Hi Peter:
> > I am looking at EN 60204-1, §C.1.3, and Table C.2. Am I
> > correct in interpreting C.1.3, first dashed paragraph, the
> > phrase "one loaded three-phase a.c. cable system ..." to mean
> > all phase conductors of a three-phase system loaded
> > simultaneously and equally (balanced load)? I note that the
> > top-right-most column heading for derating factors in Table
> > C.2 is labeled "Number of loaded cables/conductors," which
> > leads me to question my original interpretation.
My interpretation is that C.1.3 has derating
requirements for both three-phase power and
single-phase (two-conductor) power. Figure
C.1 shows various configurations of conductors
for both three-phase and single-phase.
The derating is based on one loaded three-phase
cable, or one loaded single-phase (loaded pair)
cable. Derating of a three-phase cable when
only one phase is loaded doesn't make much
sense.
My conclusion is that all the phase conductors
are loaded simultaneously and equally. The
illustrations have only three wires, which
means either a three-phase delta or a balanced
three-phase wye with zero neutral current (in
which case the neutral plays no part in the
derating).
Best regards,
Rich
ps: IEC 60204 is not a standard that is in
common use by safety engineers.
-
This message is from the IEEE Product Safety Engineering Society
emc-pstc discussion list. Website: http://www.ieee-pses.org/
To post a message to the list, send your e-mail to emc-p...@ieee.org
Instructions: http://listserv.ieee.org/request/user-guide.html
List rules: http://www.ieee-pses.org/listrules.html
For help, send mail to the list administrators:
Scott Douglas emcp...@ptcnh.net
Mike Cantwell mcantw...@ieee.org
For policy questions, send mail to:
Jim Bacher: j.bac...@ieee.org
David Heald: emc-p...@daveheald.com
All emc-pstc postings are archived and searchable on the web at:
http://www.ieeecommunities.org/emc-pstc
______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________
