Watch test meter readings

[pfcdre 0]

Hi all,does anyone know what amplitude and lift angle refer to,and what is considered a good result, I have no idea and am keen to learn,knowledge is power, lol,thanks

[Greenhat 0]

Hi all,does anyone know what amplitude and lift angle refer to,and what is considered a good result, I have no idea and am keen to learn,knowledge is power, lol,thanks

http://watch-pop.com/omega_3/watch-23913.html

[trailboss99 997]

Re-post from next door:

 

Oke, let's address these one by one.

 

We have 'BEAT: AUTO 28800' - what is the 28800 referring to? Is it how many beats per hour? Yes, it is beats per hour. In this case (28,800) it equates to 8 ticks per second. Common beat rates are:

 

5 beats per second....= 18,000 bph = 2.5 hz

5.5 beats per second = 19,800 bph = 2.75 hz

6 beats per second....= 21,600 bph = 3 hz

7 beats per second....= 25,200 bph = 3.5 hz

8 beats per second....= 28,800 bph = 4 hz

10 beats per second..= 36,000 bph = 5 hz

 

Then we have 'Lift Angle: 52.3 degrees' what is that all about? Lift angle is the angle of rotation of the balance in which the roller pin is in contact with the pallet forks.Lift Angle is used to along with the rate to calculate Amplitude. It is not measured by the machine, it is set before testing to the correct value for the watch. This is usually between 50 and 52 deg for common MVT types but much higher for a co-axial escarpment like in a gen Omega. A Unitas 6497 however is only 44deg. If this is not set correctly all measurements will be off. I am not sure of the correct beat angle for an a7750 MVT but no doubt a little research on the gen fora would find it. If not, an email to Shanghai Watch (in SIMPLE english) requesting the correct lift angle, and amplitude for the 3L chronograph would get an answer.

 

'Rate: + 0.00s/d' is this seconds per day lost or gained? Roughly speaking, yes. It is not a real world measurement tho as it varies depending on the position of the watch which is why COSC MVTs are tested in 5 or more positions.

'AMPLITUDE: 305 degrees' does this refer to sound of the movement? No. Amplitude is the number of degrees thru which the balance wheel rotates, usually around 260 to 315deg. anything above 315 is getting a bit on the high side and may cause issues. 305 is fine, 280 to 300 is more or less perfect.

'BEAT ERROR: 0.7ms' ? The difference (in milliseconds) in the length of beats. The lower the better, anything below 1.2ms is fine in these MVTs, below .9 is desirable, 0 is perfect with the COSC testing requiring below .5 in all positions.

 

Hope that clears that one up.

[Cynikal.Mindset 1]

okay, what about the graphed line on the timegrapher? I've seen pretty flat ones, ones sloping downwards and ones sloping upwards. Whats the deal?

[Scavolas 0]

What a great post, trailboss99!

I would say this might be a sticky, if it wasn't 'just' a reply...