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Why your mains powered clock is running 6 minutes slow

I just read the whole thread twice, and I don't understand a single word.
 
This is because some users apparently got into very political discussions and some comments were deleted. Thus the disjointed remaining comments..

Yup politics is no bueno here. Aka keep opinions to ones' self about them lol.
 
I just read the whole thread twice, and I don't understand a single word.

You need to first understand that every watch needs an oscilator to keep pace (accurate time). Mechanical watches use swinging balance wheel, modern quartz watches use quartz crystal which under specific current starts to oscilate at very accurate pace and there are mains clocks that don't have either, instead they use the oscilation of the mains power to keep time. Mains power oscilates at specific rate, 50Hz for Europe, 60Hz for US. If this rate is the same, you effectively have an externally delivered oscilator. Problem is, if oscilator is not keeping its pace, the clock will become more and more inaccurate as time passes. In case of mains, it was not 50Hz anymore due to high load, instead it was running at 49,98Hz. It may not sound like much, but it's less than 50Hz which means over time, clock will lose time and started lagging behind actual time. If mains was running above 50Hz, the clocks would be faster, running ahead of actual time.

Understandable enough?
 
My main's clock is keeping time perfectly well, thanks.
 
meh...

Not too many clocks are powered by an AC synchronous electric motor these days (chart recorders are though).

Ready to lock this thread up if it devolves into a geopolitical discussion
Yeah, when I read this news I actually looked around my house only to find none of my clocks have been running late...
 
This is because some users apparently got into very political discussions and some comments were deleted. Thus the disjointed remaining comments..
No posts have been deleted.
 
@Tatty_One Could you please unlock my OP as I need to edit it. I've already clicked Report a while back, but my request wasn't actioned.
 
@Tatty_One Could you please unlock my OP as I need to edit it. I've already clicked Report a while back, but my request wasn't actioned.
Just drinking my coffee at work, enjoying the peace for the first time in a while..... don't spoil it!
 
I remember years ago a company I started working for had an old Employee punch-in time clock at the main employee door that I would have to fix the time every month.. because whenever they ran the facility on their main generator (think hospital Generator size) the clock would run less than 60hz which would in turn cause the time to be off over time. Once I figured out the issue was caused by the generator I put a UPS on it. :laugh:
 
Thanks T, I've added a second link to this story in my OP now. :)
 
6 seconds ahead (time.windows.com direct)
0.1 seconds ahead (server via time.windows.com)
0.6 seconds ahead (server via time.nist.gov)
0.3 seconds ahead (server)
0.5 seconds ahead (server)

Okay, I give up.
 
I guess they all tend to average to the correct time, lol.
 
6 seconds ahead (time.windows.com direct)
0.1 seconds ahead (server via time.windows.com)
0.6 seconds ahead (server via time.nist.gov)
0.3 seconds ahead (server)
0.5 seconds ahead (server)

Okay, I give up.
Time keeps on slipping, slipping, slipping, into the future


Sorry, had to do it :p:laugh:

I remember years ago a company I started working for had an old Employee punch-in time clock at the main employee door that I would have to fix the time every month.. because whenever they ran the facility on their main generator (think hospital Generator size) the clock would run less than 60hz which would in turn cause the time to be off over time. Once I figured out the issue was caused by the generator I put a UPS on it. :laugh:
Generators have caused all kinds of problems with chart recorders at my job sites because of this. Thankfully PLC's and other controllers aren't usually affected by this too much.
 
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