The UR-7HH is a COMMS module for use with the UR Series of Multilin Universal Relay Systems. The inter relay communication characteristics of the UR-7HH include a 820 nm, multimode, LED, with 2 channels.  Each universal relay is featured with high-speed communication capabilities with a communication switch, an IEC Process Bus, and inter-relay communication abilities. The communication abilities make it seamless for a Multilin universal relay to integrate in to existing systems or infrastructures. There are three Ethernet ports available to combat heavy Internet traffic conditions and reduce any potential latency effects. The updated communications features are the IEC 61850 DNP 3.0 with a Modbus TCP/IP and IEC 60870-5-104 protocols. There are IEEE C37.118 synchrophasors as well over the Ethernet connection. 

The UR-7HH is a COMMs communication module that is one of many components in the UR Series of Multilin universal relay systems. The universal relays also contain a CPU, a CT/VT module, an I/O transducer module, a communication switch, and other components that allow the universal relay to serve as a comprehensive technological solution for end users. The dimensions of the horizontal UR relay are 18.974 by 6.960, advertised as a 19 inch relay.