Conventional accessories

Buchholz relays

Insulation liquid inside the transformer needs to be monitored to reduce any risk of transformer failure to a minimum. Buchholz relays to provide information about any internal malfunction indicated by gas accumulation in the liquid and keep oil flow speed monitored and under control.
Choose our solution and assure reliable and safe operation of the transformer and a power supply network. You will get a reliable product designed to promptly stop the system when necessary to prevent any catastrophic failure.

Contact us and get support with the product selection.

Why buy

  • Proven technology
  • Adjustable value settings for alarms and switches
  • Easy installation
  • Maintenance free


  • Liquid-filled transformers
  • Hermetically sealed transformers
  • Transformers with conservator with rubber bag
  • On-load tap-changers
  • Railway & Traction applications
  • Suitable for new installations and retrofits
  • Suitable for offshore environment
  • Suitable for seismic environment
  • Suitable for tropical climates

Additional accessories

Gas sampling device type GSD2


Technical data at a glance

StandardIEC 60076-22-1
HousingAlluminum alloy
Types of installation environmentIndoorCorrosion class: C4-MediumRAL 7032
OutdoorCorrosion class: C4-MediumRAL 7032
Tropical proofCorrosion class: C5-MediumGeomet coatings
Off ShoreCorrosion class: CXRAL 7035
Nominal pipe diameterDN25, DN50 and DN80 or G 1/2 threaded connection
Inspection glassTempered glass with UV filter
Oil temperatureFrom -40°C up to +120°C
Ambient temperatureFrom -40°C up to +80°C
Lower temperature available upon request
SwitchesUp to 4
Max. nominal current2A
Min. switching current10 mA/24 V dc (golden contact is available for lower current)
Rated insulation voltage2.5 kV ac 1 min between contacts and earth, 1.0 kV ac 1 min between open contacts
Flow vents speed10 m/s to 3.0 m/s (each +- 15%)
Cable gland1; M25x1.5
Degree of protectionIP65
IP66 available upon request
Mechanical test (vibration class)4M4 Class
4M6 Class available upon request

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