Spallation Neutron Source high-power RF transmitter design for high availability, ease of installation and cost containment

The availability goals and installation schedule for the Spallation Neutron Source (SNS) have driven the availability and installation of the SNS linac´s high-power RF systems. This paper discusses how the high-power RF systems´ availability and installation goals have been addressed in the RF transmitter design and procurement. Design features that allow RF component failures to be quickly diagnosed and repaired are also presented. Special attention has been given to interlocks, PLC fault logging and real-time interfaces to the accelerator´s Experimental Physics and Industrial Control System (EPICS) archive system. The availability and cost motivations for the use of different RF transmitter designs in the normal-conducting and super-conducting sections of the linac are reviewed. Factory acceptance tests used to insure fully functional equipment and thereby reduce the time spent on installation and commissioning of the RF transmitters are discussed. Transmitter installation experience and klystron conditioning experience is used to show how these design features have helped and continue to help the SNS linac to meet its availability and schedule goals.