Admittedly it is "out of context" (and refers to "impulsive, wide band,
emission)  but you might use the precedent of CISPR14 "Emission . Household
Appliances, electric tools and similar apparatus" which has a section 4.2
covering "Discontinuous Disturbances".

 

It is worth a look - but too detailed to summarise here.

 

 

Richard

 

Richard Marshall Laboratories,

30 Ox Lane, Harpenden, Herts.,    AL5 4HE, UK 

+44 (0)1582 460815      <http://www.design-emc.co.uk> www.design-emc.co.uk

Member of the EMC Industry Association

 

From: Pawson, James [mailto:james.paw...@echostar.com] 
Sent: 26 March 2015 15:02
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Quasi Peak - Length of Measurement Time for Final Spot
Measurement?

 

Dear group,

 

When measuring emissions using a Quasi Peak detector are there any
regulations or guidance concerning the amount of time one should dwell on a
single frequency for a measurement?

 

I know it depends on the nature of the signal. In this case, the signal of
interest results in a burst of emissions of a high duty cycle followed by a
long period (i.e. several minutes) of low duty cycle activity. If I use a QP
detector and measure for 1 second just as the burst happens then I would get
a high QP reading. If I measure in the steady state period I would get a
lower QP reading.

 

In this case, knowing the signals involves, would the intention to be to
measure

 

1.       one full representative cycle of emissions i.e. the initial burst
and the low duty period after

2.       during the maximum duty cycle only

3.       during the steady state only

 

I can imagine that the measurement difference between 1) and 3) in this case
would be small as the level measured during the high duty period would have
had time to decay down to the same level as the steady state due to the QP
time constant.

 

I'm asking this question in the context of both EN 55022 and FCC 15.

 

Googling for "quasi peak measurement time" and similar phrases is not
proving helpful

 

Many thanks

James Pawson

 

-
----------------------------------------------------------------

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
<emc-p...@ieee.org <mailto:emc-p...@ieee.org> >

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) <http://www.ieee-pses.org/list.html> 
List rules: http://www.ieee-pses.org/listrules.html 

For help, send mail to the list administrators:
Scott Douglas <sdoug...@ieee.org <mailto:sdoug...@ieee.org> >
Mike Cantwell <mcantw...@ieee.org <mailto:mcantw...@ieee.org> > 

For policy questions, send mail to:
Jim Bacher <j.bac...@ieee.org <mailto:j.bac...@ieee.org> >
David Heald <dhe...@gmail.com <mailto:dhe...@gmail.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 
<emc-p...@ieee.org>

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 <sdoug...@ieee.org>
Mike Cantwell <mcantw...@ieee.org>

For policy questions, send mail to:
Jim Bacher:  <j.bac...@ieee.org>
David Heald: <dhe...@gmail.com>

Reply via email to