The ultrasonic AA sensor detects airborne acoustic signals from PD into air, including corona (in outdoor substations) and surface discharges and tracking (in indoor air‑insulated switchgear (AIS).
It can be installed either inside or outside the switchgear panel, with a clear line‑of‑sight to the PD source.
The AA sensor is used in the HVPD’s MV AIS Switchgear Monitoring Solution in conjunction with the HVPD Kronos® Monitor and Linearplex™ expansion module. When there is a requirement for On-line PD monitoring of MV AIS, the AA sensors are daisy-chained inside and along the AIS switchboard, typically with one sensor per switchgear panel.