Sonus PD Alert

Online Permanent Partial Discharge Monitoring for Switchgear


Overview Image


The Sonus PD Alert is an asset-mounted device for indicating the presence of partial discharge in high voltage switchgear, ring main units (RMUs) and transformers. Designed for use in small substations, the instrument can activate local and remote alarms in addition to local indication. The Sonus PD Alert is built into a tough case that magnetically mounts to the RMU. Installation is very quick and simple with only a power connection required to get the system operational. Alarms can be configured to operate either locally with SCADA or remotely using an optional integrated modem. The system incorporates algorithms that distinguish noise from real PD, significantly reducing the likelihood of getting false alarms. The status and PD levels are displayed on a bright OLED display at the front of the unit.

Avoid Power Outages

Early warning about defects that can lead to failure

Cut Your Costs

Designed for large scale roll out across distributed assets, the monitoring system allows for a decrease in man-hours usually associated with inspection rounds.

Prevent Failures

Implement as part of a Condition Based Maintenance program to monitor assets and receive notifications to inspect for possible faults before failure strikes.


Part Number Sonus PD Alert
General Specifications
Overall Dimensions 210 x 190 x 65 mm (8.27 x 7.48 x 2.56in)
Weight 670g (0.66lb)
IP/ NEMA Environment Rating IP54 / NEMA 1 Standard, IP 68 Optional
Body Material Robust ABS case
Display OLED display with display level LEDs
Connectors Power, SCADA, 3x Ultrasonic, TEV
Control Membrane keypad
Operating Temperature -20°C (-4°F) to 60°C (140°F)
Humidity ≤90% RH non-condensing
Data Acquisition and Analysis
Number of Channels 4
Signal Sampling 320k Samples/sec, 10 bit
PD Analysis Automatic
Reporting Website or Standalone
TEV Specifications
Sensor Capacitive
Measurement Range 0 to 80 dBmV
Resolution and Accuracy 1 dB, +/- 1 dB
Noise Rejection Yes, with PRPD
Ultrasonic Specifications
Number of Channels 3
Measurement Range -6dBμV to + 70dBμV
Resolution and Accuracy 1 dB, +/- 1 dB
Transducer Sensitivity -65dB (0dB = 1volt/µbar RMS SPL)
Transducer Center Frequency 40 kHz
Rated Voltage 100 to 250 VAC
Frequency 47 to 63Hz
Internal Back-up Battery Lithium Ion, 3.7V, 6.9Ah, 35.5Wh
Back-up Operating Time 8 hours using Default Settings
Safety and EMC CE-compliant in accordance with Low Voltage Directive (2014/35/EU) and EMC Directive (2014/30/EU)
Warranty 12 Month Limited Warranty
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Product Resources

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