XL4 Plus RTU comms options

XL4 Plus RTU Comms Options

A recent investigation demonstrated the flexibility and power of the XL4 Plus RTU comms options.

The new rural water scheme is planned for a remote part of NZ. The aim is to add up to ten new telemetry sites over two separate zones.

Hydraulically, the water scheme interconnection is relatively straightforward with a maximum of 11km between sites. This range is well within the capability of all telemetry radios. The terrain however is very challenging with multiple hills, ridges and a forest preventing traditional options of communicating via a repeater or directly to the base station/SCADA server. The existing water treatment plant has good base comms over a data radio link.

The investigation considered a combination of store and forward between RTUs, master slave networks, cellular comms, and the low power QDR RS232 radio links.

The initial proposal is to have only two XL4 Plus RTUs communicate to the base station via data radios. One zone will use a master slave layout, as a high elevation site can see both the repeater and the local slave RTUs.

A high-speed Ethernet radio link is to be explored for the second zone. This will give the ability to store and forward multiple times along a chain of RTUs. Ethernet is the ideal mechanism for this as it is low latency and minimises any timing issues.

Cellular comms with the high speed 4G CM910 was also investigated. Unfortunately, cellular signal coverage was weak for two of the largest sites. This may well improve in the future with the roll out priorities in the Governments rural strategy document and independent plans by the Telco’s.

The water scheme’s telemetry communications plan can be reviewed later if needed, as converting to 4G cellular is straight forward.

The RTU comms options are all selected and configured in the QTech Workbench.

We encourage you to also review this application note for further details on this technique, together with important considerations.

Please contact us if you need assistance with any of the XL4 Plus RTU comms options.