Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
But the original problem stated the limit was in terms of magnetic field, and since a loop measures magnetic field directly, there is no problem having to make an assumption about field impedance. It is only when the limit is in terms of electric field but the quantity measured is magnetic field using a loop antenna that the problem Cortland describes is encountered. Ken Javor Phone: (256) 650-5261 From: Cortland Richmond Reply-To: Cortland Richmond Date: Thu, 17 Jan 2019 22:52:57 -0500 To: Subject: Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits The bottom line here is that the usual emission standards don't take into account that the non-radiating near H-field falls off as the cube of distance (an issue with BPL, remember) and the wave impedance in this area is nowhere near 120 Ohms. Measuring at 3 meters using 51.5 dB as a conversion factor just doesn't hack it. Some years ago, I had occasion to look for incremental fall-off with distance from a wheel mounted tire pressure sending unit. EVERYTHING was in the non-radiating near field, but I could find no way to take that into account in the standard. I needed an H-field antenna with curves for that distance not derived from E-fields much farther off. Cortland Richmond Semi retired at Belcan, Grand Rapids MI On 1/17/19 6:22 PM, John Woodgate wrote: > > > Well, no it isn't. The definition of the decibel is based on power, and is > only extended to voltage and current by adding the assumption that the > resistance is constant. There is no formally-correct way of extending it to > resistance and even less to impedance. There is a fatal flaw: Consider > 10*log(W) = 20*log(V) - 10*log(R), but 20*log(V) = 20*log(I) + 20*log(R). The > multiplier is 10 sometimes and 20 at other times. It gets worse rapidly if you > try to accommodate complex impedances. > > > > You can calculate 20*log(Z1/Z2) but you shouldn't call it 'decibels', any more > than if you calculated 20*log(your height/my height). Of course, if you did a > similar calculation for your income/my income, it would have to be > 10*log(yi/mi), because 'money is power'. > > > Best wishes > John Woodgate OOO-Own Opinions Only > J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> > Rayleigh, Essex UK > > On 2019-01-17 22:17, Ken Javor wrote: > > >> Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits It would be >> completely correct to say that the 51.5 dB factor is dB above one ohm, which >> is the difference in magnetic and electric field units. >> >> Ken Javor >> Phone: (256) 650-5261 >> >> >> >> >> From: John Woodgate <mailto:j...@woodjohn.uk> >> Reply-To: John Woodgate <mailto:j...@woodjohn.uk> >> Date: Thu, 17 Jan 2019 22:11:50 + >> To: <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> >> Subject: Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits >> >> >> >> To fill in, that 51.5 dB = 375.84 numerically and comes from the impedance >> of free space, 120*¼ = 376.99 ohms. which is actually 51.5266 expressed in >> 'decibels'. Actually, expressing an impedance in 'decibels' is a illegal >> operation 'but it works, so why bother?'. >> >> >> Best wishes >> John Woodgate OOO-Own Opinions Only >> J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> >> <http://www.woodjohn.uk> >> Rayleigh, Essex UK >> >> On 2019-01-17 21:57, Ken Javor wrote: >> >> >> >>> Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits You are making too >>> much of it. If the limit is in terms of dBuA/m, you use the loop magnetic >>> field antenna factor, which is 51.5 dB less efficient than the loop electric >>> field antenna factor. Of course, this is based on a far field assumption, >>> and that is all you have available. But the magnetic field antenna factor >>> is fundamental; it is the loop electric field antenna factor that is based >>> on the FF assumption, so you need not worry at all. >>> >>> No worries! >>> >>> Ken Javor >>> Phone: (256) 650-5261 >>> >>> >>> >>> >>> >>> From: "Kunde, Brian" >>> <mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com> >>> Reply-To: "Kunde, Brian" >>> <mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com> >>> Date: Thu, 17 Jan 2019 21:27:15 + >>> To: <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> >>> <mailto:EMC-PSTC
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
The bottom line here is that the usual emission standards don't take
into account that the non-radiating near H-field falls off as the cube
of distance (an issue with BPL, remember) and the wave impedance in this
area is nowhere near 120 Ohms. Measuring at 3 meters using 51.5 dB as
a conversion factor just doesn't hack it.
