Parts Numbering Scheme
Roger Lascelles
numbering scheme.
The parts numbers need to go into our accounting system and on parts lists,
build lists and some schematics, so we don't want them to be too long.
Letters and digits are OK, but each must start with a letter. Sort order is
a consideration, because computers sort strings from left to right, often in
ascii or similar order. That means each character position has significance
and it might be best if every part had the same number of characters.
The storeroom must be organised by part number, so that we can work
systematically to find the correct shelf, container, then envelope or reel
inside the container. We need to store similar parts together in the
storeroom, to make the most of the containers. For example, SMD resistor
reels are stored together, with a number of different resistor values in
each container. This means SMD resistor part numbers must form a sequence,
though not necesarily in order of ohms value.
A part number should at least tell roughly what kind of part it is - SMD
resistor, leaded electrolytic, etc, so that means the leftmost characters
should carry that info so the sorted list is by part type.
Now, does anyone have a system like that ? Or a different or better system
?
thanks
Roger Lascelles
John Devereux
> Since part numbers are entered by hand over and over again into computer
> systems the key is to use the smallest number of digits possible.
>
> Part numbers should not attempt to define the part.
>
> I would suggest a 6 digit system xxyyyy where xx is a gross identifier and
> yyyy is just a sequential number within the xx class.
>
> Do not use dashes or periods in the part number - that is just one more
> keystroke to enter.
>
> Do not use Alpha characters - you should be able to enter the part number
> with a key pad for speed.
Yes, that is just how I reasoned when setting up our database. Our
part numbers start from 1. Maybe I took the principle too far...
We are up to 1654 now. (BFS17W, a NPN RF transistor. Nice part.)
--
John Devereux
Mark
incomprehensible to a human. Untold hours are wasted looking up part
nmbers.
I suggest you invent a part number that is descriptive such as
RES 1000 Ohms 1/8 W 5% 0402 SMD Rev 3
This ASCII string can BE THE PART NUMBER.
You can add as many fields as needed to completely describe the part
Computers don't need random digits to be the part number. They work
fine with ASCII strings.
I would be glad to work with you to invent this new part number system.
We can both become millionaires.
Mark
Dan Hollands
systems the key is to use the smallest number of digits possible.
Part numbers should not attempt to define the part.
I would suggest a 6 digit system xxyyyy where xx is a gross identifier and
yyyy is just a sequential number within the xx class.
Do not use dashes or periods in the part number - that is just one more
keystroke to enter.
Do not use Alpha characters - you should be able to enter the part number
with a key pad for speed.
--
Dan Hollands
1120 S Creek Dr
Webster NY 14580
585-872-2606
Quick...@USSailing.net
www.QuickScoreRace.com
"Roger Lascelles" <despam...@aanet.com.au> wrote in message
news:1118145239.8b1b814e3565d3cb1c58b5148a78fa1f@teranews...
Boris Mohar
wrote:
>Since part numbers are entered by hand over and over again into computer
>systems the key is to use the smallest number of digits possible.
There is also copy and paste.
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca
void _-void-_ in the obvious place
RST Engineering (jw)
35 years ago, when I started RST Engineering, I was restricted to numbers
below the integer-based storage of the computer we had at the time, so all
of our part numbers were 64,000 and below. (+32K to -32K and a subtraction
algorithm that made them all positive).
Fifteen years ago we switched to a 9-digit part number and what a pain in
the labonza to change them all over. However, change them we did and it has
made life one hell of a lot easier.
Send me a decent email address to jim at rstengineering point com and I'll
port you back our internal company document on how the system works.
Basically, it is a number like 1-2345-6789 where the first digit is a broad
class (mechanical component, electrical component, in house made component,
subassembly, etc.), the 23 is a very generic class of parts (and for
electrical parts, 90% of our stock, based on the first two digits of the
Electronic Engineers Master [EEM] numbering system), the 4 breaks it down to
through-hole, smd, etc., 5 breaks it down further (quarter watt, half watt),
the 6 is the tolerance, the 789 is the value in milliohms with the 7 being
the multiplier and the 89 being the significant digits.
