Fischer Custom Comm. F-201-23mm
The absorbing clamp method of measurement is accepted by CISPR as a standard method of measuring the interference power levels on cables connected to electronic devices. Measurement can be made from 30 MHz to 1 GHz.
The absorbing clamp consists of a ferrite current transformer calibrated for the frequency range of 30 MHz to 1 GHz and two groups of ferrite rings. The ferrite rings act as absorbers of energy and impedance stabilizers. One group of ferrite rings surrounds the lead from the current transformer to the measuring device to minimize standing waves. The second group of ferrite rings surround the mains lead connected to the apparatus under test. These rings act as an impedance stabilizing the power mains and as an absorber of energy to isolate the device under test from the mains. The mains lead to the apparatus under test is easily placed inside the aperture of the rings since the rings can be opened and closed.
The current transformer is placed around the mains lead, and provides a voltage proportional to the resultant current in the leads.