Home

Home

OTIWTI AB is manufacturing in Sweden, high quality transformer temperature indicators to the world market.

OTIWTI products are designed, manufactured and tested for operatation in harsh, substation environments in all different climates for decades.

Download bulletin 100E in English. Other languages under downloads.

Read more about the way to monitor transformer temperature in the Technical Application Description

Check also the NEWS!

Introduction.

Temperature is a prime parameter deciding for the use of life of transformer. Insulation is the most sensitive material and its temperature is directly related to the Winding temperature that in turn is related to the load of the transformer and on the Oil temperature as oil is the cooling media.

The IEC Guide gives no value for expected life but a reference temperature at 98°C of the hottest spot in contact with cellulose is assumed to give a “normal” life. The temperature increment causing the degradation rate to double is assumed to 6 K.

Considering these facts its obvious how important it is for the protection of a transformer to be equipped with reliable and accurate Oil and Winding Temperature Indicators.

To provide them is the OTIWTI mission.


 

OTIWTI Instruments

  • Instruments from OTIWTI AB are designed for power transformers to meet all
    environmental requirements.
  • OTI´s and WTI´s designed and manufactured to operate for decades, to match a transformer’s life.
  • Using liquid filled bellow technique, for maximum operating force. Non pressurized measuring system minimizes risk of leakage.
  • Up to five independent microswitches for control of cooling equipment, alarm and trip function
  • Optional analogue outputs for remote readings.
  • Winding temperature functionality (thermal image) inside the enclosure, meaning no heating element in pocket.
  • Large visible dial with black text and pointer on white background.
  • All components are made of non corroding materials to withstand long time outdoor use in tropical as well as arctic climates