TransformerGuard ® PD Monitoring system A Complete Partial Discharge Monitoring System for Transformers The Doble Lemke TransformerGuard is a monitoring system for assessing the condition of transformers in the field. The system is an on-line partial discharge (PD) monitoring system for power transformers. By monitoring the in-service partial discharge, the insulation performance can be reliability assessed over time and corrective action can be taken before a failure occurs. True to form, the Doble Lemke TransformerGuard provides all the tools necessary to install a permanent online monitoring system for a single transformer, but can also be expanded to include the bushings or other transformers. Doble supplements our system by providing the support for commissioning, calibration and analysis. You’re never alone with Doble. TransformerGuard complies with all IEEE and IEC standards on partial discharge testing. Features Highly Sensitive UHF PD Detection By using UHF sensors, PD sources can be sensed within the transformer without obstructions. By mounting the UHF sensors within the tank, the tank wall effectively screens out external interference. Advanced Analysis Tools Using internationally recognized algorithms approved by IEEE and IEC, the best possible diagnosis of fault conditions can be realized. These tools include Phi-V-N, Phi-V and Phi-N displays. Alarming setpoints can be setup from the beginning and modified over time as the transformer's normal operating conditions are learned. Scalable The PD Evaluation Server can act as the central hub to one or several PD-Guard / UHF monitors. Each PD-Guard has its own unique IP address to identify it on the network. The unit can be upgraded to Doble TransformerGuard bushing PD sensors. include TransformerGuard Computer(s) for Computer(s) for Remote Control Remote Control & Analysis & Analysis UHF Plate Sensors UHF PD Sensor (Mounted in Hatch) for Plates/Hatch LAN / WAN / Internet LAN / WAN / Internet PD Monitoring PD Monitoring Server Server Software Software Rugged and Reliable Central to TransformerGuard is the rugged PD-Guard/UHF monitor that makes physical connection to the sensing points. This system complies with IP65 industry standards and can survive the harshest environments to include direct spray. Condition Based Maintenance Given its online diagnostic capabilities, and ability to set alarms, the system can provide advanced notification of impending failure. Better decisions can be made earlier. Interference Rejection By using UHF technology, external noise is effectively removed. In addition the unit measures between 100 to 1000 MHz, thus localized the detection to the transformer, not the surroundings. Choice of UHF Sensors Based on the facilities available, up to 4 UHF sensors can be connected to one PD-Guard/UHF. If additional sensors are needed, additional PD-Guards can be added to the network. UHF sensors are available for DN50 and DN80 drain valves (straight pass other values acc. to customers request) or hatch mounting. UHF Drain Valve UHF Drain Valve Sensors Sensors Fiberoptic Fiberoptic Ethernet Switch Ethernet Hub LAN LAN PD-Guard/UHF PD-Guard/UHF

Why use the Doble TransformerGuard? TransformerGuard gives early warning to partial discharge damage within the transformer while the unit operates under normal conditions. The software monitors trends in magnitude and repetition rate, and if this exceeds a preset condition, an alarm is set alerting the owner to a possible problem. TransformerGuard fits well within a condition based maintenance program. PD detection is accepted by industry experts, IEEE and IEC as one of the key diagnostics for transformer equipment, and can be used as an integral part of asset risk management. Transformers are...

The “Complete Package” We don’t deliver parts, we deliver the whole package. TransformerGuard is composed of a suite of products that are optimized for deep winding fault analysis and diagnosis without compromising the reliability of the apparatus. Key components and services included in TransformerGuard are: The Doble PD-Guard/UHF & UHF Probes At the heart of TransformerGuard is the highly compact, rugged, and light-weight Doble PD-Guard/UHF. This provides all inputs necessary to monitor the partial discharge from UHF probes mounted in drain valves and hatch covers. The PD-Guard/UHF is a ULTRA...

Key Specifications* PD-Guard /UHF • Display and transmission of PD history in real time • PD magnitude as peak or average value • PD current • Noise rejection • Frequency and domain signal conditioning • Easy alarm setting can be configured for each measuring channel separately PD Evaluation Server & PD-Guard Analysis Software • Display and transmission of PD history in real time • PD magnitude as peak or average value • PD magnitude weighted to the IEC 60270 characteristic • Noise rejection • Frequency and domain signal conditioning • Easy alarm setting, can be configured for each measuring...