Technical question: is it possible that (lack of) power can impact the

So, after a few days of wearing my new QdI, I’ve gone back with my good ol’ 47212.

Whilst I was wearing the QdI, every other day I would wound up my 47212, to ensure that it kept the day and date current. I did forget once to wind it, and when I picked up the watch this morning, the watch had run out of power, and the time was stopped at about 1am. The day had been changed to Wednesday, but the date was still stuck on the 27th.

In fact, I have had this problem a few times over the last few years, when I would look at my watch and realise that the date wasn’t keeping up with the days... And I had the watch sent to VC to get checked. This is the first time that it has happened since she’s been back from the spa.
So anyway, my question is this one: because it is all gears, shouldn’t the date change automatically, or could it be that, if at the time the date change is to occur, if there is not enough power in the power reserve the mechanism will not be activated?
Thanks for your help
other than instantenious perpetual calendars where all
09/28/2011 - 13:43
calendar functions jump at the same time at midnights, in the majority of QP's including yours the different indications jump at different moments (anywhere between midnight or 3AM depending on the watch) as not to have an adverse effect on the amplitude. So it could be that in your watch the day jumps sooner than the date.
Thanks for the answer
09/28/2011 - 13:59
Seems  a logical explanation... I'll check to see at what time the date usually changes Thanks Alex Francois
I've found some models...
09/28/2011 - 18:41
take four hours to gradually change the date!  As Alex said, this was intended to draw as little power as possible so that timekeeping wasn't affected.
Re: I've found some models...
09/28/2011 - 21:00
All my perpetuals, VC, Ulysse Nardin, Urban jurgensen, and Lange all change the date more slowly than the day. I believe its a power coservation issue. JB
Re: Re: I've found some models...
10/04/2011 - 03:53
My AP EOT changes the indications over some time period, but (at least on most days :-)) my Vianney Halter Antiqua snaps both the day and date sharply over right at midnight.  Quite a show!  Of course many other calendar watches have an instantaneous date change -- my VC OS chrono among them.  I have to say that I'm a fan of instantaneous jumping -- whether it's chrono minutes (Lange Dato) or dates.  One of my complaints about the Dato is that the date creeps from one day to the other -- yeah, it's probably better for timekeeping and movement part longevity, but not aesthetically pleasing to me! Best, Gary
Thanks Gary, Dean and JB
10/04/2011 - 13:16

consistent feedback, I'm sleeping better now knowing nothing is wrong with my 47212smiley