Resulting pressure reduction at nearest BT gauge is as expected, i.e. reduced by a factor of ~2.5.   

Also, there is now a large error in pump current converted pressure at the ion pump controller vs. independent gauge voltage -> gauge voltage converts to 2e-9 torr, ion pump controller indicates 1e-10 torr (converting 3 uAmps) -> 20 hour pump down curve of captured gauge data prior to opening valve is as expected -> ignoring pump current converted pressures at these small values