The more I think about it, the better I like the first character being a
letter. That gives me 52 options PLUS the 20 some oddball categories of
@#%& non-alpha characters.
Drop me a line. You might also look at a program called Parts & Vendors
that handles this sort of numbering system quite well.
Jim
"Roger Lascelles" <despam...@aanet.com.au> wrote in message
news:1118145239.8b1b814e3565d3cb1c58b5148a78fa1f@teranews...
Richard Henry
"Mark" <mako...@yahoo.com> wrote in message
news:1118156165.5...@f14g2000cwb.googlegroups.com...
Agree, if it is smart enough to know that
RES 1.0 KOhms 1/8 W 5% 0402 SMD Rev 3
can be the same part.
Spehro Pefhany
Not to mention 1K0
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
Joerg
> We are up to 1654 now. (BFS17W, a NPN RF transistor. Nice part.)
And dirt cheap. My impression is that many young engineers don't even
know about these anymore.
Regards, Joerg
John Devereux
> Hello John,
>
> > We are up to 1654 now. (BFS17W, a NPN RF transistor. Nice part.)
>
> And dirt cheap. My impression is that many young engineers don't even
> know about these anymore.
Yes, that too :) Good job too since I just ordered a reel of 3k. A
lifetime supply at the rate we will use them!
Well, it would be if not for RoHS (as discussed in another thread...)
--
John Devereux
Dan Hollands
enter the part number. They may enter it into a bill of material but thats
about it.
Manufacturing and Purchasing are the groups that spend lots of time entering
part numbers over and over again. When parts are ordered, received, removed
from stock etc. Long alph numeric part numbers not only take more time to
enter but the increase the probability of error.
It is important to get it right from the start. Changing the system later is
a major pain.
The ideal system uses sequential numeric part numbers linked to a
standardized description field. Then reports can be generated for the
engineers that have similar parts grouped together. This makes it easy to
know what parts are already stocked as new products are designed reducing
the rate at which new parts are brought into the system.
A standardized description field is designed for each type of component such
RES 5W 104 SM
It takes considerable work to standardize the descriptions and enforce their
use but is well worth the trouble.
Dan
--
Dan Hollands
1120 S Creek Dr
Webster NY 14580
585-872-2606
Quick...@USSailing.net
www.QuickScoreRace.com
"Mark" <mako...@yahoo.com> wrote in message
news:1118156165.5...@f14g2000cwb.googlegroups.com...
Joel Kolstad
You have some good insights, but let me add a couple of things:
1) One of the biggest frustrations I've had as a working engineer at a small
handful of companies is that many systems used for entering BOMs are some
horribly old archaic pieces of software that have rotten search facilities. A
smart design would let something like "res 2.2k" find any of "resistor
002.2kilohms" "r 2.2 kohms" or "res 2.2kilohms", yet most have limited exact
search functionality much less the "fuzzier" search needed to find "r 2.2
kohms".
> A standardized description field is designed for each type of component such
> RES 5W 104 SM
The problem with this is that you can never foresee all the fields you need.
In a reasonably sophisticated manufacturing operator, something like 99% of
your resistors will be something like "10k, 5%, 0805," but there's always that
design where things like temperature coefficients, the build style (inductive,
non-inductive, etc.) matters. This gets even worse with capacitors.
I've had more than one product fail during production due to someone deciding
that they could go and substitute some "run of the mill" part for something
that had tight specs. To avoid that I sometimes will go to the effort to find
a part where the "standard" description (e.g., 2.2uF 0805 25V) specifically
_isn't_ "in the system!"
> It takes considerable work to standardize the descriptions and enforce their
> use but is well worth the trouble.
...and even with the exceptions to the rules, it's still a lot easier than not
making the attempt.
---Joel Kolstad
Tim Hubberstey
> Engineers often like descriptive part numbers because they rarely have to
> enter the part number. They may enter it into a bill of material but thats
> about it.
>
> Manufacturing and Purchasing are the groups that spend lots of time entering
> part numbers over and over again. When parts are ordered, received, removed
> from stock etc. Long alph numeric part numbers not only take more time to
> enter but the increase the probability of error.
>
> It is important to get it right from the start. Changing the system later is
> a major pain.
