CISPR11 RF Disturbance Power EMI RFP Radiation Emission EMC Test Systems

Standards & Clauses:

CISPR11 / GB4824: Industrial, scientific and medical (ISM) radio-frequency equipment and similar equipment –Radio-frequency disturbance characteristics –Limits and methods of measurement
CISPR13 / GB13837: Sound and television broadcast receivers and associated equipment –Radio disturbance characteristics –Limits and methods of measurement
CISPR14-1 / GB4343.1: Electromagnetic compatibility. Requirements for household appliances, electric tools and similar apparatus -Part 1: Emission

Samples and Restrictions:

Industrial, scientific and medical (ISM) radio-frequency equipment; sound and television broadcast receivers and associated equipment; household appliances, electric tools; etc.

Application:

Absorption clamp measurement (ACMM) is an alternative to the method of measurement of radiation emission for small test objects, such as household appliances and power tools, where only one power lead is connected. ACMM with absorbing clamp to determine the disturbance power. The advantages of ACMM's radiated emission measurements are the reduction of testing time and cost savings.

Test Principle:

The principle is that for a small EUT, the radiation emitted by the common-mode current on the lead is much larger than the outward radiation on the surface of the test object. The power cord of the EUT can be considered as a radiating antenna where the disturbance power is approximately equal to the power at the measured EUT provided to the test line (LUT) at the position where the clamp is at the common mode current maximum. In order to find "common-mode current maxi- mum," the absorption forceps need to be able to move, so an absorber clamp rail length of 6 meters is required in the test system.

Structure:

Main test equipment: receiver, power absorption clamp, decoupling clamp, slide, EMC test software
Test environment: shielded room (length greater than 8m)

Use Environment​:

Power supply: 380V ± 10%, 50 / 60Hz
Ambient temperature: 5 °C ~ +40 °C, there should be no high concentration of dust, corrosive gas, flammable and explosive objects

Technical Parameters:

Main Test Equipment	receiver, power absorption clamp, decoupling clamp, slide, EMC test software, etc.
Test Environment	Shielded room (length greater than 8m)
Frequency Range	The frequency range specified by the general standards is 30MHz - 300MHz, and the frequency range required for audio and video equipment is 30MHz-1GHz.
Schematic Diagram