Ten Years Operational Experience with the ISR Power Supplies

Performance and reliability improvements have been made to the 300 magnet power supplies, their remote control system and the mains distribution network. With the high beam currents now stacked in the ISR, physics data taking would be degraded if the power supplies only performed to their original specifications. It has been necessary to improve the low frequency noise generated by the power supplies at least two orders of magnitude. Modifications have improved the reliability of the power supplies to the state that it is now rare for a beam to be lost due to a power supply failure. Overall, the results have given longer and cleaner stable beam conditions for the physics programme, improved flexibility of operation and easier maintenance.