See below.
Jon D. Curtis, PE
Curtis-Straus LLC j...@world.std.com
One-Stop Laboratory for EMC, Product Safety and Telecom
527 Great Road voice (508) 486-8880
Littleton, MA 01460 fax (508) 486-8828
http://world.std.com/~csweb
On Thu, 30 Jan 1997, Terry J. Meck wrote:
> Hello all:
>
> What can you tell me about these specs.?
>
> IEEE-C62.41-1991 SURGE voltages in Low-Voltage AC Power Circuits *
Successor to IEEE 587. Describes the surge environment. Models surges as
two primary waveshape types. The unidirectional 1.2x50uS/8x20uS wave and
the 100kHz ring wave. Says surges can reach 6kV (at that point the
outlets arc over). Divides the enviroment into three catagories: C:
outside, B: near the service entrance, A: deeper inside buidings. Says
surges can reach 6kV at both A and B, but current limits A to 200A peak on
the ring wave. Unidirectional surge not applied to environment A.
Note that EN61000-4-5/IEC1000-4-5 adopted the unidirectional wave and
applies it at lower voltages through slightly different impedances.
The standard also identifies three other waveshapes which can be seen in
nature and which may be appropriate for specific products. These include
a long duration surge, Electrical fast transient bursts, and a slow ring
wave.
This standard does not set limits. It is a measurement technique standard
with emphasis on the description of the environment based on decades of
technical studies.
> >
IEEE STD 142-1991 Grounding of Industrial and Commercial Power >
> IEEE STD 519-1992 Harmonic Control in Electric Power Sys. *
>
> IEEE STD 587-1980 electrical noise immunity spec. *
The granddaddy of modern surge standards. Superceeded by 62.41 and
1000-4-5.
>
> Are there specified testing procedures to these * marked standards?
The two I have written about ARE test proceedures. In order to apply them
you need a specification of the surges levels to be applied along with a
performance criteria.
>
> Are there EN or IEC standards that correlate to these standards?
EN61000-4-5 is the direct decendent of these standards.
>
> With reference to noise pulses how does
> IEEE-C62.41-1991 or IEEE STD 587-1980 apply the
> following? To what environment or connect category?
> That is to say, these wouldn't be applied to single
> phase equipment @ 5A would they?
Sure. But probably not at the maximum level specified in the standard.
There is a neat chart in C62.41 which illustrates the number of surges
in a given year at a given level which can be expected. Turns out 1kV
surges are quite common. Especially if you live in Florida or Long
Island where there is lots of lightning.
>
> High impedance 6KV amplitude with a 1.2 sec rise time and a 50 sec
> duration.
>
> Low impedance 3KA amplitude with an 8 sec rise time and 20 sec
> duration 80 joules energy.
>
> High impedance 6KV amplitude with a .6 sec duration at 100KHZ
>
>
> Low impedance 500A amplitude with an .6 sec duration at 100KHZ (4
> joules energy).
>
>
> For example the proposed specs of EN 61000-4-5 for an
> industrial environment (50082-2:1995) indicate 4kVCM
> and 2kV DM 1,2/50 (8/20) Tr/Th sec.
>
> Another question. As long as I am bringing up EN
> 61000-4-5 for an industrial environment. Would it be
> acceptable to specify a CE compliant external surge
> suppressor for a piece of CE marked equipment that
> would provide compliance to the standard when
> used/required in the installation. This would move
> the environment criteria would it not?
You are allowed to specify the performance criteria for your equipment.
If you want to tell your user in the manual that you require an external
surge suppressor to be surge immune then that's OK. In effect you are
telling them that if they choose not to use such a surge suppressor that
the unit's performance under surge conditions is unpredictable.
>
> Thanks for your comments in advance.
>
>
> Best regards,
> Terry J. Meck
> Senior QA/Test Engineer
> 215-721-5280
> tjm...@accusort.com
> Accu-Sort Systems Inc. Telford, Pa USA
>
