I'm sure you have good reasons for needing this scheme, but don't your products have model numbers? Wouldn't the serial number be redundant? What will you do if the serial number suggests one model and the model number suggests another model? What will you do if your company suddenly becomes popular and you outstrip your serial number capability? What will you do if you are bought by another company (two databases?) or if you purchase another company? Some companies that put too much information in the serial number find they have to simplify it because they have too many errors with people sending in warranty cards, reading them over the phone, etc. Same with using letters, or worse both letters and numbers. I'm of the camp that a serial number is simply a string of numbers, incremented for each product out the door, and leave all the other information in the model number. You can store a database that matches model numbers with serial numbers if you want a little redundancy, but anything more just means more trouble down the road. But then, I'm a big fan of database normalization, and this isn't exactly the same thing, so I may be approaching the problem from the wrong angle. So, in that vein, your requirements are: * Date of manufacture (To the week within a decade - 52 weeks, 10 years, 520 possible) * Model (How many models? I'll assume less than 100,000 models) * Serial (10,000 per year) * Human readale (implied - you probably don't want to have to run to a computer to figure out if the warranty is valid) * Easy, convenient Serial Number: AAx-xBBx-xCC AA, BB, CC are letters xxxx are numbers. dashes are dashes - spacing to group the numbers for readability. AA denotes the date of manufacture. The first letter is the 1/2 year - so A would be the first half of 2008, B would be the second half. The second letter is the week within that half year. xxxx is the plain serial number. Increment for every product, reset every year. BBCC is the model number. I have it split up so the product line is BB and the model is CC, but I don't know your product line and model permutations, so you may have to adjust it. The dashes show where you need to space your serial number. People deal with groups of letters/numbers much more readily than one long string. An advantage to this scheme is that the numbers and letters have specific spots, so one can readily recognize it as a serial number (in your company) and correct simple issues (such as O and 0, 1 and l, etc). You're only using capital letters, so some errors are avoided as well. Will still have issues with M and N, and B and D over the phone, but you can eliminate those or use the four digit serial in the middle and the first letter (year) to find the right one. This is a very redundant serial number, so it's long, but it's essentially what you're asking for. Any scheme will work, though. Hope this helps. -Adam On 6/24/08, Mohit Mahajan (Lists) wrote: > Hello, > > We manufacture a lot of different kinds of instruments (but each in > small quantities). Our serial numbering scheme so far is pretty basic: > ABCD-EFGH. AB tells us the week and CD the last two digits of the year. > EFGH starts at 0000 every year in January, and increases count with each > instrument manufactured. It gives no indication which model or what was > manufactured. This info would be given by a spreadsheet where the > description of the instrument is entered next to the serial number. So > we'd have to look up the serial number in this sheet to know what > instrument we're talking about. > > I'd like suggestions for a serial number scheme that could indicate the > instrument model/type, date of manufacture (for warranty purposes). And > it shouldn't be too long, about 8-10 characters. > > It would be great to know what schemes members here or their companies > use to number their products. > > Thanks, > Mohit Mahajan. > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- EARTH DAY 2008 Tuesday April 22 Save Money * Save Oil * Save Lives * Save the Planet http://www.driveslowly.org -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist