W-PD2 Bushing Monitoring System
W-PD2 is a stand-alone microprocessor-controlled monitoring devicespecially designed to monitor the Gamma value in 60/50 Hz sets of bushings (25Hz is also applicable), to store the information in its internal memory and toprovide an alarm signal based on Gamma-parameter characteristics at an earlystage of insulation degradation.
• Calculations of capacitance and relative Tanδ of each bushing in a three-bushing set;
• Determining temperature coefficients of Tanδ of each bushing;
• W-PD2 has a temperature input for hot oil temperature allowing revealbushing characteristics temperature dependencies;
• W-PD2 has several interfaces that allow for easy implementation intoan alarm or SCADA system;
• One form-C dry relay contact providing “Red” alarm and device malfunctionindication;
• 4-20 mA optically isolated (or 0-5 V non-isolated) output representsparameter Gamma to SCADA system;
• Optically isolated RS-485 (optional RS-232) interface allowing for deviceconfiguration and data download into PC. RS-485 interface based on ModBusRTU protocol allows for networking with an existing ModBus network;
• PD ports provide for measurement of partial discharges on periodical basis withany appropriate external PD instrumentation.
• Gamma, Gamma’s phase angle, temperature coefficient and trend;
• Diagnostics – Bushing’s Tanδ and capacitance;
• Input signal’s magnitudes;
• Date and Time stamp and temperature at the measurement
• Alarm status;
• Communication to device from PC via RS-232 link or local RS-485 network orphone modem;
• Data downloading and storage for multiple devices;
• Device setting;
• Data analysis and presentation.
