Change in retention Times after changin computer clock time
Posted: Tue Feb 21, 2023 5:30 pm
Has anyone experienced the following:
We have 2 older Agilent 1200 HPLCs, purchased last year at auction. They each have identical PCs running ChemStation software, Rev. B.04.03 [16]. They are "stand-alone" systems, so there is no communication between the systems and they are not connected to the internet or any network/routers, etc.
We run 2 completely different analytical methods, 1 on each system, for the analysis of completely different compounds, and the retention time is has been highly reproduceable (16.5 min. for compound A on LC-1, 17.7 min. for compound B on LC-2). We recently made a computer clock adjustment for each PC (time of day was off by 1 hour at purchase for each of them). After the adjustment, the retention time for each analyte was off by about 5 minutes, each system, and the ratio of the change (current vs. original RT) was about the same for each system, (ratio = 1.3).
As strange as this sounds, can a computer clock time-of-day change affect the way ChemStation calculates retention time? Decades ago I had a similar problem using British-made computers, whose internal clocks were set for 50 Hz British AC power (60 Hz of course in the US) (We are a laboratory operating in the USA).
Thanks for any insights about this weird problem.
We have 2 older Agilent 1200 HPLCs, purchased last year at auction. They each have identical PCs running ChemStation software, Rev. B.04.03 [16]. They are "stand-alone" systems, so there is no communication between the systems and they are not connected to the internet or any network/routers, etc.
We run 2 completely different analytical methods, 1 on each system, for the analysis of completely different compounds, and the retention time is has been highly reproduceable (16.5 min. for compound A on LC-1, 17.7 min. for compound B on LC-2). We recently made a computer clock adjustment for each PC (time of day was off by 1 hour at purchase for each of them). After the adjustment, the retention time for each analyte was off by about 5 minutes, each system, and the ratio of the change (current vs. original RT) was about the same for each system, (ratio = 1.3).
As strange as this sounds, can a computer clock time-of-day change affect the way ChemStation calculates retention time? Decades ago I had a similar problem using British-made computers, whose internal clocks were set for 50 Hz British AC power (60 Hz of course in the US) (We are a laboratory operating in the USA).
Thanks for any insights about this weird problem.