The RTU is capable of communicating with many devices either within the local sub-station or with a remote master station. The communication is via serial communication channels in the RTU or through the LAN ports.
The RTU is essentially configured to run as slave for communicating with one or more master stations. However, the RTU can also act as a master on a different communication channel for acquiring data from other devices like protection relays, etc.
Some of the protocols supported by the RTU for communication with a master station are –
- IEC 60870-5-101
- IEC 60870-5-104
- IEC 60870-5-103
- Modbus Master/Slave (RTU / TCP)
- DNP 3.0 Master / Slave (Serial / TCP)
The RTU supports multiple masters with separate database view for each master. The communication with master can be configured as dual redundant for redundancy in serial / LAN ports.
The RTU is capable of communicating with remote locations over the following networks –
- Full/Half-duplex PLCC modems
- Full/Half-duplex leased-line modems
- Full/Half-duplex dial-up modems (over PSTN, GSM, networks)
- Over GPRS networks provided by GSM mobile operators.