VAX 11/750 power supply fault

Hi I am not familiar with these machine either. Still, I suspect that he may be looking at a broble of feedback. Many high power outputs use remote sensing to supply the correct voltage at the load, not at the powersupply. He states that he doesn't have anything connected. One would still use common sense. Don't connect real components until one knows things are working correctly. Put dummy loads on the supplies and make sure that any remote sensing is properly connect at the loads. The loads don't have to be full current loads in many cases. I've found that various auto lamps are enough to get a feel for correct operation. For low current, dash lamps and for high current, head lamps. Don't expect these lamps to light with 2.5 volts on them, they are just someplace to sink current. Lamps are almost constant current devices, over small ranges of voltage. Dwight _________________________________________________________________ Connect and share in new ways with Windows Live. http://www.windowslive.com/connect.html?ocid=TXT_TAGLM_Wave2_newways_112007