The RMO-A is a portable micro-ohmmeter designed for contact resistance measurements of switchgear during manufacturing, commissioning and maintenance stages. This micro-ohmmeter is widely used by medium and high-voltage circuit breakers manufacturers. Other typical applications are testing of disconnecting switches, high-current bus bar joints, cable splices, and different high-current links. It accurately measures not only in factory environments but also in high-induction fields and substations
The RMO-A series contains 6 models, rated from 100 A (RMO100A) to 600 A (RMO600A). The RMO500A (formerly CPM500) is our best seller, with 500 A ripple-free current and weighs only 8 kg.
Although placed in a very portable and lightweight metal housing, RMO-A micro-ohmmeters have very high output power capabilities. They can generate 600 A test current continuously for up to 20 s. You can test with current up to 100 A without rest time. High output voltage enables a wider measurement range at the highest test currents, as well as the use of thinner/longer test cables. For testing with 100 A, 20 m test leads can be provided with only 16 mm2 cross-section.
RMO-A micro-ohmmeter generates a true DC ripple-free (less than 1 %) current with automatically regulated test ramps. During a test, the RMO-A ramps up with increasing current before measuring and decreasing current after the measurement. This significantly decreases magnetic transients and ensures great accuracy.
An additional option is a built-in High Precision module suitable for measurement of very low resistances, ranges from 1 to 30 µΩ, with 0,01 µΩ resolution.
These instruments can store up to 500 measurements in internal memory. A built-in thermal printer is available as an option.