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Bill, My preference is to "design in" safety while staying mindful of EMC. Although it is not possible to accurately predict exactly how a change will affect EMC, it is generally much easier to do so with safety. Also, safety is much less a "black art" than EMC which means you can train mechanical and electrical engineers to build in safety constraints.
EMC is possibly job security for the compliance engineer with agency liaison and standards research a close second. Still, I like to think there are certain rules of thumb that help me to anticipate risks to EMC with design changes. So, the idea of concurrent design with Mechanical, Electrical, Process and Compliance engineers working together can certainly be a reality for safety and possibly for EMC as well. All too often EMC is left for dead last and then expensive product turns are a risk. At the very least, heroic efforts are made to solve EMC issues at the skins of the enclosure (e.g. EMI filters, Cu tape, gasketing, filtered I/O) when they better solved at the source of the problem, down inside the box. Regards, -doug Douglas E. Powell Staff Engineer Corporate Compliance Dept. Advanced Energy Industries, Inc. Fort Collins, CO 80525 USA end From: FastWave [mailto:[email protected]] Sent: Monday, March 29, 2004 9:48 AM To: [email protected] Subject: Safety & EMC - which 1st? Fellow Compliance Engineers, Certainly we would all prefer that our company's products be designed for initial/immediate compliance, that we have multiple samples available for testing, and that all the testing is completed without failure. However, in the real world scenario of one sample for both safety & EMC, that may not pass all tests, would you recommend that safety certification/testing be done before or after EMC testing? The key issue being whether a "fix" for one discipline will require a re-test for the other discipline. Personally, I have always recommended that safety be done 1st for two reasons: 1) Changes for safety almost always affect EMC testing but EMC changes seldom affect safety testing and, 2) Safety re-tests are far less expensive than EMC re-tests. Do you agree? Any there any other philosophies on this topic? Thanks for your input, Bill Bisenius E.D.& D. [email protected] <mailto:[email protected]> This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstcTitle: RE: Safety & EMC - which 1st?
Bill,
My preference is to "design in" safety while staying mindful of EMC.
Although it is not possible to accurately predict exactly how a change
will affect EMC, it is generally much easier to do so with safety.
Also, safety is much less a "black art" than EMC which means you can
train mechanical and electrical engineers to build in safety
constraints.
EMC is possibly job security for the compliance engineer with agency
liaison and standards research a close second. Still, I like to think
there are certain rules of thumb that help me to anticipate risks to EMC
with design changes.
So, the idea of concurrent design with Mechanical, Electrical, Process
and Compliance engineers working together can certainly be a reality for
safety and possibly for EMC as well.
All too often EMC is left for dead last and then expensive product turns
are a risk. At the very least, heroic efforts are made to solve EMC
issues at the skins of the enclosure (e.g. EMI filters, Cu tape,
gasketing, filtered I/O) when they better solved at the source of the
problem, down inside the box.
Regards,
-doug
-------------------------------------
Douglas E. Powell
Staff Engineer
Corporate Compliance Dept.
Advanced Energy Industries, Inc.
Fort Collins, CO 80525 USA
end
-----Original Message-----
From: FastWave [mailto:[email protected]]
Sent: Monday, March 29, 2004 9:48 AM
To: [email protected]
Subject: Safety & EMC - which 1st?
Fellow Compliance Engineers,
Certainly we would all prefer that our company's products be designed
for initial/immediate compliance, that we have multiple samples
available for testing, and that all the testing is completed without
failure. However, in the real world scenario of one sample for both
safety & EMC, that may not pass all tests, would you recommend that
safety certification/testing be done before or after EMC testing? The
key issue being whether a "fix" for one discipline will require a
re-test for the other discipline.
Personally, I have always recommended that safety be done 1st for two
reasons:
1) Changes for safety almost always affect EMC testing but EMC
changes
seldom affect safety testing and,
2) Safety re-tests are far less expensive than EMC re-tests.
Do you agree? Any there any other philosophies on this topic?
Thanks for your input,
Bill Bisenius
E.D.& D.
[email protected] <mailto:[email protected]>
-------------------------------------------
This message is from the IEEE EMC Society Product Safety Technical
Committee emc-pstc discussion list.
Visit our web site at: http://www.ieee-pses.org/
To cancel your subscription, send mail to:
[email protected]
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Ron Pickard: [email protected]
Dave Heald: [email protected]
For policy questions, send mail to:
Richard Nute: [email protected]
Jim Bacher: [email protected]
All emc-pstc postings are archived and searchable on the web at:
http://www.ieeecommunities.org/emc-pstc
ATT31822.txt
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