W-PD6 Partial Discharges Monitoring System
The term “partial discharge” is a common name for small electrical discharges (arcs) that typically occur within or between insulation materials—usually across a void in the insulation. Partial discharge is also referred to as corona or surface tracking. The visible evidence of corona presents itself as white, powdery residue, typically found on the end windings of motors or generators. Surface-tracking damage appears as tree-like, jagged lines, typically found on switchgear and bus ducts. Surface tracking stems from a contaminated insulation surface, often started by corona. The small arcing activity on the surface of the insulation contributes to further burning, resulting in additional stress points that promote further deterioration. Both corona and surface tracking are the primary causes of insulation breakdown, which can lead to full discharges and electrical failures. It is important to note that traditional methods of detecting corona and surface-tracking damage require taking equipment offline. It also requires disassembling the equipment—a costly procedure. Moreover, corona and surface tracking damage have to be severe to be visible. The W-PD system allows you to detect partial discharge while the electrical system is energized. It does so by detecting and analyzing the radio signal frequencies emitted by the partial discharges. More specifically, the W-PD focuses on the 1 MHz to 20 MHz bandwidth range where the majority of partial-discharge activity can be detected. W-PD allows predictive analysis and maintenance as opposed to preventive analysis and time-based maintenance.
The W-PD is a continuous partial discharge monitor that can be applied to a variety of medium voltage electrical equipment rated 4 kV to 38 kV. It is commonly applied to motors, generators, switchgear, bus duct, unit substations and cable systems. The W-PD will monitor the quality of insulation while the equipment is in service under normal operating conditions. Through monitoring, it can ascertain the relative condition of insulation, the deterioration of which is the leading cause of electrical failures. The W-PD system consists of sensors and a monitor. The monitor can be used as a stand-alone unit, or it can be wired so that it can remotely upload data to your system or to diagnostics personnel for analysis. While the sensors vary according to application, they are all designed to detect partial discharges—the foundation of the W-PD technology and one of the best predictors of insulation breakdown.
The software for W-PD6/W-PD60 provides the following functionality:
• Measurement data storage in database;
• Device configuration;
• Communication to a device;
• Data presentation and analysis.
The software is a part of PN5000 and can be part of GenGuard information analysis system. The software is supplied on CD and the user has unlimited licenses for use of the software. Please, read End User License Agreement to understand terms and conditions.The W-PD6/W-PD60 are normally pre-configured for a particular customer and application to the best knowledge that existed at the time of shipment. The configuration is stored in the provided template database which is customized for each order. Therefore, the more accurate the information for each particular application provided to Haozhi, the fewer configuration changes may required on site.