>
> The ideal system uses sequential numeric part numbers linked to a
> standardized description field. Then reports can be generated for the
> engineers that have similar parts grouped together. This makes it easy to
> know what parts are already stocked as new products are designed reducing
> the rate at which new parts are brought into the system.
>
> A standardized description field is designed for each type of component such
>
> RES 5W 104 SM
>
> It takes considerable work to standardize the descriptions and enforce their
> use but is well worth the trouble.
I agree completely. I once thought "engineer readable" part numbers were
necessary and designed my own system where the part number encoded all
sorts of useful (to me) info. This ended up being a nightmare because
the person assigning the numbers had to keep coming to me to check that
new numbers were correct. Then there were the situations that I hadn't
thought of, or were ambiguous. In the end, it generated more work for
many people and didn't really improve anything.
If I had to do it again, I would choose a system based on purchasing,
inventory, and manufacturing requirements. I'd probably use 2-3 digits
to define broad categories (mechanical, electrical, etc.), 1-2 digits
for special handling requirements (ESD sensitivity, fragility, humidity,
temperature, etc.) and 5-7 digits for a sequential stock number. I'd
also include a check digit or two to help detect entry errors
(particularly transpositions [430 instead of 403] and phone/calculator
substitutions [143 instead of 749]).
I would use numbers with fields separated by dashes. This is both human
(numeric keypad) and "barcode" friendly. Dashes reduce human error by
breaking numbers into subunits that fit into our short-term memory.
Numeric+dashes allows use of the less error prone (and shorter)
numeric-only barcodes. Check digits are also required to detect read
errors for most barcodes, so including it everywhere keeps the number
consistent.
Initial entry of the standardized descriptions should be
software-verified, or menu-driven. If the description doesn't match an
established template, it should require someone with management-level
authority to enter an override code. Systems that allow entry without
checks are a recipe for enormous headaches. I would also include a
free-form notes field to help cover those special cases nobody thought of.
--
Tim Hubberstey, P.Eng. . . . . . Hardware/Software Consulting Engineer
Marmot Engineering . . . . . . . VHDL, ASICs, FPGAs, embedded systems
Vancouver, BC, Canada . . . . . . . . . . . http://www.marmot-eng.com
Joerg
> Manufacturing and Purchasing are the groups that spend lots of time entering
> part numbers over and over again. When parts are ordered, received, removed
> from stock etc. Long alph numeric part numbers not only take more time to
> enter but the increase the probability of error.
That is exactly the point. You need to be able to enter the PN with just
a numeric keypad. Also, in most companies it needs to be suitable for
bar coding.
> It is important to get it right from the start. Changing the system later is
> a major pain.
In a controlled environment you can't change them later. This can easily
require an ECO re-release of everything that had been designed to date.
Regards, Joerg
Mark
>part numbers over and over again. When parts are ordered, received, removed
>from stock etc. Long alph numeric part numbers not only take more time to
>enter but the increase the probability of error.
Please explain why:
4387645237-045893-001
is less error prone compared to :
RES 1000 Ohms 1/8 W 5% 0402 SMD Rev 3
There's the old story about an army guy that ordered a small audio
transformer to repair a radio and he slipped up on one digit in the
part number.
The transformer finally arrived.. on a flat bed trailer truck. and was
big enough to power a small city.
As far as unforseen variations, you can alway append a small sequence
number at the end as I did using Rev 3 as an example.
Mark
Tim Wescott
I would suggest that you don't even try to organize the storeroom by
part number. If you do then you will have to dedicate enough space for
each part to accept the maximum amount you may ever have on hand -- and
when you add one miserable little part you'll have to rearrage the whole
room.
Any 1/2-way decent stock tracking program will allow you to track the
locations of any parts, and to print pick tags with the location for the
stock boys. Use one, put the parts where it makes sense, ask the
computer when you're looking for parts and tell the computer when you
move them.
--
-------------------------------------------
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
JeffM
>>linked to a standardized description field.
>>Then reports can be generated for the engineers
>>that have similar parts grouped together.
>> Joel Kolstad
>>
Bingo!
>...fields separated by dashes.
>This is both human (numeric keypad) and "barcode" friendly.
