Hi Brian:
In 1998, I wrote a column, Technically Speaking,
in the Product Safety Newsletter that addresses
this topic. See attached.
(Since the listserver does not accept attachments,
subscribers should e-mail a request to me.)
Best regards,
Rich
From: Kunde, Brian [mailto:[email protected]]
Sent: Friday, November 04, 2016 7:38 AM
To: [email protected]
<mailto:[email protected]>
Subject: [PSES] AC Mains Outlet fuses or daul pole
breaker??
Greetings Experts.
If we send 230Vrms out of a product to power an
external device through an IEC Outlet connector
and we need to provide Overcurrent Protection for
this port internal to our device, can I use two
fuses or do I have to use a double pole circuit
breaker?
Since our product can be used in a 220-230 Vrms
power system which cannot guarantee polarity on
the plug (such as Europe) or that the neutral will
be grounded (some North American power systems for
example), we have to have over-current protection
on BOTH sides of the line (all current carrying
conductors).
But when we supply power externally to another
device, it is possible that one fuse could open
and the other side of the line is HOT to Earth.
Someone working on the external device could put a
meter across the line as see there is no voltage
and assume the AC mains is OFF not knowing that
one side of the line it still HOT to Earth. This
could cause a hazardous condition.
SO, this is the reason for my question. If our
device supplies power externally to another
device, can we use fuses which could cause the
hazardous condition I explained above, OR must we
use a Double Pole Circuit Breaker which opens all
HOT conductors simultaneously? If I must use a
breaker, what standard or rule dictates this
requirement?
OR is this even a scenario we have to be concerned
about? Since the external device has a warning
label to disconnect power cord before servicing,
is this even something to be concerned about?
BTW, my product is Laboratory Equipment (UL/IEC
61010-1) to sell on a worldwide market.
Thanks,
The Other 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:
http://www.ieee-pses.org/emc-pstc.html
Attachments are not permitted but the IEEE PSES Online Communities site at
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used
formats), large files, etc.
Website: http://www.ieee-pses.org/
Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe)
List rules: http://www.ieee-pses.org/listrules.html
For help, send mail to the list administrators:
Scott Douglas <[email protected]>
Mike Cantwell <[email protected]>
For policy questions, send mail to:
Jim Bacher: <[email protected]>
David Heald: <[email protected]>
