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Automatic Watch Power Reserve Chart Help


Titanium

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I have been playing with some automatic watches recently so I got a Bergeon 7803-230 automatic watch tester. You put the watch completely run down on the watch holders and it spins them at 4RPM. You leave the watch on it for a known period of time e.g. 3 hours. Let the watches run down. Note the hour it stopped at. From this you know the power reserve and you can compare this on the chart.

My interpretation of the chart is the left had column is how long the watches are spun for and the right hand column is the power reserve in hours. So if you spin the watch for three hours it should run for between 14 to 24 hours. This seems a lot of wind from 3hours of spin.

Plus I thought automatic watches needed wound by hand when they run down to get them going again.

Any help would be appreciated.

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Yes and even more with bidirectional auto mechanisms - right side of right chart.

For example a Seiko 7S26 fully winds in 1 hour on a 30 rpm winder. And it start fine from being fully unwound without having any mean to be hand wound.

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I have a Chinese version of the Bergeon which also has this chart. To be honest I have never bothered to work out what the chart indicates. I just use the winder to check that the auto is functioning correctly over a period of say 48 hours & also to give a better indication of how a watch is performing.

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On 04/02/2017 at 9:00 AM, clockboy said:

I just use the winder to check that the auto is functioning correctly over a period of say 48 hours & also to give a better indication of how a watch is performing.

That's a really good idea. Thank you to everyone for the help.

 

I know the tester is supposed to be in a vertical position to the watches are rotation in three axis's instead of one however does it make much difference?

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