Some years ago, I had occasion to look for incremental fall-off with
distance from a wheel mounted tire pressure sending unit. EVERYTHING was
in the non-radiating near field, but I could find no way to take that
into account in the standard. I needed an H-field antenna with curves
for that distance not derived from E-fields much farther off.
Cortland Richmond
Semi retired at Belcan,
Grand Rapids MI
On 1/17/19 6:22 PM, John Woodgate wrote:
Well, no it isn't. The definition of the decibel is based on power,
and is only extended to voltage and current by adding the assumption
that the resistance is constant. There is no formally-correct way of
extending it to resistance and even less to impedance. There is a
fatal flaw: Consider 10*log(W) = 20*log(V) - 10*log(R), but 20*log(V)
= 20*log(I) + 20*log(R). The multiplier is 10 sometimes and 20 at
other times. It gets worse rapidly if you try to accommodate complex
impedances.
You can calculate 20*log(Z1/Z2) but you shouldn't call it 'decibels',
any more than if you calculated 20*log(your height/my height). Of
course, if you did a similar calculation for your income/my income, it
would have to be 10*log(yi/mi), because 'money is power'.
Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associateswww.woodjohn.uk
Rayleigh, Essex UK
On 2019-01-17 22:17, Ken Javor wrote:
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits It would be
completely correct to say that the 51.5 dB factor is dB above one
ohm, which is the difference in magnetic and electric field units.
Ken Javor
Phone: (256) 650-5261
*From: *John Woodgate
*Reply-To: *John Woodgate
*Date: *Thu, 17 Jan 2019 22:11:50 +
*To: *
*Subject: *Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
To fill in, that 51.5 dB = 375.84 numerically and comes from the
impedance of free space, 120*π = 376.99 ohms. which is actually
51.5266 expressed in 'decibels'. Actually, expressing an impedance in
'decibels' is a illegal operation 'but it works, so why bother?'.
Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk>
<http://www.woodjohn.uk>
Rayleigh, Essex UK
On 2019-01-17 21:57, Ken Javor wrote:
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits You are
making too much of it. If the limit is in terms of dBuA/m, you
use the loop magnetic field antenna factor, which is 51.5 dB less
efficient than the loop electric field antenna factor. Of
course, this is based on a far field assumption, and that is all
you have available. But the magnetic field antenna factor is
fundamental; it is the loop electric field antenna factor that is
based on the FF assumption, so you need not worry at all.
No worries!
Ken Javor
Phone: (256) 650-5261
*From: *"Kunde, Brian"
<mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com>
*Reply-To: *"Kunde, Brian"
<mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com>
*Date: *Thu, 17 Jan 2019 21:27:15 +
*To: *
<mailto:EMC-PSTC@LISTSERV.IEEE.ORG>
<mailto:EMC-PSTC@LISTSERV.IEEE.ORG>
*Conversation: *CISPR11 Rad Magnetic Field Emissions Limits
*Subject: *[PSES] CISPR11 Rad Magnetic Field Emissions Limits
Reference CISPR11/EN55011:2016 version.
If you are an expert at the Radiated Emissions test from 150Khz
-30Mhz for Class A Group 2 equipment, I could really use your help.
I haven’t done this test in over 25 years. I refurbished our
Active Loop antenna and placed it 10 meters from the EUT. I
believe the data values read by our receiver is dBuV/m. However,
the limits as it appears in Table 10 are in dBuA/m. How do I
convert?
I have an old 1999 copy of this standard that shows the limits
with the exact same frequency ranges but the limits are in
dBuV/m. Do I just use these limits or do I have to somehow
convert the receiver data to dBuA/m.
