The OMU is a completely passive optical measurement unit. It provides combined optical current and voltage measurement which can be interfaced to electronic meters and/or relays in high voltage substations.
The OMU combines the technologies for current and voltage sensing into a single phase unit which is light weight and compact in size.
The reduced size and increased accuracy of the OMU relative to conventional oil-filled current and voltage transformers make the design particularly well suited for the addition of revenue metering to existing substations where space may be a premium.