Power Supply Room

The power supply room may not seem to be an important part of the design, but that is not entirely true.  Especially during machine startup, seeing that the power supplies are responding to commands can save time.  Also, during maintenance, the designers had experience that showed machine control within the power supply room can help to debug issues and watch things like target loading, RF matching between the final tetrode and the machine, and monitoring of the high vacuum. 

The design of the vault has taken into account that it is desired to add a short beam line off of the cyclotron in the future for solid target isotope production.  The vault is rectangular to accommodate an approximate 1-meter long beam line.  Space for two large hot cells outside of the vault and adjacent to the plug door and a short pneumatic (“rabbit”) target transport system has been foreseen with appropriate trenches and conduits.  The beamline, associated quadrupoles, deflectors, and vacuum pumps has its own associated 19” rack of electronics.  The space directly to the right of the last rack (containing the main coil and ion-source supplies) has been reserved for the future rack of equipment and electronics.

One issue that the designers faced was that every 25’ (7.6 meters) there was a vertical I-beam that supports the upper floors of the building.  Fitting the power supply room, the cyclotron vault, the plug door, and some staging space outside the vault required that the vault be placed between the staging area and the power supply room.  This provided for multiple penetrations of the vault from both sides and there were ten (10) 4” or 100 cm diameter conduits that lead from the power supply room into the cyclotron vault.  All penetrations have two 90˚ bends or are set into the concrete at compound angles so as to prevent the escape of neutrons from the vault. 

As can be seen in the picture to the left (above), an operator station has been placed behind the electronics cabinets.  This allows for the operator to watch the target syringe drivers to load (they are not visible in the photograph but they are in the back corner next to the desk).  The large black cabinet is a fan coil unit to control the temperature and humidity.  On the right (above) can be seen a waterless fire suppression system placed on the wall.  Because the facility is within a clinical hospital building, sprinklers are required by local code.  In order to protect the electronics, which, are worth over $300,000, a pre-action fire suppression system (Fike) has been installed.  Also, of note, the capillaries in the sprinkler heads have been changed to a higher temperature.  The pre-action system is designed to trigger at ≈ 135˚F (≈ 57˚C) while the water sprinkler system will trigger at ≈ 235˚F (≈ 113˚C).  Normal sprinkler systems trigger at the lower temperature.