>Dashes reduce human error
>by breaking numbers into subunits that fit into our short-term memory.
> Tim Hubberstey
>
Yup.
.
.
>Initial entry of the standardized descriptions
>should be software-verified, or menu-driven.
>If the description doesn't match an established template...
>Systems that allow entry without checks
>are a recipe for enormous headaches.
>
Bang-on. BTDTGTTS
Back in the dark ages, our department had 2 copies of the Parts Book:
1 sorted by P#; 1 sorted by description.
Trying to find parts by Description,
it was obvious that the Co. had started with a system
but (over time) the gatekeeper function had been abandoned.
BAD MANAGEMENT DECISION.
(The Co. had also started with a P#-is-indicative system,
but abandonded that--perhaps at the same time.)
Adrian Jansen
> We are a small company, and we would like to implement a better components
> numbering scheme.
Suggest you go find out about relational database design. Once you
understand how that works, most of what you want is easy to implement.
Look for keywords like 'Natural key' 'Surrogate key' '1 to many
relationship'.
--
Regards,
Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.
Pooh Bear
One of the best I've ever seen, used at a pro-audio manufacturer used a typical
prefix and and sub-descriptor suffix follwed by the value.
E.g. RA100K0 was a 2% 1/4W metal film resistor with value = 100k
RA033R0 was 33R in the same type. Note the use of 4 numerals in both cases to
make listings consistent.
RB, RC etc were different families of resistor type / tolerance / rating etc.
Simialar method used for other parts.
I like the text string idea too. But you need to keep to the format - and that
may be rather less easy to remember.
Graham
Joel Kolstad
news:42A63881...@hotmail.com...
> One of the best I've ever seen, used at a pro-audio manufacturer used a
typical
> prefix and and sub-descriptor suffix follwed by the value.
>
> E.g. RA100K0 was a 2% 1/4W metal film resistor with value = 100k
So what's a 10% 100k resistor? RB100K ???
I tend to waffle about it, but usually I figure that arbitrary numbers are
best -- it doesn't seem there are that many cases where "100k" is the _only_
piece of information you'd like to know about the part, in which case you have
to look up the rest anyway.
Joerg
> I tend to waffle about it, but usually I figure that arbitrary numbers are
> best -- it doesn't seem there are that many cases where "100k" is the _only_
> piece of information you'd like to know about the part, in which case you have
> to look up the rest anyway.
At the end it all boils down to how well the search functions on a parts
database work. For example if you start a new design you may want to
know what kinds of SOT23 transistors are already released and which ones
are used on current products. This ensures that you get to share in all
the candy that Purchasing receives from the vendors before Christams ;-)
Regards, Joerg
Ken Smith
Richard Henry <rph...@home.com> wrote:
[...]
>RES 1.0 KOhms 1/8 W 5% 0402 SMD Rev 3
It goes without saying that there is no need to set up a part number for
5% SMT resistors since the 1% don't cost enough more to matter to anyone
but the truly mass producers.
I think "R 1K0 0402" would be all you'd really need. "1K0" vs "1K00"
would indicate 5% vs 1%. Except for some special cases, the package size
gives the power rating.
--
--
kens...@rahul.net forging knowledge
Roger Lascelles
news:42a61edc$1...@duster.adelaide.on.net...
> Roger Lascelles wrote:
> > We are a small company, and we would like to implement a better
components
> > numbering scheme.
>
> Suggest you go find out about relational database design. Once you
> understand how that works, most of what you want is easy to implement.
> Look for keywords like 'Natural key' 'Surrogate key' '1 to many
> relationship'.
>
> --
> Regards,
>
> Adrian Jansen
If we had a part number to shelf & bin lookup on a database, we could keep
all the resistor 1% SMD reels on the same shelf, even though the part
numbers are simple numbers. That means our storeroom makes best use of
space. We could print out some sheets which let us do the lookup without a
computer in the storeroom. We could even keep our existing parts numbers,
warts and all and reorganise the parts on the shelf.
I'm just not sure that we are big enough to keep it all going. The stock
guy is has got a lot of other work to do already and is a hands-on sort of
guy. There are just 6 or 7 of workers. If I want a part, I wander into the
storeroom and get it.