I know a straight conversion between dBuV/m and dBuA/m can be
difficult because above 4Mhz we are in the far-field, but below
that we are getting into the near field. And the impedance
calculation can be difficult to obtain.
Am I making too much of this or just take a simple conversion
based on the differences between the two versio
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
Well, no it isn't. The definition of the decibel is based on power, and
is only extended to voltage and current by adding the assumption that
the resistance is constant. There is no formally-correct way of
extending it to resistance and even less to impedance. There is a fatal
flaw: Consider 10*log(W) = 20*log(V) - 10*log(R), but 20*log(V) =
20*log(I) + 20*log(R). The multiplier is 10 sometimes and 20 at other
times. It gets worse rapidly if you try to accommodate complex impedances.
You can calculate 20*log(Z1/Z2) but you shouldn't call it 'decibels',
any more than if you calculated 20*log(your height/my height). Of
course, if you did a similar calculation for your income/my income, it
would have to be 10*log(yi/mi), because 'money is power'.
Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk
Rayleigh, Essex UK
On 2019-01-17 22:17, Ken Javor wrote:
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits It would be
completely correct to say that the 51.5 dB factor is dB above one ohm,
which is the difference in magnetic and electric field units.
Ken Javor
Phone: (256) 650-5261
*From: *John Woodgate
*Reply-To: *John Woodgate
*Date: *Thu, 17 Jan 2019 22:11:50 +
*To: *
*Subject: *Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
To fill in, that 51.5 dB = 375.84 numerically and comes from the
impedance of free space, 120*π = 376.99 ohms. which is actually
51.5266 expressed in 'decibels'. Actually, expressing an impedance in
'decibels' is a illegal operation 'but it works, so why bother?'.
Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk>
<http://www.woodjohn.uk>
Rayleigh, Essex UK
On 2019-01-17 21:57, Ken Javor wrote:
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits You are
making too much of it. If the limit is in terms of dBuA/m, you
use the loop magnetic field antenna factor, which is 51.5 dB less
efficient than the loop electric field antenna factor. Of course,
this is based on a far field assumption, and that is all you have
available. But the magnetic field antenna factor is fundamental;
it is the loop electric field antenna factor that is based on the
FF assumption, so you need not worry at all.
No worries!
Ken Javor
Phone: (256) 650-5261
*From: *"Kunde, Brian"
<mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com>
*Reply-To: *"Kunde, Brian"
<mailto:brian_ku...@lecotc.com> <mailto:brian_ku...@lecotc.com>
*Date: *Thu, 17 Jan 2019 21:27:15 +
*To: *
<mailto:EMC-PSTC@LISTSERV.IEEE.ORG>
<mailto:EMC-PSTC@LISTSERV.IEEE.ORG>
*Conversation: *CISPR11 Rad Magnetic Field Emissions Limits
*Subject: *[PSES] CISPR11 Rad Magnetic Field Emissions Limits
Reference CISPR11/EN55011:2016 version.
If you are an expert at the Radiated Emissions test from 150Khz
-30Mhz for Class A Group 2 equipment, I could really use your help.
I haven’t done this test in over 25 years. I refurbished our
Active Loop antenna and placed it 10 meters from the EUT. I
believe the data values read by our receiver is dBuV/m. However,
the limits as it appears in Table 10 are in dBuA/m. How do I
convert?
I have an old 1999 copy of this standard that shows the limits
with the exact same frequency ranges but the limits are in dBuV/m.
Do I just use these limits or do I have to somehow convert the
receiver data to dBuA/m.
I know a straight conversion between dBuV/m and dBuA/m can be
difficult because above 4Mhz we are in the far-field, but below
that we are getting into the near field. And the impedance
calculation can be difficult to obtain.
Am I making too much of this or just take a simple conversion
based on the differences between the two versions of the standard?
Thanks for the help.
The Other Brian
*LECO Corporation Notice:**This communication may contain
confidential information intended for the named recipient(s) only.
If you received this by mistake, please destroy it and notify us
of the error. Thank you.
