Cable networks for television signals, sound signals and interactive services – Part 2: Electromagnetic compatibility for equipment
|Publication Date:||1 January 2010|
|ICS Code (Electromagnetic compatibility (EMC)):||33.100|
|ICS Code (Cabled distribution systems):||33.060.40|
This part of IEC 60728 applies to the radiation characteristics and immunity to electromagnetic disturbance of EM-active equipment (active and passive equipment) for the reception, processing and distribution of television, sound and interactive multimedia signals as dealt with in the following parts of the IEC 60728 series:
- IEC 60728-3 Active wideband equipment for coaxial cable networks
- IEC 60728-4 Passive wideband equipment for coaxial cable networks
- IEC 60728-5 Headend equipment
- IEC 60728-6 Optical equipment
It covers the following frequency ranges:
- Disturbance voltage injected into the mains 9 kHz to 30 MHz
- Radiation from active equipment 5 MHz to 25 GHz
- Immunity of active equipment 150 kHz to 25 GHz
- Screening effectiveness of passive equipment 5 MHz to 3 GHz (25 GHz)2
This standard specifies requirements for maximum allowed radiation, minimum immunity and minimum screening effectiveness and describes test methods for conformance testing.
Due to the fact that cable networks, the former cabled distribution systems for television and sound signals, are more and more used for interactive services, these networks may incorporate also equipment, which carry besides the cable network equipment ports also one or more telecom signal port(s) as well as one Ethernet (IP) port. This equipment should be named as multimedia network equipment.
The EMC behaviour of cable network equipment, telecommunication network equipment and multimedia network equipment may be described by the following port structure (see Table 1).
The electromagnetic compatibility requirements for telecommunication network equipment only are standardized in EN 300 386 (mainly) and in EN 301 489-4, those for cable network equipment only are given in this IEC 60728-2.
Equipment for multimedia networks of the above mentioned type has to work under the same EMC conditions as equipment, which is falling under the cable network and the telecommunication network EMC-standards. Due to the fact, that this equipment has to work in close proximity, e.g. in the same operating room, the EMC environmental conditions for all three types of equipment are the same.
This means that multimedia network equipment has to fulfil the EMC requirements of one of the above mentioned standards and in addition the EMC requirements, laid down in the other EMC standard, for the additional port, by which it is connected to the other network.
By this procedure it is ensured that multimedia network equipment fulfils the EMC conditions of one of the above mentioned networks and will neither disturb the respective other system nor will be disturbed by the respective other system via the connecting port.
Coaxial cables for cable networks do not fall under the scope of this standard. Reference is made to the European Standard series EN 50117.
This standard also covers active indoor antennas for which the requirements and the applicable methods of measurement are limited to the radiation and the electrostatic discharge phenomena.
Standardisation in the field of electromagnetic compatibility for any broadcast terminals (e.g. tuners, receivers, decoders, etc.) is covered by the International Standards CISPR 13 and CISPR 20 and for multimedia terminals by CISPR 22 and CISPR 24.
Requirements for the electromagnetic compatibility of receiver leads are laid down in IEC 60966-2-4, IEC 60966-2-5 and IEC 60966-2-6.
2 For screening effectiveness of passive equipment no requirements apply at present for the frequency range 3 GHz to 25 GHz. Methods of measurement and limits are investigated for inclusion in a future amendment or revised edition.