Accessories for smart transformers - eDevices

Pressure relief devices for smart transformers

Pressure in the transformer is one of the key health parameters that predict early signs of decreased performance or an upcoming failure. Overpressure in the transformer tank can lead to an explosion and a hot oil spill in the surrounding environment.

Choose our pressure relief device for smart transformers type ePRD type e170SC, an evolution of our conventional pressure relief devices, to continuously monitor and keep the pressure in the transformer under control. It can discharge the overpressure to the exterior in milliseconds and reduce the risk of tank rupture.

The device is equipped with a digital interface for easy connection to smart grid applications and can be integrated into a system through a central control unit. It is compatible with our complete eDevice family, can be connected also to third-party devices, and be part of our modular monitoring ecosystem for transformer diagnostics – MeDICA.

Contact us and get support with the product selection.

Why buy

  • A proven technology with robust design
  • Wide pressure range settings allow the adaptation to the volume of the oil in your transformer
  • Continuous online monitoring enables the end-users to adopt a condition-based maintenance approach and driving asset health management remotely   
  • Visual indicator enables easy on-site control of the operating status to the transformer operators
  • Bleed screw allowing the removal of air from the system, making it work more efficiently
  • Spring is designed outside of the transformer’s lid, which removes any moving part from the inside of the tank and allows the transformer designer to choose a simpler outline 
  • Easy installation
  • Maintenance-free


  • Smart grid applications
  • Liquid-filled transformers
  • Suitable for new installations and retrofits
  • Suitable for offshore environment
  • Suitable for tropical climates
  • Part of our MeDICA solution

Technical data at a glance

StandardIEC 60076-22-1
HousingAluminum alloy
InstallationIndoor, outdoor and Tropical proof
Ambient temperatureFrom -40°C up to +80°C
Solution for lower temperature available upon request
Oil-directed coverSeawater resistant aluminum, powder coated
GasketsNBR, Viton
Visual indicatorSeawater resistant aluminum, red color, and stainless steel stem
SwitchesUp to 3, Changeover
Cable glandM25x1.5 – nickel plate brass
Degree of protectionIP65
Power supply24 V dc ±10% polarized
Analog output4-20 mA
Digital outputModbus RTU
Data logger