[time-nuts] line frequency website
hmurray at megapathdsl.net
Fri Dec 30 20:07:32 EST 2011
> Well, I design systems that we send out all over the world. I have various
> spec numbers that indicate some rather optimistic tolerance. For example, I
> have measured actual outlets in the US at 70VAC and 142VAC, which is well
> outside the published tolerances. I get a lot of flack from management when
> I try to use those numbers as operational limits instead of the utility
> published ones. Some empirical evidence from a third party would help a lot.
70 and 142 seem more than a bit unreasonable. How long did they stay at that
I like Jim's suggestion of asking the guys who are collecting the data.
I've been using my UPS to monitor line voltage. It's got commands to read
the min/max input voltage since the last time you asked.
My software writes a line to the log file every 5 minutes or more often if
the line voltage changes by more than 2 V. It runs about 30K per day.
Mostly, things are boring: 120-125 V. Occasionally I see a glitch.
I should write some code to scan the old files and collect statistics.
These are my opinions, not necessarily my employer's. I hate spam.
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