We use DPMO / PPM at our inspection step, and %yield at test. We're not
following 7912 exactly, but pretty close.

I don't think it is really important how you get the measures, but how
you use them. When looking for improvement opportunities, we look at
essentially defects per board as opposed to PPM. This is because a small
run of a low volume product with a few defects would have a high PPM,
but our high volume boards could have more defects and more
opportunities even though they have a lower PPM.

Blair Hogg
QA Manager
GAI-Tronics

>>> [log in to unmask] 10/01/03 05:22PM >>>
Hi everyone,

The upper management team here uses a DPU metric for our board shop,
for
what reason I am trying to comprehend.  Basically, one solder joint
defect
on a board equates to the whole board counting as a defect.  The
opportunities are irrelevant - every board gets one opportunity.  When
the
"PPM" numbers are published, which is what they call them, they are
outrageously high.  My questions are:
Does anyone use Defects per Unit at the board level?
If so, what kind of numbers are you seeing.?

I am pursuing a change to use real DPMO metrics, but so far I've been
unsuccessful.  I even presented IPC-7912, but it was ignored.  Thanks
in
advance for the help.

Howard Watson
SMT Manufacturing Engineer
AMETEK/Dixson
Grand Junction, CO



**********************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom they
are addressed. If you have received this email in error please notify
the system manager.

This footnote also confirms that this email message has been swept
for the presence of computer viruses.

www.hubbell.com - Hubbell Incorporated
**********************************************************************

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------