What does this mean? - Timeograph readouts explained

[steviecav]

Hello, just got my qc pics for the PAM359M and one of them shows the watch wired up to a machine that displays the watch performance. You have all seen it a hundreds times I am sure but can anyone explain to me what the readings mean? We have 'BEAT: AUTO 28800' - what is the 28800 referring to? Is it how many beats per hour? Is the higher the number the better the quality?

Then we have 'Lift Angle: 52.3 degrees' what is that all about?

'Rate: + 0.00s/d' is this seconds per day lost or gained?

'AMPLITUDE: 305 degrees' does this refer to sound of the movement?

'BEAT ERROR: 0.7ms' ?

This is all still new to me and I am enjoying learning about these things so any information would be appreciated. I have attached a picture.

 

[chromed.]

beats means e "speed" of e mvmt..
lift angle means e angle e watch is at.. ( but i may b wrong )
rate means +/- amount of sec it gains or loses per day..or means how e watch is keeping time..

i'm unsure about e rest.. but i personally look out for e beat & rate..

cheers.

btw, post e rest of ur QC pics, mate!!

 

[smascarinas]

Hey Mods sticky this if we ever get a QC page dedication. I would love to know as well.

 

[steviecav]

Rest of QC pics as requested.

 

[trailboss99]

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.




Col.

 

[steviecav]

trailboss99 you are a star. Thank you very much for putting me right. Although now I am a little miffed that my amplitude is over 300 degrees. But I have a low beat error so what the hell.

 

[trailboss99]

Mate, for our MVTs 305 is oke. Anything under 315 is acceptable for a Chinese MVT. Who is the dealer BTW?

 

[steviecav]

Puretime

 

[smascarinas]

Good info! You should change the title to QC PICS TEST RESULTS EXPLAINED... and sticky it!!!

 

[GreenHornet]

Gentlemen,

I'm looking to get my first PAM and I like the looks of this watch. I would appreciate any feedback on the OP's QC pics (as I'm sure he does as well). What are some of the things to look for first?

I'm still very much reading and learning and I respect the wealth of knowledge on this board.


Sent from GreenHornet's iPad 2 using Tapatalk

 

[geo1nah2a]

The QC of the caliber look really promising!

Allow me to say that some of these measurements might be off by the time it lands in your hands: Traveling via courier can alter the regulation or create problems with the hairspring. Not much the dealers can do about the misbehavior of the delivery people!

[ame="http://www.youtube.com/watch?v=4V64r3q4FuA"]YouTube - Ace Ventura: Pet Detective "HDS Delivery Man"[/ame]

 

[justlounging]

Does the Amplitude vary for different movements? I noticed that on the QC pics from other members on their PAMs with 6497, the amps are around 220-260 degrees..

how does one mod/regulate the watch so that the amp will rotate at an ideal degree?

Thanks in advance for explaining this..

 

[trailboss99]

Yes, amplitude varies from movement to movement. You may have noted in my explanation that the 6497 has a very small lift angle of 44deg, as a result the amplitude will be less. You can't play with these things unless you have a timeograph guys, it's something you need to live with. If the watch is keeping good time it's nothing to worry about anyway.

 

[RobbDizzle]

What would an acceptable amplitude for an A21J be?

 

[cybee]

Heck I never worry about beats, amplitude, lift and launch angles. If my asian beater reps don't lose or gain more than 1 or 2 minute a day I'm happy.

 

[tommy_boy]

Launch angle issues are a concern for me, actually.

We have mountains up here and I don't want to slam into one, thanks to my watch.

I suppose if the watch was accurate, the rescue guys would know when I bit the dust. Or snow.

 

[cybee]

Launch angle issues are a concern for me, actually.

We have mountains up here and I don't want to slam into one, thanks to my watch.

I suppose if the watch was accurate, the rescue guys would know when I bit the dust. Or snow.

In your case TB I would definitely worry about launch angles : )

 

[trailboss99]

From memory anywhere between 280 and 315 deg should be fine for a 21j, a little less is no reason for alarm however. As I said, if it keeps time all is well.

BTW, just to clarify, the beat rate and lift angle shown on the timer are SETTINGS, not readings. The correct beat rate is set (or detected by the device in auto mode) along with the correct lift angle in order to get the other parameters. Therefore, the beat rate (VPH) readout is not telling you that the rate is exactly 28,800, that is what it is set to, same with the lift angle. If the lift angle is not correctly set as an input a false beat error and amplitude will be generated. I am not sure of the correct lift for an a7750, I am endeavouring to find out.

 

[RobbDizzle]

Thanks for the info tb...it means a lot to finally understand how to read these things even if only 1 or 2 of the readings are immediately pertinent to the everyday buyer.

 

[justlounging]

Yup..thanks T-boss for the explanation..

Back to my earlier question, assuming one has the correct equipment to test the movement and that the correct beat rate n lift angle are used, how is the amplitude adjusted?

If i recall correctly, Regulation of most movts are usually done by the arms near the balance spring..and minimal loss/gain is achieved thru trial and error..

Correct me if i'm wrong..

Thanks!