Parabolic Reflector is an ultrasonic sensor for use when detecting partial discharge activity on exposed insulating surfaces. The reflector increases the sensitivity of the sensor allowing detection to be effective at up to 100m. It is commonly used in outdoor switchyards to detect surface discharge on string and post insulators, sealing ends and other exposed equipment.
Use of Parabolic Reflector
With the Parabolic Reflector connected to the PD-SGS, the reflector should be pointed at the HV equipment being inspected. Look through the view finder with both eyes open and line up the red dot visible through the view finder with the centre of the inspection area.
The PD-SGS/PD Detector instrument should be operated in AE Mode (See PD-SGS/PD Detector Operation Manual) and it will register a dB reading on the user display. It will also generate an audible output according to the level of activity detected.
It is recommended that when using the Parabolic Reflector out of doors, the headphones are worn in order to minimise interference from outside noise sources. Owing to the nature of acoustic PD detection and natural variations caused by environmental conditions, it is recommended that PD levels identified are appraised according to their relative values when compared with other similar plant and not in absolute terms.
Maintenance and Servicing
- If necessary, clean the equipment with a damp cloth. Do not use solvents as this may damage the surface.
- After use, the equipment should be disassembled and stowed in the carrying case.
- Replace low batteries immediately with a new cell of the type CR2032 3V. The battery box is situated on the lower surface of the red dot sight.
|Measurement Distance ||100 metres
|Measurement Range||-6dBμV to +70dBμV
|Measurement Gain||With suitable detection distance,|
|measurement gain||With suitable detection distance,
measurement gain is 18 to 20 dB
|Transducer Center Frequency||40 kHz
|Transducer Sensitivity||-65dB min at 40 kHz (0dB = 1 volt/μbar RMS SPL)
|Recommended Load Impendence||1MΩ
|Transducer Diameter ||16 mm