I think the choices are becoming clear :
- reassign all part numbers in a way which lets us store parts by number.
This system is simple, but storage by part number can still come unstuck as
time changes parts and storage.
- use a database to connect part numbers to shelf locations. This is the
ultimate system but requires discipline.
Thanks, Adrian.
mrob...@worldnet.att.net
>We are a small company, and we would like to implement a better components
>numbering scheme.
Here are the ways a couple of big companies have done it. I'm not
suggesting that these are optimal for you, just giving some examples.
General Electric major appliance part numbers are (were?) of the form
W[A-Z][0-9]{1,2}X[0-9]{1,4}
The leading "W" is constant and I am told it stands for "white goods" -
refrigerators, washing machines, etc. ("Brown goods" are TVs, stereos,
etc... they had a leading "E".)
The second letter indicates what type of product the part is for. R=
refrigerator, B=oven, E=dryer, H=washer, etc. X was used for common
parts like screws, washers, and bolts that could be used in many
different products.
The next two digits indicate a major subsystem or group of related parts
on the machine. For example, in refrigeration, timers are 9, and
compressors are 87.
The "X" was a fairly constant separator. Historically it was the only
separator, but "J" and "M" have also been included in newer part
numbers.
The last one to four digits are just a serial number to tell the parts
apart - they don't encode any characteristics of the part. About the
only thing you could tell from these numbers is that newer parts had
bigger numbers.
People typically didn't pad the numbers (WR9X330) but the computers did
(WR09X0330). The lookup was smart enough to accept either style and
find the right part. The "canonical" form was all upper case, but as
far as I remember, it was case insensitive... wr9x330 or wR9x330 would
all be acceptable to the computer as the same part number.
Volkswagen automotive part numbers are described at
http://www.type2.com/library/identifi/numsys.htm . This system was
probably originally designed with Hollerith cards in mind!
The parts list for an old Systron-Donner frequency counter I have shows
parts with a leading letter and four or five digits. The leading letter
mostly corresponds to the part type: (R)esistor, (C)apacitor (no
distinction between ceramic, electrolytic, etc), (S)witch, X for
sockets, (V)acuum tube, CR for diodes, etc. Integrated circuits and
transistors seem to have all-numeric part numbers. The digits just seem
to be assigned in order of use.
My response to a couple of other points that have been brought up:
Allowing upper case and lower case letters in your part numbers does
double the number of possible values in each digit, but IMHO will drive
you crazy. If nothing else, most existing part numbering schemes are
case insensitive, and you may tend to confuse people if they assume
your scheme is the same. I think it won't be obvious to a lot of people
that an A0123 and an a0123 are two totally different items.
The two extremes of part numbering are probably an all-numeric part
number that has no inherent meaning (73853), and an alphanumeric string
that tries to describe everything about the part (RES 1K 0.5W 5% METAL
FILM). Both of them will drive you crazy. The all-numeric ones are too
easy to confuse with one another. The alphanumeric string only works if
you rigidly enforce some standard when you're putting new parts into the
system, which never happens.
One slight advantage to the all-number system is that these are easy to
copy correctly over the telephone. An alphanumeric system is harder to
communicate - was that a D123 or a P123 or a B123? - unless you can train
people to use some kind of phonetic alphabet (Alpha Bravo Charlie, Able
Baker Charlie, etc).
If you have reason to suspect the part numbers may get garbled, or if
you're just paranoid, you can include a check digit.
It may be helpful for the humans to include dashes, dots, or spaces in
the part number. A big reason why local phone numbers in the US are
seven digits expressed as three digits, dash, four digits (555-1212) is
that Bell System research showed that most people could remember at most
seven digits, and they remembered the digits better if they were broken
into a couple of groups. The computer can store the numbers without any
of this stuff, but it should accept user input with or without the
dashes, dots, etc.
When you're trying to decide how long to make the number, also consider
how many numbers you will need total. Disk storage is cheap, and adding
one more digit multiplies your total available part numbers by at least
10 or 26 or 36. If you later discover that the part numbers are too
short and you need to go back and add more digits, this can range from
trivial to painful (usually the latter) depending on the software. It
may be smart to "waste space" now to save pain later.
