Megger MTO106-NL – Transformer Ohmmeter

• MTO106, Only instrument, no accessories
• 48 V test voltage for fast saturation of transformers
• Multimeter type operation, intuitive and fast
• Safety through automatic, passive discharge circuitry

The MTO106 transformer ohmmeter is an easy-to-use, line-operated instrument specifically designed for safe and accurate field measurement of winding resistance in smaller transmission and distribution transformers.

It has dual channels with a wide measurement range and can accurately provide information about the vast majority of power transformers, reactors, and instrument transformers. The test current can be manually set in five different ranges to fit transformers of various sizes.

The instrument is exceedingly simple to use, which minimizes the need to train service engineers. It has a single selector switch for the test current and a single button to activate the test cycle. The instrument is also supplied with test leads fitted with Kelvin clamps that allow for a single, one-time connection to the unit under test. The test leads are 10 m (33 ft) in length to allow for easy testing of pole-mounted transformers.

The compact and lightweight instrument is housed in a rugged plastic case for true portability. When closed, the case is rated IP67, which means your instrument will always arrive safely to the testing location even in the harshest conditions.

Users are protected by an automatic discharge function that de-energizes the transformer winding at the end of every test. The discharge function is passive and thus also functions if there is an inadvertent loss of power or if the test or mains leads are accidentally pulled.

Applications

The MTO106 is mainly intended for field measurements of smaller transmission and distribution transformers:

• To verify factory test readings
• As part of a regular maintenance program
• To help locate the presence of defects in transformers such as increased contact resistance in terminal connections and tap changers

The instrument can also be used for general resistance measurements including control wiring, voltage regulators, motors, generators, and all types of connections.