From silviu@krl.caltech.edu Thu Oct 26 14:31:53 2000 Date: Thu, 26 Oct 2000 11:37:20 -0700 (PDT) From: Silviu Covrig To: Jeff Martin Subject: Cryopump (fwd) Hi Jeff, Can you put this on the local web site in the appropriate place, Thanks, Silviu Hi Bob, The cryopump's motor test is over. We acumulated a whole 217h of continuous running (9 days and 1 hour) time at 30Hz/60V. The whole time the motor maintained a running frequency of 30.0()Hz at an average current of 160mA, 9.6W of power consumption at LN2 temperature (77.35K). The filling He gas was at about 20psi (1atm + 5psi), and the density of the gas in these conditions is about .64kg/m^3 or .64*10^-3g/cm^3 about 100 times less than LH2's density. The whole running time budget is: 10/10 to 10/12 45h of continuous running 10/13 to 10/13 8h of continuous running-- 10/14 to 10/14 15h of continuous running---- 33h here 10/15 to 10/15 10h of continuous running-- 10/15 to 10/24 217h of continuous running Hopefully this speaks a bit about reliability of the motor, Silviu cc: Kenneth --------------------------------------------------------------------- Silviu D. Covrig Kellogg Radiation Lab 106-38 Caltech, Pasadena, CA 91125 Work phone: 626-395-4327