If I were trying to do this from scratch for electronic components, I
might do something like this:
[A-Z]-[0-9][0-9]-[0-9][0-9][0-9][0-9]
The initial letter would identify, broadly, the component type:
(R)esistor, (C)apacitor, magic (S)moke, etc.
The next two digits would indicate more attributes of the component.
For resistors, this might include metal film, carbon film, wirewound,
through-hole, SMT, wattage, etc. Maybe this would be just one digit.
The final four digits would just get assigned as needed.
I would create a database to go with this, with the part number as the
primary key of the main table. The main table would also have
additional columns of descriptions that apply to most parts, like
tolerance, through-hole or SMT, and so on. It would also have a
reasonably-sized string field for future use. It's not "clean" design
to have to stick two or three new attributes into this string field
later, but sometimes it beats having to add a column to the table.
There might be other tables for less frequently used descriptions,
also indexed by the part number.
To make the production people happy, one of the pieces of data would be
the part marking for parts that are color coded or too small for a
complete part number. In other words, the list going to production
would say things like "R-42-5309, resistor 1K 5% 0.25 watt metal film,
brown-black-red" or "T-12-8670, transistor 2N2222A surface-mount, 8T5".
A place I worked at also used the Parts and Vendors software that has
been mentioned. I don't know anything about it other than that it
exists and it was possible to run it on several networked computers
accessing a common database.
Whatever database or other software you use, and whatever backup plan you
have, I would also suggest occasionally dumping the part number database
tables to CSV or similar delimited plain-text files. If you need to
change software vendors for whatever reason, most databases can be
persuaded to accept a CSV or delimited-text input. To get your data
into the new database, you might have to change single quotes to double
quotes or escape the commas or whatever, but this is really easy to do
with the right tools, such as awk, sed, perl, and friends on a Unix
system.
I hope this helps!
Matt Roberds
Guy Macon
RST Engineering (jw) wrote:
>The more I think about it, the better I like the first character being a
>letter. That gives me 52 options PLUS the 20 some oddball categories of
>@#%& non-alpha characters.
You might want to avoid easily-confused choices such a 0/O, 1/I, O/Q...
Guy Macon
I worked for a Japanese company that started off with a system
where their part number was whatever the part number of the
vendor who sold it to them was. Of course you can predict what
happened next; two vendors making two parts, both called 98243,
followed by a new numbering system.
I asked them how the system could have possibly worked in Japan,
and they told me they simply asked the vendors not to use the
same part numbers...
Greg Neff
<despam...@aanet.com.au> wrote:
>We are a small company, and we would like to implement a better components
>numbering scheme.
>
>The parts numbers need to go into our accounting system and on parts lists,
>build lists and some schematics, so we don't want them to be too long.
>
>Letters and digits are OK, but each must start with a letter. Sort order is
>a consideration, because computers sort strings from left to right, often in
>ascii or similar order. That means each character position has significance
>and it might be best if every part had the same number of characters.
>
>The storeroom must be organised by part number, so that we can work
>systematically to find the correct shelf, container, then envelope or reel
>inside the container. We need to store similar parts together in the
>storeroom, to make the most of the containers. For example, SMD resistor
>reels are stored together, with a number of different resistor values in
>each container. This means SMD resistor part numbers must form a sequence,
>though not necesarily in order of ohms value.
>
>A part number should at least tell roughly what kind of part it is - SMD
>resistor, leaded electrolytic, etc, so that means the leftmost characters
>should carry that info so the sorted list is by part type.
>
>Now, does anyone have a system like that ? Or a different or better system
>?
>
>thanks
>Roger Lascelles
>
>
>
We have spent a number of years developing and refining our inventory
and production management system. We use sequential part numbers that
have nothing to do with the type of component. Our database system
includes lots of information about each part number that assist in
searching and identification. Each part number can encompass several
different preferred and alternate items. So, we have the top level
part number, and then one or more items under each part number.
For each part number we identify:
Category (resistor, IC, PCB, assembly, chemical, etc.)
Description
Storage location (inventory, offsite storage, hazardous lockup,
fridge, etc.)