*-
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http://www.ieee-pses.org/emc-pstc.html
Attachments are not permitted but the IEE
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
It would be completely correct to say that the 51.5 dB factor is dB above one ohm, which is the difference in magnetic and electric field units. Ken Javor Phone: (256) 650-5261 From: John Woodgate Reply-To: John Woodgate Date: Thu, 17 Jan 2019 22:11:50 + To: Subject: Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits To fill in, that 51.5 dB = 375.84 numerically and comes from the impedance of free space, 120*¼ = 376.99 ohms. which is actually 51.5266 expressed in 'decibels'. Actually, expressing an impedance in 'decibels' is a illegal operation 'but it works, so why bother?'. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-01-17 21:57, Ken Javor wrote: > Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits You are making too > much of it. If the limit is in terms of dBuA/m, you use the loop magnetic > field antenna factor, which is 51.5 dB less efficient than the loop electric > field antenna factor. Of course, this is based on a far field assumption, and > that is all you have available. But the magnetic field antenna factor is > fundamental; it is the loop electric field antenna factor that is based on the > FF assumption, so you need not worry at all. > > No worries! > > Ken Javor > Phone: (256) 650-5261 > > > > > From: "Kunde, Brian" <mailto:brian_ku...@lecotc.com> > Reply-To: "Kunde, Brian" > <mailto:brian_ku...@lecotc.com> > Date: Thu, 17 Jan 2019 21:27:15 + > To: <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> > Conversation: CISPR11 Rad Magnetic Field Emissions Limits > Subject: [PSES] CISPR11 Rad Magnetic Field Emissions Limits > > Reference CISPR11/EN55011:2016 version. > > If you are an expert at the Radiated Emissions test from 150Khz -30Mhz for > Class A Group 2 equipment, I could really use your help. > > I haven¹t done this test in over 25 years. I refurbished our Active Loop > antenna and placed it 10 meters from the EUT. I believe the data values read > by our receiver is dBuV/m. However, the limits as it appears in Table 10 are > in dBuA/m. How do I convert? > > I have an old 1999 copy of this standard that shows the limits with the exact > same frequency ranges but the limits are in dBuV/m. Do I just use these > limits or do I have to somehow convert the receiver data to dBuA/m. > > I know a straight conversion between dBuV/m and dBuA/m can be difficult > because above 4Mhz we are in the far-field, but below that we are getting into > the near field. And the impedance calculation can be difficult to obtain. > > Am I making too much of this or just take a simple conversion based on the > differences between the two versions of the standard? > > Thanks for the help. > > The Other Brian > > > LECO Corporation Notice: This communication may contain confidential > information intended for the named recipient(s) only. If you received this by > mistake, please destroy it and notify us of the error. Thank you. > - > > > 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 > <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 <mailto:sdoug...@ieee.org> > Mike Cantwell <mailto:mcantw...@ieee.org> > > For policy questions, send mail to: > Jim Bacher <mailto:j.bac...@ieee.org> > David Heald <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 > > > > 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
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
To fill in, that 51.5 dB = 375.84 numerically and comes from the impedance of free space, 120*π = 376.99 ohms. which is actually 51.5266 expressed in 'decibels'. Actually, expressing an impedance in 'decibels' is a illegal operation 'but it works, so why bother?'. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2019-01-17 21:57, Ken Javor wrote: Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits You are making too much of it. If the limit is in terms of dBuA/m, you use the loop magnetic field antenna factor, which is 51.5 dB less efficient than the loop electric field antenna factor. Of course, this is based on a far field assumption, and that is all you have available. But the magnetic field antenna factor is fundamental; it is the loop electric field antenna factor that is based on the FF assumption, so you need not worry at all. No worries! Ken Javor Phone: (256) 650-5261 *From: *"Kunde, Brian" *Reply-To: *"Kunde, Brian" *Date: *Thu, 17 Jan 2019 21:27:15 + *To: * *Conversation: *CISPR11 Rad Magnetic Field Emissions Limits *Subject: *[PSES] CISPR11 Rad Magnetic Field Emissions Limits Reference CISPR11/EN55011:2016 version. If you are