SNCF TGV Iris 320

Iris 320 is a modified TGV train operated by SNCF International as a dedicated Track [geometry car|track recording train] for high-speed railways. The train can run at and consists of two power cars and eight trailer coaches, providing a long laboratory. It was converted from former SNCF [TGV Réseau] passenger train number 4530.
The train is primarily used for monitoring the whole of the French high-speed LGV network every 15 days. In addition it surveys other main lines in France operating at above and the HSL 1 high-speed line in Belgium for Infrabel.
Once every two months, Iris 320 takes a survey of the Channel Tunnel for Eurotunnel and of High [Speed 1] for Network Rail in the United Kingdom. The cross-channel trips are diesel-hauled by Eurotunnel Class 0001 locomotives and travel at.