The limits in this standard are designed to provide protection for broadcast receivers in the frequency range of 30 MHz to 1 000 MHz when used in the residential environment. Compliance with this standard may not provide adequate protection for new types of radio transmissions or receivers used in the residential environment nearer than 10 m to the vehicle, boat or device.
Note 1: Experience has shown that compliance with this standard may provide satisfactory protection for receivers of other types of transmissions when used in the residential environment, including radio transmissions in frequency ranges other than that specified.
This standard applies to the emission of electromagnetic energy which may cause interference to radio reception and which is emitted from
The emission sources are:
a) Vehicles propelled by an internal combustion engine, electrical means or both (see 3.1);
b) Boats propelled by an internal combustion engine, electrical means or both (see 3.2). Boats are to be tested in the same manner as vehicles except where they have unique characteristics as explicitly stated in this standard;
c) Devices equipped with internal combustion engines (see 3.3).
This standard includes the limit and methods of measurements of the peak and quasi-peak detector and average detector.
This standard does not apply to aircraft, traction systems (railway, tramway and electric trolley bus), or to incomplete vehicles.
Note 2: Protection of receivers used on board the same vehicle as the disturbance source(s) are covered by GB 18655.
The measurement of electromagnetic disturbances while the vehicle is connected to power mains for charging is not covered in this standard. The user is referred to appropriate IEC and CISPR standards which define measurement techniques and limits for this condition.
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments to (excluding amending error in the text), or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest edition of these documents is applicable. For undated references, the latest edition of the normative document is applicable to this standard.
GB/T 4365 Electrotechnical Terminology-Electromagnetic Compatibility (GB/T 4365-2003, IEC 60050 (161):1990, IDT)
GB/T 6113.1-1995 Specifications for Radio Disturbance and Immunity Measuring Apparatus
GB 18655 Limits and Methods of Measurement of Radio Disturbance Characteristics for the Protection of Receivers Used on Board Vehicles(GB 18655-2002, idt CISPR 25:1995)
3 Terms and Definitions
For the purpose of this document, the terms and definitions contained in GB/T 4365 as well as the following apply.
3.1
Vehic1e
It refers to the machine operating on land which is intended to carry persons or goods. Vehicles include, but are not limited to, cars, trucks, buses, mopeds, agricultural machinery, earth-moving machinery, material-handling equipment, mining equipment and snowmobiles.
3.2.
Boat
It refers to the vessel intended to be used on the surface of water, its length being no greater than 15 m.
3.3
Device
It refers to the machine driven by an internal combustion engine which is not primarily intended to carry persons or goods. Devices include, but are not limited to, chainsaws, irrigation pumps, snow blowers, air compressors, and landscaping equipment.
3.4
Impulsive ignition noise
It refers to the unwanted emission of electromagnetic energy, predominantly impulsive in content, arising from the ignition system within a vehicle, boat or device.
3.5
Ignition noise suppressor
It refers to that portion of a high-voltage ignition circuit intended to limit the emission of impulsive ignition noise.
3.6
Resistive distributor brush
It refers to the resistive pick-up brush in an ignition distributor cap.
3.7
Frequency sub-band
It refers to the segment of the frequency spectrum (30 MHz to 1 000 MHz) defined to enable statistical evaluation of the test data acquired by swept frequency testing.
3.8
Representative frequency
It refers to the assigned frequency of a frequency sub-band to be used for comparison of the data to the limit (only used to 6.4 and 6.5 and Annex A).
3.9
Characteristic level
It refers to the controlling (or dominant) emission level experienced in each frequency sub-band. The characteristic level is the maximum measurement obtained for both antenna polarizations and for all the specified measurement positions of the vehicle, boat or device. Known ambient signals are not considered part of the characteristic level.
3.10
Tracking generator
It refers to the test signal oscillator (continuous wave, cw) that is frequency locked to the receive frequency of a measuring instrument.
3.11
RF disturbance power
It refers to RF power measured with a current transformer of an absorbing clamp and an RF measuring instrument. It may be measured C as the RF disturbance voltage C in a peak or quasi-pea mode.
3.12
Spark discharge
In this document, it refers to the discharge of energy stored in the ignition coil, in an arc across the electrodes of a measuring spark-plug.
3.13
Resistive high-tension (HT) ignition cab1e
It refers to the ignition cable whose conductor has a high resistance (attenuation).
3.14
Residential environment
It refers to the environment having a 10 m protection distance between the source and the point of radio reception and where the source uses the public low voltage power system or battery power. Examples of a residential environment include rooming houses, private dwellings, entertainment halls, theatres, schools, public streets, etc
4 Limits of Disturbance
4.1 Determination of Conformance of Vehicle/Boat/Device with Limits
Figure 1 defines the method for determination of conformance.
