Yes, it's important to recognize the limitations of a test method before
relying on it. In this case, the A-B method was used at power frequency and
below, to observe discharge time for UL testing. The MAIN advantage was not
balance so much as that the chassis was isolated from the potential being
Just to add to what Rich has stated - the CMRR will also vary with frequency
for both passive and active systems.
These variation are caused by small differences in the LCR coupling of the
probes and the finite bandwidth of any amplifier.
I remember using a very high gain product (A Thermal Ima
I read in !emc-pstc that cherryclo...@aol.com wrote (in <17c.18c06c2.296
20...@aol.com>) about 'EMC-related safety issues', on Mon, 31 Dec 2001:
>Quite a number of EMC and Safety experts took part in creating the IEE's
>Guide on EMC and Functional Safety, including a lawyer who specialis
I offered to forward this to the emc group for help.
Please answer directly.
- Robert -
Robert A. Macy, PEm...@california.com
408 286 3985 fx 408 297 9121
AJM International Electronics Consultants
619 North First St, San Jose, CA
In a court of law one must swear to tell the truth, the whole truth, and
nothing but the truth. What you stated below is merely part of the truth.
The rest of the truth is that spurious emissions emitted by unintentional
radiators (the kinds of emissions controlled by CISPR 22 and Title 47, part
Hi Cortland:
> One can also use a pair of probes known to be well balanced and take the
> difference between the A and B channels, or
> use a differential input accessory or plugin. There is then no possibility
> of high-voltage on the instrument chassis.
"Balance" is really Common-Mod
Dear Ken
Any electromagnetic emissions, whether conducted or radiated, including
spurious emissions (however you wish to define the word 'spurious') can be
demodulated by the non-linear processes in semiconductors, vacuum tubes, and
the like. So the spread of possible problems goes beyond merely
Dear John
Quite a number of EMC and Safety experts took part in creating the IEE's
Guide on EMC and Functional Safety, including a lawyer who specialises in
high-tech issues. You will find their names listed at the end of the 'core'
of the guide (downloadable from www.iee.org.uk/Policy/Areas/Ele
Hi Xing Weibing:
> 2. supply the SMPS from an isolating transformer where
> both supply conductors are isolated from ground.
> 3. connect secondary's ground and primary 's ground (neutral and ground
> are connected together)
This is the correct connection for measuring the
prim
I read in !emc-pstc that cherryclo...@aol.com wrote (in <123.96b6ec6.296
1b...@aol.com>) about 'EMC-related safety issues', on Mon, 31 Dec 2001:
>(A key member of the IEC 61000-1-2 committee is a very senior safety
> expert
>and also a key member of the IEE Working Group that created thi
All of this message is very interesting and I have no problem with it at
all. That doesn't change the fact that, as I and others stated earlier,
there is no intrinsic safety issue with a spurious emission. Spurious
emissions only affect the ability to receive a radio signal. That was and
is the
Dear all
There was a discussion about electromagnetic emissions and safety issues a
couple of weeks ago which I only caught the tail end of, so I hope my
comments below are relevant and useful.
I would also like to make a plea for assistance.
Spurious emissions and safety.
Even if we ignore 'le
12 matches
Mail list logo
