Installation and 1rst priming of the Millau DN VLH

The Millau VLH has been commissioned on March 19, 2007 (see Newsletter n°6). It has been operating since then without significant incidents. Its production in the first 6 months has been higher than expectations due to its good performances and to a favorable pluviometry.

The Troussy VLH as seen from upstream

Once connected to the network, the 1rst VLH has been submitted to exhaustive commissioning tests. It is a DN 4500 (runner diameter 4.5 m).

The results have demonstrated a perfect homothety with the tests on a small-scale model. The overspeed at full gate opening (75 cpm) and the maximum overspeed (90 cpm) have been precisely as expected. The 410-kW maximum nominal power at grid level has been reached at the expected nominal speed of 37 cpm .

Since it has been commissioned, the Millau VLH has achieved productions in perfect correlation with the results of the models and the flows measured on the Pont le Rouge station on the river Tarn in Millau.

All along the tests and since then, the VLH has had a very smooth, vibration-free and silent operation. One must touch the machine to find out whether it is operating. Once connected to the network, the 1rst VLH has been submitted to exhaustive commissioning tests. It is a DN 4500 (runner diameter 4.5 m).