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While searching for an information on the C07.111, I stumbled upon this article from the AWCI website with interesting information on the battery (mainspring/barrel parameters) http://www.awci.com/wp-content/uploads/2013/10/TomsTips_Web_Nov13.pdf for ETA Calibres.

While it didn't include the information I was searching for, it is interesting from a theoretical point. The table lists theoretical reserves and I notice that the 2824-2 has 45.1 hours, much more than the 38 advertised. While 38 has to be a conservative number; I'm amazed at the amount of derating they use.
 

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That's a very nice find, thank you.
Though as a non-watchmaker, I find it odd to refer to a spring as a battery.
I assume the derivation of battery is comparable to that of pile - a collection of potential-generating cells.
I don't think that accurately describes a spring.
Anyway, my sole 28xx-powered watch as a 41 hour PR, I can't imagine getting 45 hours on a full wind (not a charge :) ).
 

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You can blame Roland Ranfft. He describes it as "mainspring / battery" on each of his movement description pages. I view the mainspring as the long skinny part that pops out if you are not careful. I consider the battery everything from the ratchet wheel to the teeth surrounding the barrel (including their interaction with the next gear over).

There was a day when this made complete sense.
 

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Ahhh, maybe a translational issue. Anyway, your main point is what matters, 45 hours on a 2824, wow.
Most of my watches have PRs that are about 10% more than advertised.
 

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OK, I just got straightened out by the big kids over on another thread. It is "Mainspring" or "Barrel Assembly". Batteries are what we always though they were, even before the invention of quartz.
 

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While searching for an information on the C07.111, I stumbled upon this article from the AWCI website with interesting information on the battery (mainspring/barrel parameters) http://www.awci.com/wp-content/uploads/2013/10/TomsTips_Web_Nov13.pdf for ETA Calibres.

While it didn't include the information I was searching for, it is interesting from a theoretical point. The table lists theoretical reserves and I notice that the 2824-2 has 45.1 hours, much more than the 38 advertised. While 38 has to be a conservative number; I'm amazed at the amount of derating they use.
The theoretical run time is just that - theoretical. It is taken as a system with no loads or frictional losses, which clearly is not reality. As you know, a watch will stop when the loads inside it are greater than the torque being supplied by the mainspring, so by it's very nature this is variable. Often people new to working on watches have t be reminded that they need to let the mainspring down before removing a lot of parts, because there is always wind left on a spring.

Why ETA uses 38 hours is a puzzle for me, because if I freshly serviced one and only got 38 hours from it, I would be tearing it apart again to find the problem. But given that many brands buy these off the shelf, the movements have sat for a long time, they get stuck in a watch with no interventions, you sort of understand why they derate them a fair bit from what they are actually capable of. But 38 is probably one of the most extreme examples I can think of off the top of my head.

Generally speaking any movement that I have ever worked on has exceeded it's rated power reserve after service, so these numbers clearly indicate a less than ideal scenario.

Cheers, Al
 

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OK, I just got straightened out by the big kids over on another thread. It is "Mainspring" or "Barrel Assembly". Batteries are what we always though they were, even before the invention of quartz.
Here’s why I commented, not trying to be whiney :) :

 

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^^^ I took another look at the entire thread you quoted and see where you would be interested. I do remember the thread but didn't participate due to the fur flying. Why the fur, I have no idea (but I've been known to fly off the handle when properly stimulated).

My confusion came from a single source. Dr. Ranfft who participates on the Watchmaking board has spent many years putting together a database of movement information and for every movement he has a table that includes the entry "Mainspring / Battery". Somehow I got the idea that the two were synonymous and part of my confusion was that I'd never actually looked up a Quartz movement on his database, so all I ever saw was mainspring characteristics. I also thought I had heard someone else making the reference in a printed source but looking through all my books, nothing.

On the Watchmaking forum I used the reference and promptly got laughed off the forum. I eventually recognized my mistake and corrected it there and here.

To answer your question on the other thread, I would say wound, but I do remember something about Equipment/Maintenance Safety (and yes, I took an upper division college course on it) about springs being energized.
 

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^^^ I took another look at the entire thread you quoted and see where you would be interested. I do remember the thread but didn't participate due to the fur flying. Why the fur, I have no idea (but I've been known to fly off the handle when properly stimulated).

My confusion came from a single source. Dr. Ranfft who participates on the Watchmaking board has spent many years putting together a database of movement information and for every movement he has a table that includes the entry "Mainspring / Battery". Somehow I got the idea that the two were synonymous and part of my confusion was that I'd never actually looked up a Quartz movement on his database, so all I ever saw was mainspring characteristics. I also thought I had heard someone else making the reference in a printed source but looking through all my books, nothing.

On the Watchmaking forum I used the reference and promptly got laughed off the forum. I eventually recognized my mistake and corrected it there and here.

To answer your question on the other thread, I would say wound, but I do remember something about Equipment/Maintenance Safety (and yes, I took an upper division college course on it) about springs being energized.
Hi ExpiredWatchdog, thanks for looking through that thread. Things did get pretty heated and more than a few times I was told to get a life, hahaha (those with lives don't spend too much time on WUS).
I recall the poll came out strongly in favor of "winding" being the preferred term.
Someone might even have pointed out there that the term "energized" can be used for springs, as you just mentioned.
 

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I don't know if this is relevant at this point, but I also have an ETA 2824-2 in a Squale-Matic 60 Atmos. It reliably holds 42 hours of reserve, which is Squale's advertised spec. Is ETA using some kind of average which includes a diminishing PR over the movement's life-cycle, or is that 38 hours supposed to be the expectation for a fresh unit, at day one?
 

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I don't know if this is relevant at this point, but I also have an ETA 2824-2 in a Squale-Matic 60 Atmos. It reliably holds 42 hours of reserve, which is Squale's advertised spec. Is ETA using some kind of average which includes a diminishing PR over the movement's life-cycle, or is that 38 hours supposed to be the expectation for a fresh unit, at day one?
I regard it as a guaranteed minimum. All my watches have PRs around 10% beyond what is specified.

I think Archer’s answer in post #6 really says it all.
 
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