RACOM RipEX2, Руководство пользователя

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COM port
The COM port needs to be Enabled and a Protocol needs to be selected to transfer any data. "Trans-
parent" type of COM protocol is dedicated for Bridge mode purposes. This protocol transfers data
between the COM port and the RipEX2 network transparently. Any other Protocol can be selected
when needed.
When the "Transparent" protocol is selected, all frames received from the COM port are broadcasted
over the radio channel and transmitted to all COM ports on all radio modems within the network. If the
remote COM port is also configured for "Transparent" protocol, the received data are transparently
transmitted over the COM port.
Terminal Servers
Behavior of Terminal Servers is similar to COM port. "Transparent" protocol needs to be selected when
transparent data transfer to whole network (broadcasts) is needed. The other protocol types can be
used for "Router mode" type of addressed communication.
5.1.1. Functionality example
In the following, common acronyms from SCADA systems are used:
• FEP - Front End Processor, designates the communication interface equipment in the center
• RTU - Remote Telemetry Unit, the terminal SCADA equipment at remote sites
The single digits in illustrations are “site names” and do not necessarily correspond with actual addresses
of both the RipEX2's and SCADA equipment. Address configuration examples are given in the
Sec-
tion 5.1.2, “Configuration examples” .
Step 1
Polling cycle starts:
FEP sends a request packet for RTU C through COM to
the connected RipEX2.
Step 2
RipEX2 FEP broadcasts this packet on Radio channel.
RipEX2 C and RipEX2 A receive this packet.
RipEX2 B does not receive this packet, because it is not
within radio coverage of RipEX2 FEP .
RipEX2 Radio modem & Router – © RACOM s.r.o. 40
RipEX2 in detail