Kiwamu, Nutsinee, Jim, Dave

At noon we power cycled the h1oaf0 IO Chassis to hard reset the 16bit DAC card. We were suprised that both TCS chillers stopped running. During last week's IOP dac-disable events (which zeroed the DAC drives), the chillers kept on running for about an hour before tripping. As a further test, at 14:00 PDT we again powered down h1oaf0 CPU followed by its IO Chassis. At this point the chillers were operational. We then power cycled the AI chassis, which tripped the chillers. We then powered up the IO Chassis and computer, at which point the chillers tripped again. We were unsure if the trip was at the time the IOP model started, or h1tcscs model started driving the DAC channels.

Take home message: before restarting h1oaf0 IOP, CPU, IO Chassis or DAC-AI unit please contact Nutsinee.