, can be compared directly with the 50 / 60 Hz network voltage. This facilitates reliable decision making.
Component failure in a substation has serious repercussions. It has the potential to cause injury, damage and unplanned outages, which result in significant disruption and cost. Predictive condition assessment aims to identify faults developing in electrical equipment so that they can be addressed before failure.
The UHF PD Detector is the ideal tool for quick, non-invasive surveys in MV and HV substations and should be part of the toolkit for all maintenance and service teams. Due to its high measurement bandwidth, the UHF method provides accurate local online partial discharge (PD) measurements on HV components such as cable end-terminations, surge arrestors, voltage transformers and isolators.
Dual measurement channels allow two phases or two types of UHF sensors to be compared, which further increases the scope of use of the UHF Detector. MV switchgear surveys can also be carried out using the radio frequencies in combination with the wide selection of TEV and HFCT sensors. The phase resolved PD pattern (PRPD) display helps to identify type of defect and, importantly, differentiate the noise from the PD signal. Noise can affect PD readings, leading to a false interpretation of the results and unnecessary component replacement. The noise handling capability of the Megger UFH PDD ensures a true reading of PD, eliminating false positives, so only failing component are identified for replacement.
The handheld unit can either be operated using a keypad or using the large 6” colour touch-screen. It has a battery life of over 10 hours. Its mix of features and performance make the UHF detector the most cost effective unit of its kind.