VNF : to surf from lock to lock

Voies Navigables de France (VNF- French waterways -) is an industrial and commercial focus public organization in charge of managing, maintaining, and developing the 6,700 km canals and rivers of the French waterway network. In order to ensure effectiveness, since its creation in 1991 (taking over from the Office National de la Navigation) VNF focused on modernizing the infrastructures, and much like the countryside crossing keepers, lock attendants have gradually been replaced by automated facilities.

The structures managed by VNF mainly include locks and dams. The latter are often associated with hydropower microplants not managed by VNF. VNF is mainly in charge of controlling flood prevention and maintaining waterways for navigation, but also ensuring the best possible conditions for dryness, flow stability, protection of the environment and monuments, etc.

Automating a small sized lock is rather easy, but it is indispensable, considering the absence of humans, to ensure remote surveillance. For small, often remote, locks, the only economically acceptable solution to send remote information consists in using the public telephone network, whether wired (PSTN) or radio (GSM). With for each structure, one daily call (average) at the local fee, remote transmission costs remain perfectly affordable, from 15 to 30€ per month (the number of calls varies considerably according to the structure, but one average call per day is a perfectly acceptable value).

The remote information transmission function is most of the time ensured by a remote terminal unit (RTU) communicating with the programmable controller (PLC). The production cost of this installed, wired, and configured RTU ranges from 3,000 to 3,500 € ; to which the share in the central management station is added, about 500 € per station for TOPKAPI.
Therefore, the remote monitoring part (automation systems excluded which are indispensable today, even in the case of human presence) is an investment cost per site of about 4,000 €, with an annual operating cost of 300€.

Within the North-East regional district of VNF, TOPKAPI gradually imposed itself in many projects, meeting all the functional requirements of VNF, mainly for the following reasons:

	it is a genuine industrial supervisor capable of managing large-size structures connected locally with controllers.
	It is particularly well adapted to remote management applications, and is compatible with most RTUs manufacturers.
	It includes a top range graphic editor enabling to produce high quality screens and fluid navigation between screens.
	The TOPKAPI remote client station enables remote intervention within conditions virtually identical to local management.

TOPKAPI more particularly equips the FROUARD-CLEVANT remote control site near Nancy, which manages the dams in Blenod, Pont a Mousson, Liegeot, Pompey, and Frouard.
Because of the size of the structures concerned on this channeled section of the Moselle river (for heavy boats), a redundant version of TOPKAPI was chosen, with automatic processing failover between the main station and the backup station in case of failure.

During current operation, both redundant stations are used indifferently and simultaneously for operation. Operating by remote client station was used to enable a dam operator to remotely train and support colleagues with insufficient knowledge of the facilities. In addition to usual browsing, fault processing and remote control functions, TOPKAPI plays a key part in monitoring levels and flows. It detects mismatches between information transmitted by the various devices, calculates flows based on gauging, records level and flow curves. All this data is used to analyze the impact of various operations on the river, to act to stabilize the water ways and optimize the river's operation cycles.

On the small boating network, TOPKAPI also manages operating and pumping time metering for producing summaries and, if the equipment enables, traffic counting.

In addition to productivity gains it offers during operation, TOPKAPI is also a precious auxiliary to better apprehend and improve the behavior of the facilities.
This provides stricter monitoring of human activity and its impact (effect of excessive levels on farmland, cycle variations, minimum flow maintained, ...) while maintaining favorable operating conditions (navigation, microplants,...).

We thank Pascal ANCEL, technical adviser at the North-East Regional District of VNF, who provided most of the information used, and also Perax, manufacturer of RTUs, who broadly contributed to the introduction of TOPKAPI to the VNF.