Video: PD PROFILER – Product

Video transcript

A partial discharge monitor that stays on the switchgear, listens all day, and tells you what it found in numbers a maintenance team can act on. Partial discharge is how medium voltage insulation announces that it is failing. It starts at the weak points: cable terminations, joints, the bushings of a dry-type transformer. It is inaudible and invisible, and by the time it can be seen, the failure has usually happened. The secondary substations where most of this

equipment lives are rarely monitored at all. The PD Profiler is a monitor, not a survey instrument. It is installed on the asset, with strong magnets or on a DIN rail, without switching anything off, and it stays there. Four or 8 sensor inputs, and each input carries two measurement channels at once: ultrasonic and high frequency. It listens through two kinds of sensor. The SonoTEV Pro combines an ultrasonic microphone and a

transient earth voltage sensor in one magnetic housing, and one model serves both inside and outside a metal enclosure. The HFCT clamps around an earth conductor and picks up the high frequency current that a discharge sends to ground. What it produces first is the pattern every partial discharge specialist reads: the discharges plotted against the phase of the mains voltage. This is diagnostic grade data. Two clusters, one on each half cycle, are the signature of an internal defect.

Because a pattern is hard to trend and hard to hand to someone who is not a specialist, the monitor extracts a handful of indicators from it. Four of them describe the state of the insulation, and a change in any of them over weeks is what an alarm is built on. A substation is an electrically noisy place, and a monitor that cannot tell noise from discharge gives false alarms until nobody trusts it. So every channel has selectable filters, the gain adjusts itself, and a reference sensor on a non-monitored structure

captures the interference so that it can be gated out. What comes out of it. A local indicator on the unit, a dry contact for the substation, and the data over Ethernet to whatever you already run: Modbus TCP, a REST interface, MQTT for cloud platforms, or the manufacturer's own cloud with e-mail alarms. And it scales. Units chain together on one cable that carries power, phase synchronisation and the alarm, and on one Ethernet lead.

One supply, one network connection, and a whole row of switchgear is covered. The same monitor covers the assets that fail most often in a distribution network: switchgear and ring main units, dry-type transformers, cable terminations, and the equipment of a high voltage substation. The numbers that matter for a specification. Partial discharge monitoring, from Amperis.