Bushing Monitoring System

Transformer bushing failures sometimes occur outside the capacitive layers, where traditional analysis of leakage currents will not give indication of an internal problem. When the utmost in transformer reliability is required for critical transformer assets, partial discharge detection must be part of the monitoring strategy. The TransMAX 2000 performs all the test methods of the ZVCM-1001 but also monitors for partial discharge (PD). The PD activity in the bushings is monitored in parallel with the power factor calculations. PD is detected using the same bushing sensor as with the ZVCM-1001, there are no other sensors or Rogowski coils. PD is caused by defective insulation in high-stress areas, movement of energized parts, or design errors where lowlevel discharges occur. Some types of PD may not present a problem, but others can develop into surface tracking or insulation failure, which can lead to bushing or transformer failure. The TransMAX 2000 also has the unique capability of monitoring GIC events and trends which potentially could damage the transformer. Easy-to-use MultiTool software works with both the TransMAX 2000 and ZVCM-1000. Additional Specifications TransMAX 2000 Power Supply Input Operating Range 85-264 VAC, 120-370 VDC, 50 VA PD Frequency HF <20 MHz PD Resolution 1.0° Time Resolution 10 nS Dynamic Range 65 dB PD Intensity 0 – 5000 mW PD Amplitude 0.02 – 100 nC ± 10 V Top oil temperature sensor input Three load current CT sensor inputs Ambient Temperature and Humidity sensor inputs USB port for ZTZ software configuration, commissioning and data analysis RS-485 port for SCADA access Modbus RTU or DNP 3.0 Serial Ethernet port remote access via ZTZ Software, SCADA access over Modbus TCP or DNP over Ethernet Outputs PF, C1, leakage current for each bushing Imbalance for each group of 3 bushings PD power, PD amplitude, PD pulse count for each channel PRPD plots for each channel Top oil temperature Load currents Hot-Spot temperature Ambient temperature and humidity