NA62 - GTK Procedure to switch ON/OFF the Cooling Plant version 0 Introduction This procedure is rather a preparation of the Stations for the switching ON/OFF, while the actual power ON/OFF is done by EN-CV personnel. The Cooling Plant operates on three Stations, thus the procedure to prepare the switching ON/OFF of the Plant has to be repeated three times, once for each Station. The sketch of a Station is the following: Vi Detector Vb Vo By-pass

1) Preparation to switch ON the Cooling Plant Close Vi (*) Open Vo Open Vb After this operation, the Detector is in a safety state and the liquid would go through the by-pass 2) Switch ON the Cooling Plant Whenever the Cooling Plant is stable (one minute or so) with pressure and flow at the nominal values, one can switch from by-pass to Detector by doing the followings: Open Vo Open Vi Close Vb (*) Open(ON)/Close(OFF): handle position

3) Switch OFF the Cooling Plant The switch off of the Cooling Plant should not do any arm to the Detector. The good practice would be, before switching off: Close Vi Open Vo Open Vb Leaving the system ready to be switched ON again (see 1).