Is part warranted, and if so for how long?
Serial number required?
History (pricing, purchasing, receiving, picking)
For each item under each part number we identify:
Manufacturer
Part number
Marking
Link to PDF datasheet
Photograph(s)
We have other stuff in there too, but this gives a good overview.
Our search tool makes a descriptive part number unnecessary. We like
the shorter part number, since there is less chance for error when
entering a part number, and it is quicker to enter. Also, whenever a
part number is entered, the system displays the part description so
that an error can be easily detected.
================================
Greg Neff
VP Engineering
*Microsym* Computers Inc.
gr...@guesswhichwordgoeshere.com
John Larkin
What does the stockroom look like? Do you have smt diodes in one bin
and relay racks in the next?
John
Graham Holloway
"John Larkin" <jjla...@highNOTlandTHIStechnologyPART.com> wrote in message
news:j31ea11g8kv4pjpib...@4ax.com...
I worked for company that operated a system very similar to this. It was
fine for production, I believe. For the engineering design department it was
a farce. So much so, that the lazy ones amongst us could design quicker by
generating a fresh set of parts for each project. Management praise was
forthcoming. But because of over-ordering on each project, the stores
gradually grew and grew. When I investigated I found over 200,000 GBP of
unused stock, some of the parts being of high value due to their age and not
easily usable any more. The manager was not impressed and told me to keep
quiet as it added to the value of the company (although I thought that
auditors would not fall for that one).
My own preference is for a number system that at least includes an initial
digit that classifies the part, e.g. 1=RES, 2=CAP, 3=IC, 4=RECT, with
sub-assemblies being stored with reference to the drawing number system
(start another thread?)
Graham Holloway
RST Engineering (jw)
top assembly number, followed by a four digit part number that is invariant
from model to model.
For example, the chassis hardware subassembly for our audio panel model 564
is
8-0564-2203
The chassis hardware subassembly for our navigation receiver model 523 is
8-0523-2203.
Is that what you had in mind?
Jim
Adrian Jansen
Your goal is always to make it easier. If automation makes it harder,
then you have failed in the implementation. But on the other hand if
your stock guy is the only one who knows where stuff is, and he leaves...
Greg Neff
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>On Wed, 08 Jun 2005 07:51:08 -0400, Greg Neff <gr...@nospam.com> wrote:
>
>>On Tue, 7 Jun 2005 21:53:57 +1000, "Roger Lascelles"
>><despam...@aanet.com.au> wrote:
>>
(snip)
>>
>
>What does the stockroom look like? Do you have smt diodes in one bin
>and relay racks in the next?
>
>John
>
We have areas of different general packaging types (small reel, large
rail, rail, tray, bulk, etc,), and within each area the parts are in
our part number order. This works fairly well, although we sometimes
have to deal with parts in different packages. It's not perfect, but
it's good enough.
Greg Neff
<e...@wps-electronics.demon.co.uk> wrote:
>
>
(snip)
>>
>I worked for company that operated a system very similar to this. It was
>fine for production, I believe. For the engineering design department it was
>a farce. So much so, that the lazy ones amongst us could design quicker by
>generating a fresh set of parts for each project. Management praise was
>forthcoming. But because of over-ordering on each project, the stores
>gradually grew and grew. When I investigated I found over 200,000 GBP of
>unused stock, some of the parts being of high value due to their age and not
>easily usable any more. The manager was not impressed and told me to keep
>quiet as it added to the value of the company (although I thought that
>auditors would not fall for that one).
>
>My own preference is for a number system that at least includes an initial
>digit that classifies the part, e.g. 1=RES, 2=CAP, 3=IC, 4=RECT, with
>sub-assemblies being stored with reference to the drawing number system
>(start another thread?)
>
>
>Graham Holloway
>
It sounds like engineering didn't have any constructive input to the
system. Clearly, an engineer wants nothing to do with meaningless
part numbers. To alleviate this problem, we handle engineering part
selection in a descriptive manner. Our OrCAD part libraries are a
controlled part of our inventory system. If I need a 1K 5% 0402
resistor, I open the RES_SMD_0402 library, and select 'R 1K 5% 0402'
from that library. Nothing hard about that. Each part in each OrCAD
library must include a field that is our unique part number. If we
don't have 'R 1K 5% 0402' in the library, then we generate a new part
number in the system and then generate the part in the OrCAD library.
