  Reliable and reproducible performance of the more than 800 Relativistic Heavy
Ion Collider (RHIC) magnet power supplies is essential to successful RHIC
operation. In order to support power supply commissioning, a system was
developed to capture detailed power supply measurements from all the RHIC ring
power supplies during acceleration ramps. Diagnostic tools were developed to
allow experts to assess ramp reproducibility and rapidly identify problems. The
system has now become a routine part of RHIC operations, with data captured for
every acceleration ramp. This paper describes the RHIC power supply ramp
diagnostic system and considers its impact on RHIC operations.
