Skip to main content


The TAPTRANS is an 8-gas on-line transformer DGA monitoring unit designed to monitor the transformer and OLTC (On-Load Tap-Changer). The TAPTRANS can individually measure the Main, Selector and Divertor tanks in one unit. The photo-acoustic detection system used by the TAPTRANS allows measurement of high and low gas levels without the need for extensive recalibration/cleaning. The TAPTRANS measures all significant fault gases (in ppm) as outlined by international standards as well as moisture in oil (%RH & ppm). The measurement of these gases allows the user to detect and diagnose a complete range of transformer and tap-changer faults (including overheating and over tapping).



  • Monitor the main, selector and divertor tanks in one unit.
  • Medium/High/Critical risk and/or consequence of failure.
  • Industrial – Oil & Gas, Chemical plants and heavy industry.
  • Generation, Transmission, Distribution Transformers and OLTCs.


  • Complete solution – monitor Main, Selector and Divertor tanks in one unit.
  • Transformer faults detected in their infancy, minimizing costly unplanned outages and equipment failure.
  • Transformer output optimized safely, maximizing your assets.
  • Photo Acoustic Technology – no costly consumables/calibration gases required.
  • Transformer ageing can be calculated.
  • Complete monitoring and diagnostics of transformers from results.
  • Designed for field use – global installation by almost all major utilities.
  • Single unit used to monitor a three phase bank or multiple transformers.
  • Tapchanger outages can be minimized by planning maintenance based on dissolved gas concentrations.


  • DGA & Water – Eight gases (hydrogen, methane, ethane, ethylene, acetylene, carbon monoxide, carbon dioxide and oxygen) plus moisture and nitrogen calculation. 8-gas monitoring of multiple tanks in a single unit.
  • 8-gas monitoring of main, selector and divertor tanks in a single unit.
  • Inputs/Outputs for additional sensors including load and temperature.
  • Easy Installation – Simple, straightforward procedures.
  • Hourly Sampling – Real-time DGA results down to once per hour.
  • Perception – PC software allows downloading, trending and analysis of results.
  • Communication Options – Extensive local and remote communications options.
  • Alarm Settings – Sophisticated programmable alarm system.
  • Acceleration of sampling rate – automatic increase in sampling rates if gas concentrations exceed caution or alarm settings.
  • Minimal Maintenance – Reduces expense and inconvenience for user.

Download Kelman TAPTRANS Fact Sheet (PDF, 1,08 MB)