RTU
Remote Terminal Unit. An IED used specifically for interfacing between a computer and other devices. Sometimes may include control, monitoring, or storage functions.
electricalscho
Root-Mean-Square
The effective value of alternating current or voltage. The RMS value equates an AC current or voltage to a DC current or voltage that provides the same power transfer.
ROCOF
Rate of Change of Frequency.
RMU
Ring Main Unit.
RJ-45
Registered Jack 45. Connectors used to connect computers to LANs or phones with many lines. It is able to house up 8 wires that is twice as many wires as the RJ-11.