Testing Facilities

STRI’s large test hall can be divided into two test bays enabling different tests to take place simultaneously.

The test halls are provided with highly effective electromagnetic shielding, which gives a very low background level during PD and radio interference measurements.

STRI has equipment for handling SF6 gas and transformer oil.

Test Facilities w x l x h
High voltage test hall 25 x 37 x 30 m
High voltage test hall 18 x 36 x 21 m
High voltage test hall 18 x 18 x 20 m
High voltage test hall 10 x 13 x 12 m
Pollution test hall Ø18 x 23 m
Medium voltage test cells 10 x 10 x 5 m


Diagnostic Tools

STRI has sophisticated equipment for the measurement and registration of different parameters during tests such as:

  • Special photo and video equipment sensitive to UV-light study discharge mechanisms and corona
  • Power quality can be measured by different instruments to localize harmonics and variety of voltage variations
  • Electrical field strength can be measured at high potential with field probes developed by STRI.
 Outdoor Testing

STRI’s outdoor test area can be used for short and long term testing of, for example pre-qualification tests of cables.

Control Room

The different sets of test equipment are controlled from three special rooms. These receive their power supply via special isolating transformers to protect the measuring equipment and to ensure that accurate test data are obtained


Test Equipment

Test Ratings Remarks
Impulse Testing
Lightning Impulse Testing 2800 kV
Switching Impulse Testing (Wet/Dry) 1850 kV
AC Testing Wet/Dry 1050 kV/1.5 A 50 Hz single phase
550 kV/3.0 A 50 Hz single phase
430 kV/2.0 A 50 Hz 3-phase
DC Testing* Wet/Dry 1250 kV/0.3 A/2 A continuous current/pulses
Partial Discharge
& RIV Testing
Same voltage limitations as for AC test
Capacitance &
Tan d Testing
Same voltage limitations as for AC test
Temperature Rise Testing Up to 7000 A
* Higher values with bipolar test