Timepieces:Education & Repair
Selecting New Batteries
Accomplish this task efficiently to cut repair time and convey high
By David Christianson
Certified Master Watchmaker
President, American Watchmakers-Clockmakers Institute
Something that seems as simple as changing a watch battery can be surprisingly
complex when it comes to selecting a correct replacement cell.
Batteries are selected by their size (diameter and thickness), chemical
makeup and the speed at which their power drains (simply called "drain").
Fifteen distinctly different numbering systems are used today, as developed
by cell manufacturers and watch manufacturers.
No matter which system you use to organize your battery stock, you'll
need to be able to cross-reference to the other systems; at some point they'll
all come across your showcase.
Four Major Groups
To simplify the systems, I group them into four major ones:
- USA: Three-digit numbers, commonly 301 to 399, developed by Eveready
Co. and used primarily by Swiss and U.S. manufacturers. They simply represent
a stock number.
- Japan: Alphanumeric figures from Japan used mostly by Asian manufacturers.
The letters indicate the chemical makeup of the battery, the shape, the
"drain" and usage. The numbers show the cell's diameter and thickness.
- Manufacturer: These may be the same as the USA or Japan systems, or
they may be unique to that particular cell manufacturer.
- AWI: Alphanumeric figures with one letter followed by two digits. This
system was developed two decades ago by Ewell Hartman, a certified master
watchmaker and fellow of the American Watchmakers-Clockmakers Institute.
It provides common denominators indicating chemical type and drain; it
also provides a reference system for all batteries currently made and includes
dimensions so if the battery is missing, you can begin your search by measuring
the diameter and depth of the battery well.
While some stores have organized their batteries using one of the first
three systems, many have reorganized their repair area using the AWI system.
As president of this organization, I lean strongly toward using its system.
But more importantly, I recommend the system as a retail jeweler who finds
it simpler, more efficient and better able to meet the needs of the full
universe of watch battery replacement requests.
Thousands of retailers have adopted the AWI Battery Book.(The
reference book was updated this past fall and is available from AWI for
$5 by calling 513-367-9800. Many major battery suppliers also sell the book.)
The book cross-references all the systems. To use it, you'll need a set
of labels (which you can buy for $3.50 or make yourself), one for each drawer
in your battery supply cabinet.
Into the appropriate drawer you place all batteries, from any manufacturer,
that can be used for the specific replacement. Whether you prefer Maxell,
Eveready, Renata or even a mixed assortment, the guide lists the correct
drawer number for every battery that meets its specifications. Briefly,
the AWI system uses these abbreviations:
|| 1.5 volts |
|| 2 or 3 volts |
|| 1.3 volts |
|| 1.55 volts |
|| Silver Dioxide
|| 1.55 volts |
|Even Numbers: Low Drain. Recommended for watches that have no light, alarm
or LED display.|
| Odd Numbers: High Drain. Essential for watches that have a light,
alarm or LED display.|
Next month, we'll provide real-life situations to illustrate how to use
the AWI battery book to locate the correct cell quickly.
David A. Christianson is a fourth-generation owner of Christianson
Jewelry, Kendallville, IN. Besides serving as president of the American
Watchmakers-Clockmakers Institute, he is a certified master watchmaker and
a fellow of the British Horological Society. He discusses watch repair for
the sales staff in this column each month. Send questions, suggestions and
comments toProfessional Jeweler,1500 Walnut St., Suite 1200,
Philadelphia, PA 19102; firstname.lastname@example.org.
Copyright © 1999 by Bond Communications.