# Help W/Battery



## Mechanical Alarm (Oct 18, 2010)

Hi Guys,

I just picked up a very cool watch that, I hope, just needs a battery. The case calls out a 312, which I believe is a hearing aid battery. I'm guessing that is the size. When I opened it, I found a 392/384 installed which lists as 7.9 x 3.6 (1.4 volt - not 1.55). Seems a little small for the case.

Can someone tell me the dimensions of a 312? I have looked on line and can not find them.

Does anyone know if the 392/384 is a suitable substitute for a 312, or am I all out of whack here??


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## Dusty (Feb 3, 2010)

321 renarta = sr616sw (maxell,panasonic,sony,toshiba)

v321 (varta)

321 (rayovac)

D321 (duracell)

611 (bulova)

280-73 (citizen)

hope this helps.


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## Mechanical Alarm (Oct 18, 2010)

Dusty said:


> 321 renarta = sr616sw (maxell,panasonic,sony,toshiba)
> 
> v321 (varta)
> 
> ...


NOT a 321 a... 312 - I was confused at 1st too.

Thanx for the quick reply Dusty... That is why I am interested in the dimensions as well.


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## Dusty (Feb 3, 2010)

arrrr sorry :blush2: dont have a 312 on my list


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## bridgeman (Dec 9, 2008)

check electric watches site on top banner her --batteries-doesnt seem to list a 312 but does have bateery sizes etc


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## harryblakes7 (Oct 1, 2010)

I think we need some info on the watch......... is it an Accutron??

Dimensions you state are correct for the 312 which is 1.4v

The 392 is a high drain battery and the 384 is a low drain battery, both at 1.55v

Me thinks what you really want is a 325 battery, 1.35v, unavailible as it's a Mercury one.....

Send Paul a message on his "electric-watches" website, i'm sure he will advise you on the best way to go, he is a top man!! :yes:


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## Mechanical Alarm (Oct 18, 2010)

harryblakes7 said:


> I think we need some info on the watch......... is it an Accutron??
> 
> Dimensions you state are correct for the 312 which is 1.4v
> 
> ...


Re-read my post - Sorry I may have confused the issue as well. The 312 is a 1.4 volt and I can't find the dimensions for it (Diameter & width). The installed battery that was shipped with the watch, is the 392/384 which lists a size of 7.9 x 3.6 (and 1.55 volts - like all watch batteries). This one seems a little small for the case. My research came up with it (the 312) being a hearing aid battery but I could not find the physical dimensions anywhere for the 312. I'll give it a little longer before contacting/bothering Paul. Does anyone know the compatibility of the 392/384 with the 312 and is the voltage difference a problem? I also saw the 392/384 called a "Multi-drain battery", probably able to use this or one of the others - 392 OR 384.

No it is not an Accutron... waiting for the battery till I give the big reveal... something quite different. Hopefully without giving it away, the battery cover states, "BATTERY" (curved around the outside edge of the cover) with a Minus sign under that (I'm assuming the polarity) and then the # "312" (again, assuming the size of the battery). Watch is from 1972. How bad is it to get the battery in up-side down? Can this cause any electrical problems? Afraid to try the polarity the other direction. It was shipped with "Negative" side 'up', facing the back - Positive to the dial side.

Thanx again.

Robert


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## watchnutz (Jan 18, 2008)

312 dimensions are Hgt 3.6mm dia 7.9mm


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## Mechanical Alarm (Oct 18, 2010)

watchnutz said:


> 312 dimensions are Hgt 3.6mm dia 7.9mm


Thanx for that Bill. So, looks like the dimensions are the same as the 392/384 battery(ies). Just seemed a little too small. Should I be concerned about the slightly less voltage? How about the polarity issues? Any thoughts..., anyone...?


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## Jack G (Apr 7, 2008)

Hello Robert and I hope all is OK with you.

As stated the 384 and 392 have the same physical size.

The 384 is for use in low drain watches ie. just a watch function analogue or digital.

The 392 is for high drain ie. watch plus an alarm or a light (some digital watches) or both.

A 392 should work fine in a watch designed for a 384 but battery life will be short the other way round.

Putting a battery in the wrong way round should not cause any damage - well it never has in my 13 years experience with battery watches.

Hope this helps, regards, Jack


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## Mechanical Alarm (Oct 18, 2010)

Jack G said:


> Hello Robert and I hope all is OK with you.
> 
> As stated the 384 and 392 have the same physical size.
> 
> ...


Hello Jack - great to hear from you!

Thanx for the info! And all this time I thought you only knew vintage Omega's. Oh wait... there was an LED time in there as well, huh?

Hope to talk with you soon!


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