Generic library parts are prohibited.
When we generate the BOM, we include our part number field. Our
inventory control system scans the BOM into the system. Once it's in
the system, we can generate work orders for x number of that assembly,
including inventory pick lists, buy lists, etc.
PN2222A
"Roger Lascelles" <despam...@aanet.com.au> wrote in message
news:1118145239.8b1b814e3565d3cb1c58b5148a78fa1f@teranews...
> We are a small company, and we would like to implement a better components
> numbering scheme.
>
Just use the Digikey number.
If it can't be bought from digikey, you shouldn't be using it in your
design.
Now, you might just have to move to the USA, but ...
PN2222A
Digikey p/n 497-2406-ND
Paul Burke
> Just use the Digikey number.
What do we do in the UK, where Digikey have left out 50 or so pages from
this year's catalogue?
Paul Burke
R Adsett
bip...@lithium.net says...
What do you do when more than one Digikey p/n maps to your part spec?
Even in this case I see 12 Digikey P/ns from 7 Manufacturers.
Robert
RST Engineering (jw)
simple 6-digits from the days in the late 1960s when Jerry Mouser was
selling offshore capacitors out of the back of his pickup in San Diego.
Some of their part numbers are the manufacturer's part number prefixed by a
3-digit vendor code. Some of them are 15 digit from God knows where. Look
at their catalog for a good lesson in how to jury-rig a system that you
DON'T want to use.
Jim
Spehro Pefhany
\(jw\)" <j...@rstengineering.com> wrote:
>Just try to keep from emulating Mouser. Some of their part numbers are
>simple 6-digits from the days in the late 1960s when Jerry Mouser was
>selling offshore capacitors out of the back of his pickup in San Diego.
>Some of their part numbers are the manufacturer's part number prefixed by a
>3-digit vendor code. Some of them are 15 digit from God knows where. Look
>at their catalog for a good lesson in how to jury-rig a system that you
>DON'T want to use.
>
>Jim
Thank goodness he didn't choose to prefix every P/N with "ND" or
something silly like that.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
John Larkin
<spef...@interlogDOTyou.knowwhat> wrote:
>On Fri, 10 Jun 2005 08:58:50 -0700, the renowned "RST Engineering
>\(jw\)" <j...@rstengineering.com> wrote:
>
>>Just try to keep from emulating Mouser. Some of their part numbers are
>>simple 6-digits from the days in the late 1960s when Jerry Mouser was
>>selling offshore capacitors out of the back of his pickup in San Diego.
>>Some of their part numbers are the manufacturer's part number prefixed by a
>>3-digit vendor code. Some of them are 15 digit from God knows where. Look
>>at their catalog for a good lesson in how to jury-rig a system that you
>>DON'T want to use.
>>
>>Jim
>
>Thank goodness he didn't choose to prefix every P/N with "ND" or
>something silly like that.
>
>
"No Discount" I think.
John
Rich Grise
> Just try to keep from emulating Mouser. Some of their part numbers are
> simple 6-digits from the days in the late 1960s when Jerry Mouser was
> selling offshore capacitors out of the back of his pickup in San Diego.
> Some of their part numbers are the manufacturer's part number prefixed by a
> 3-digit vendor code. Some of them are 15 digit from God knows where. Look
> at their catalog for a good lesson in how to jury-rig a system that you
> DON'T want to use.
>
>>> Just use the Digikey number.
>>> If it can't be bought from digikey, you shouldn't be using it in your
>>> design.
Or, you could go with the Federal Stock Number, which I've heard has
been changed to the NATO Stock Number. I've also heard that their
nubering system was based on the Sears Roebuck & Co. stock numbering
system.
I worked for awhile at a place where their stock numbers were the
Julian Date that the part spec. got approved, and a sequence number.
It was a nightmare for us techies - of course us techies want vendor
numbers - that's why you need a decent relational database and an
understanding of how they work.
Good Luck!
Rich