Transformer & Motor accessories


As electricity is distributed from power plant to the end-user there is a need to transform the voltage from one level to the next below. This transformation takes place using power and distribution transformers. Connecting cables to the transformers requires a wide range of transformer accessories like:

Bucholz relays

When gas is generated inside a transformer, it is a sure sign that something is wrong. To detect the gas, a Buchholz relay triggers an alarm and disconnects the transformer.  The relay also reacts if an oil surge greater than the preset value occurs.


When we say bushings, we talk about the whole range of porcelain-, epoxy- and silicon-bushings.

The whole program is produced according to international standards, such as DIN, CENELEC, ENEL, UNEL, BS etc.

The list of products looks like this:

  • Porcelain-bushings for indoor- and outdoor applications. We deliver the complete bushing, including arcing horn, all gaskets, clamps etc.

  • Epoxy plug-in bushings for oil-filled transformers or SF-6-gas-applications

  • Bushings with plug connection with silicon rubber protection for outdoor use for connections with bare electrical wire.


Breathers are used on oil-filled equipment to prevent moisture being sucked in during thermal expansion or contraction of the insulating fluid in the conservator. 

Any air movement is made to pass over silicagel crystals, which immediately remove moisture.  We have a large range of sizes for different oil volumes. 


When constructing a transformer, it is vital to ensure that excess pressure can be released in a controlled way.

Temperature control units

Winding temperature indicators where the sensor comprises a heat sensitive resistive circuit through which passes a current.  The thermometer can be fine-tuned via the potentiometer on the indicator dial.

Oil temperature indicators designed to measure the temperature of the insulating oil in the transformer. 

They can be supplied with a side-facing or front-facing terminal box with or without fixing bracket (flange), and can be fitted with up to four changeover micro-switches for control of cooling or for operating alarm and trip circuits.

Temperature control units can be fitted with a digital device used for printing out temperature.  4 PT 100 temperature sensors can be connected to the MB103 temperature control unit.  Data is stored for later retrieval and temperatures can be set for triggering alarm/trip circuits.

Tap changers

There are two kinds of tap changers: those for distribution transformers, and those for power transformers.

  • Ease of installation (reduced number of spare parts)
  • Speed of operation
  • Positive contact location after switching (high degree of security that you have switched the contact)
  • Compact dimensions
  • Accommodates variation in tank wall thickness (high degree of flexibility towards you as a customer)

Oil level indicators

The magnetic oil level gauges are commonly fitted into power transformer conservators to give both a visual indication of oil level and provide a minimum and maximum facility.

  • Range: 140 mm, 220 mm and 340 mm diameter.
  • For distribution transformers we supply 3 oil level indicators:
    • L60 (vertical for cover mounting, see picture)
    • L80 (magnetic movement)
    • L100 (magnetic movement)





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