Tap Changer Analyzer & Winding Ohmmeters

RMO-TW, TD and TT Series

The Tap Changer Analyzers & Winding Ohmmeters RMO-T series are designed for winding resistance measurement of inductive objects, and for a tap changer analysis. The RMO-T instruments are based on the state of the art technology, using the most advanced switch mode technology available today. The RMO-T instruments are accurate (0,1%), powerful (up to 100 A) and lightweight (7,5 – 15,5 kg). They generate a true DC ripple free current with automatically regulated measurement and discharging circuit.

RMO-T instruments can perform a simple, quick and reliable transformer on-load tap changer condition assessment. These instruments enable measurements of a winding resistance in every tap position, current ripple values (percentage of a current drop during a tap change) and transition times during the tap changes. Problems with a connection, contacts, and selector/diverter switch operation (tap change with interruption) can be detected with these measurements.

Typical application areas of the RMO-T are high-voltage substations and industrial environments. They are intended to measure the resistance of:

  • Transformer windings
  • On-load tap changers
  • Generators
  • Electrical motors
  • High-current busbar joints
  • Cable splices
  • Welding joints

RMO-TW series

Three-channel winding resistance measurement, one temperature measurement channel, demagnetization and tap changer verification.

RMO-TD series

RMO-TD series has all the RMO-TW features and also tap changer analysis (DRM) and OLTC motor current measurement.

RMO-TT series

RMO-TT series has all the RMO-TD features including additional temperature measurement channels.