DV Power RMO30T - DV Power RMO30T Winding Resistance OhmMeter on ElectricityMetering.com

The ohmmeter RMO30T is designed for resistance measurement of inductive test objects. RMO30T generates true, filtered DC current. Both injection of current and discharge of energy from the inductance is automatically regulated.

RMO30T injects current with a voltage as high as 60V. This ensures that the duration of test is as short as possible, and that the desired test current is reached as soon as possible. Two independent channels enable testing of two series windings, or primary and secondary windings. There is enough memory within RMO30T instrument to store 100 measurements. All measurements are time and date stamped.

The set is equipped with thermal and overcurrent protection. The RMO30T has very high ability to cancel electrostatic and electromagnetic interference in high HV electric fields. It is achieved by very efficient filtration. The filtration is made utilizing appropriate hardware and software. The RMO30T current output is rated at 30 A for 5 minutes, 20 A for 10 minutes and 10 A continuously.

On Load Tap Changers

RMO30T can measure the winding resistance of the individual taps of a power transformer’s tap changer, and can check whether the on-load tap changer (OLTC) switches without an interruption.

In the moment the tap is changed from tap to tap, the device detects the sudden, very short drop of the current flow. A properly working of tap changer differs from a malfunctioning one, e.g., an interruption during the change, by the magnitude of the ripple and slope values. An interruption will result in much higher ripple and slope values than a properly functioning of tap changer.

RMOWin-T

Using RMOWin-T software a test can be operated from PC, and the results can be obtained directly in PC. Using RMOWin-T the result can be printed like an Excel table which later can be shown as a diagram and used for a report.

Typical application of RMO30T is measuring the resistance of:

transformers
On-Load Tap Changers
generators and electrical motors
high-current busbar joints
cable splices

More Information

See the DV Power RMO30T Brochure