What is the communication network?
The communication network is the data path that links the HMI, the SCADA servers, the PLCs and the CCRs, carrying commands down and status and alarms back up.
The communication network is the data path that joins the layers of the control system: the HMI clients, the SCADA servers, the PLCs and the CCRs. Commands travel down it and status, alarms and readings travel back up. It is built from switches and gateways, with fibre between buildings, copper Ethernet inside a room or cabinet, and serial or bus links to some field devices.
It carries information only; the lamp current runs on the series-circuit cable, which is a separate cable with separate routing and tests. Networks are often laid as a ring or dual path, so one cable break or switch failure leaves another route and the sites stay connected. If a site is cut off, the screen can be out of date while the PLCs and CCR local control remain, so the real status is checked at the CCR or in the field. The network is normally segregated and secured because it commands lighting pilots rely on.
Frequently Asked Questions
Q1What is the communication network in airfield lighting control?
It is the data path that links the control layers: the HMI clients, the SCADA servers, the PLCs and the CCRs. Commands travel down it and status, alarms and readings travel back up. It carries information only, not the power that lights the lamps.
Q2What cables and media does it use?
Commonly fibre-optic cable between buildings, copper Ethernet inside a room or cabinet, and serial or fieldbus links to some devices, joined by switches and gateways. Fibre is favoured over long runs because it is not affected by electrical noise or differences in earth potential. The actual choice is set by the project design.
Q3Why use a ring or a dual path?
So one cable break or switch failure does not cut off a site. In a ring, traffic that cannot take the broken link goes the other way round, and a dual path gives a second route. The failure is still reported, so the damaged link can be repaired.
Q4How is the network different from the series circuit cable?
The series circuit cable carries the lamp current from the CCR through the isolating transformers to the lights. The communication network carries data only. The two use separate cables, routes and tests, and the network is routed and protected as the design requires.
Q5What happens if the network fails?
That depends on the design. Redundant paths keep most faults invisible to the operator, but if a site is cut off the screen can become out of date. The PLCs and local control at the CCR remain available, so check the real status at the CCR or in the field and follow the failure flow.
Q6Why is the network kept separate and secured?
Because it commands lighting that pilots rely on. It is normally segregated from other airport and office networks, with access control and user levels, and only authorised personnel make changes, under the airport's change-control procedure.
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