an expert at the Radiated Emissions test from 150Khz -30Mhz for Class A Group 2 equipment, I could really use your help. I haven’t done this test in over 25 years. I refurbished our Active Loop antenna and placed it 10 meters from the EUT. I believe the data values read by our receiver is dBuV/m. However, the limits as it appears in Table 10 are in dBuA/m. How do I convert? I have an old 1999 copy of this standard that shows the limits with the exact same frequency ranges but the limits are in dBuV/m. Do I just use these limits or do I have to somehow convert the receiver data to dBuA/m. I know a straight conversion between dBuV/m and dBuA/m can be difficult because above 4Mhz we are in the far-field, but below that we are getting into the near field. And the impedance calculation can be difficult to obtain. Am I making too much of this or just take a simple conversion based on the differences between the two versions of the standard? Thanks for the help. The Other Brian *LECO Corporation Notice:**This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. *- 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 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> <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 Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - 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 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) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas mailto:sdoug...@ieee.org>> Mike Cantwell mailto:mcantw...@ieee.org>> For policy questions, send mail to: Jim Bacher mailto:j.bac...@ieee.org>> David Heald 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 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 graph
Re: [PSES] CISPR11 Rad Magnetic Field Emissions Limits
You are making too much of it. If the limit is in terms of dBuA/m, you use the loop magnetic field antenna factor, which is 51.5 dB less efficient than the loop electric field antenna factor. Of course, this is based on a far field assumption, and that is all you have available. But the magnetic field antenna factor is fundamental; it is the loop electric field antenna factor that is based on the FF assumption, so you need not worry at all. No worries! Ken Javor Phone: (256) 650-5261 From: "Kunde, Brian" Reply-To: "Kunde, Brian" Date: Thu, 17 Jan 2019 21:27:15 + To: Conversation: CISPR11 Rad Magnetic Field Emissions Limits Subject: [PSES] CISPR11 Rad Magnetic Field Emissions Limits Reference CISPR11/EN55011:2016 version. If you are an expert at the Radiated Emissions test from 150Khz -30Mhz for Class A Group 2 equipment, I could really use your help. I haven¹t done this test in over 25 years. I refurbished our Active Loop antenna and placed it 10 meters from the EUT. I believe the data values read by our receiver is dBuV/m. However, the limits as it appears in Table 10 are in dBuA/m. How do I convert? I have an old 1999 copy of this standard that shows the limits with the exact same frequency ranges but the limits are in dBuV/m. Do I just use these limits or do I have to somehow convert the receiver data to dBuA/m. I know a straight conversion between dBuV/m and dBuA/m can be difficult because above 4Mhz we are in the far-field, but below that we are getting into the near field. And the impedance calculation can be difficult to obtain. Am I making too much of this or just take a simple conversion based on the differences between the two versions of the standard? Thanks for the help. The Other Brian LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
[PSES] CISPR11 Rad Magnetic Field Emissions Limits
Reference CISPR11/EN55011:2016 version. If you are an expert at the Radiated Emissions test from 150Khz -30Mhz for Class A Group 2 equipment, I could really use your help. I haven't done this test in over 25 years. I refurbished our Active Loop antenna and placed it 10 meters from the EUT. I believe the data values read by our receiver is dBuV/m. However, the limits as it appears in Table 10 are in dBuA/m. How do I convert? I have an old 1999 copy of this standard that shows the limits with the exact same frequency ranges but the limits are in dBuV/m. Do I just use these limits or do I have to somehow convert the receiver data to dBuA/m. I know a straight conversion between dBuV/m and dBuA/m can be difficult because above 4Mhz we are in the far-field, but below that we are getting into the near field. And the impedance calculation can be difficult to obtain. Am I making too much of this or just take a simple conversion based on the differences between the two versions of the standard? Thanks for the help. The Other Brian LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
