IEC 61000-5-7:2001 pdf download

IEC 61000-5-7:2001 pdf download.Electromagnetic compatibility (EMC) –
Part 5-7: Installation and mitigation guidelines – Degrees of protection provided by enclosures against electromagnetic disturbances (EM code).
2 Normative references
The following normative documents contain provisions which, through reference in this text. constitute provisions of this part of IEC 61000. For dated references, subsequent amendments to. or revisions of, any of these publications do not apply However, parties to agreements based on this part of IEC 61000 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies Members of ISO and IEC maintain registers of currently valid International Standards.
IEC 60050(161): International Electrotechnical Vocabulary (1EV) — Chapter 161: Electromagnetic compatibility
IEC 60050(826): International Ei’ecfrotechnical Vocabulary (1EV) — Chapter 826: Electrical installations of buildings
IEC 60068-1: Environmental testing — Part 1: General and guidance IEC 60529: Degrees of protection provided by enclosures (IP Code)
IEC 61000-4-3: Electromagnetic compatibility (EMC) — Part 4: Testing and measurement techniques — Section 3: Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-23: Electromagnetic compatibility (EMC) — Part 4-23: Testing and measurement techniques — Test methods for protective devices for HEMP and other radiated disturbances
3 General
Other standards in the IEC series define requirements for construction and immunity testing of electrical and electronic equipment which shall withstand the stresses produced by electromagnetic disturbances, including fast electrical transients and electrostatic discharge (ESD). In addition, there are similar requirements for testing to verify immunity to high-altitude electromagnetic pulses (HEMP). There are also existing standards for these enclosures for other effects, primarily IEC 60529
However, manufacturers of this electrical and electronic equipment need to either construct or procure enclosures for this equipment prior to the electromagnetic disturbance immunity testing noted in the previous paragraph With experience the manufacturers will be able to determine the particular levels of electromagnetic shielding effectiveness which are sufficient to permit their finished product to pass the required EMC immunity and emissions tesis.
Shielding Effectiveness (SE) is a broad term describing the ability of an EM shield to reduce or attenuate external (or Internally produced) electromagnetic fields and external (or internal) surface currents before they reach the interior (exterior) of the shield. Typically, the shield encloses sensitive electronic equipment that must be protected from exterior electromagnetic disturbances, However, shields are also used to reduce electromagnetic fields produced by interior equipment from reaching the exterior of the shield. EM protection is provided by a complete topology, consisting not only of a metallic shell surrounding the shielded volume, but also including proper trealments of required electrical (power, communication, antenna, signal,
alarms, etc.) and mechanical penetrations (doors, vents, pipes, etc.). Testing of non-linear
terminal protection devices for electrical penetrations is beyond the scope of this standard and
is addressed in other IEC standards. Equipment manufacturers should coordinate the
protection provided by electromagnetic shields and line penetration protection devices such as
filters and non-linear elements to afford comparable levels of protection against both radiating
electromagnetic fields and conducted transients.
Enclosure shielding effectiveness is defined as the ratio of received power with and without an
intervening shield system inserted between a receiving and a transmitting antenna. The
shielding effectiveness at a given point thus requires a calibration sweep (no barrier) and a
measurement sweep (with barrier), and is obtained as the power ratio (difference in dB)
between these two separate results. Assuming that sensor antenna voltage is detected, then,In addition, for each shielding effectiveness result, a measurement range (MR) must be given
which quantifies the noise floor for the measurements. The measurement range defines the
maximum shielding effectiveness that can be accurately measured. For empty equipment
enclosures, the measurement range is obtained in the same manner as the shielding
effectiveness from the same calibration sweep and an additional noise sweep, which is a
measurement with the external energy radiated by the shielding efflectiveness diagnostic
equipment but with the cable to the receive antenna terminated in 50。(at the same location
as the antenna).