Designed specifically for carrying out fast non-invasive online partial discharge (PD) surveys in MV and HV substations, Megger’s new UHF Partial Discharge Detector measures PD activity at frequencies above those of common disturbances. This allows it to deliver accurate and dependable results for a wide range of assets, including cable-end terminations, surge arrestors, voltage transformers and isolators.
The compact, handheld instrument features a large colour touchscreen for easy operation and has dual-channel capability that allows direct comparison of the results obtained from two types of UHF sensor or from two phases. It is compatible with a wide range of sensors and, in addition to its primary UHF functionality it can also be used to perform RF PD measurements.
High bandwidth operation at UHF, in conjunction with phase resolved partial discharge (PRPD) pattern display facilities enable the new instrument to discriminate between different types of defect. This is an important benefit as it means, for example, that corona and surface discharges can be readily distinguished from dangerous internal partial discharge events that suggest a need for immediate further investigation.
In addition to operation via its integral touchscreen, the instrument can also be operated from an accessory keypad. Menus and settings have been kept to a minimum, and users are guided through the entire measurement process. The instrument is powered by a rechargeable battery that provides an operating time of at least ten hours – more than a working day – when fully charged.
As standard, the new Megger UHF Partial Discharge Detector is supplied with a dipole antenna for UHF surveying. Inductive (HFCT) and capacitive (TEV) sensors for making measurements on MV cables and switchgear are available as optional extras. A UHF PD coupling sensor can also be supplied, so the instrument can be used to carry out detailed and precise measurements on HV components such as terminations. As an additional benefit, this sensor is suitable for systems rated at up to 500 kV.