Winding Single Phase Resistance Meters – Overview

The RMO-TT series is designed for winding resistance measurement of inductive objects. It uses advanced switch-mode technology. It is an accurate (0,1% rdg + 0,1% F.S.), and powerful portable instrument (up to 100 A). It generates a true DC ripple-free current with automatically regulated measurement and discharging circuit. It can perform simple, quick and reliable transformer on-load tap changer condition assessments. This series enables measurements of a winding resistance in every tap position, current ripple values and transition times during the tap changes. Problems with the connection, contacts, and selector/diverter switch operation can be detected with these measurements. It is equipped with thermal and overcurrent protection. It has the ability to cancel electrostatic and electromagnetic interference that exists in HV electric fields. This is achieved by a proprietary filtration solution applied to both the hardware construction and the application software implementation. Applications include: winding resistance measurement of inductive test objects; dynamic resistance measurement (DVtest) of on-load tap changers; measurement of on-load tap changer motor current by using a dedicated channel; heat run test, which enables obtaining the Hot Spot temperature along with resistance graph during the cooling process 1; and single-phase automatic transformer demagnetisation.

Winding Single Phase Resistance Meters  – Features

• On-load tap changer dynamic resistance measurement
• Three resistance measurement channels
• Four temperature measurement channels
• Vibration measurement channel
• Tap changer motor current monitoring channel
• Automatic measurement for the Heat Run test
• Rapid automatic demagnetisation
• Automatic discharge circuit