A Pragma Group Company

Partial discharge sensors

Capacitive Couplers

Capacitive Couplers



RFCT’s

RFCT’s



rtdmodule

RTD Module



bush

Bushing Sensors

   

A wide range of partial discharge sensors are available from EDI depending upon the best bandwidth and frequency response required for the application. Sensors are available to monitor all electrical applications including medium and high voltage motors, generators, cables, transformers and switchgear.

Capacitive Couplers

80 pF capacitive couplers have historically been utilised for motors and generators at the line terminals. These devices can also be installed in switchgear and cable applications for detecting partial discharge in the cable and switchgear line up. These sensors are normally installed during scheduled outages as part of a new or refurbishment process.

RFCT’s

RFCT’s (Radio Frequency Current Transformers) are installed in the ground circuits of a variety of electrical equipment to measure partial discharges (PD). Typical applications include: cable terminations, splices, motors and large power transformers. On cable terminations, the grounded shield termination is passed through the RFCT, prior to the connection to ground. This will allow one to “look” down the cable.

RTD Module

Used on Motors and Generators to detect PD that may be occurring deeper in the winding that cannot be detected by sensors installed at the terminations. The RTD itself and the lead wire act like an RF antenna deep in the winding. Using both line sensors such as coupling capacitors and RTD sensors provides more coverage of the winding insulation system. RTD Modules are non-invasive so can be installed on-line and are available in 3 or 6 RTD format.

Bushing Sensors

These sensors are installed on bushing capacitor/potential taps. These sensors are used to monitor and detect problems with the bushing and winding insulation systems. Both the power frequency current from the bushing tap and the PD signals from the bushings and/or winding are detected. This allows one to periodically or continuously monitor bushing insulation Tan delta and Capacitance as well as partial discharges that may be produced due to bushing and transformer insulation defects.

For more information contact Martec or visit the EDI website.