Typo trouble. It's POWDER coat. Yes, the mask is probably the cause of
the problem. The powder particles can't get underneath it, but the
liquid can, and will. You can check, if you can chemically (not
mechanically) remove any epoxy from the surfaces hat should be bare.
There is probably a trick that seals the edge of the mask to the metal,
so the liquid can't get in, but I don't know what the trick is. It could
be as simple as ordinary grease, but NOT silicone grease, because you
will never be able to get it off the metal.
On 2026-01-29 19:50, Brian Gregory wrote:
Hi folks,
Our bare-metal prototype passed FCC Class B RE with flying colors;
8-12 dB margin.
Now, a fairly similar unit (hey, they're prototypes) whose enclosure
is power coated is now failing by 10-20 dB. The worst failures are
at low frequencies, under 50 MHz, apparently.
Is there anything more complicated we should look at apart from the
powder coat mask not working well enough, such that covers and side
panels aren't properly grounded with all that epoxy ? What else
could account for this difference?
thanks,
Colorado Brian
------------------------------------------------------------------------
This message is from the IEEE Product Safety Engineering Society
emc-pstc discussion list. To post a message to the list, send your
e-mail to [email protected]
All emc-pstc postings are archived and searchable on the web at:
https://www.mail-archive.com/[email protected]/
Website: https://ewh.ieee.org/soc/pses/
Instructions: https://ewh.ieee.org/soc/pses/list.html (including how
to unsubscribe) <https://ewh.ieee.org/soc/pses/list.html>
List rules:
https://pses.ieee.org/wp-content/uploads/2024/12/EM-PSTC-List-Rules.pdf
For help, send mail to the list administrators:
Mike Sherman at: [email protected]
Rick Linford at: [email protected]
For policy questions, send mail to:
Jim Bacher at: [email protected]
------------------------------------------------------------------------
To unsubscribe from the EMC-PSTC list, click the following link:
https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
--
Best wishes John Woodgate RAYLEIGH Essex OOO-Own Opinions Only
www.woodjohn.uk If something is true: * as far as we know - it's science
*for certain - it's mathematics *unquestionably - it's religion
--
This email has been checked for viruses by AVG antivirus software.
www.avg.com
-
----------------------------------------------------------------
This message is from the IEEE Product Safety Engineering Society emc-pstc
discussion list. To post a message to the list, send your e-mail to
[email protected]
All emc-pstc postings are archived and searchable on the web at:
https://www.mail-archive.com/[email protected]/
Website: https://ewh.ieee.org/soc/pses/
Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to
unsubscribe)
List rules:
https://pses.ieee.org/wp-content/uploads/2024/12/EM-PSTC-List-Rules.pdf
For help, send mail to the list administrators:
Mike Sherman at: [email protected]
Rick Linford at: [email protected]
For policy questions, send mail to:
Jim Bacher: <[email protected]>
_________________________________________________
To unsubscribe from the EMC-PSTC list, click the following link:
https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
