Measuring Interference On Power Lines And Signal Lines With A Current Detection Probe - Saluki SER Series User Manual

EMI Receiver Instructions for Use
Due to the many measurement errors caused by near-field measurement, how to equate the near-field measurement data to the far-field
There is no ready-made theoretical calculation formula. Because the size of the shielded darkroom is different, the electromagnetic wave reflection is different,
The test distance is different, so it is difficult to derive a theoretical calculation formula for the equivalent far and near field. However, there are conditions
Some units can conduct actual measurements according to the specific conditions of their own laboratories to find out a rule. In general, near
The electromagnetic field strength measured in the far field is much stronger than that measured in the far field, and it increases with frequency
The difference also decreases linearly. In this way, it can be pre-estimated whether the device under test can pass the military standard requirements.
4.2 Current Sense Probes and Current Injection Probes
Most of the interference signals are related to the presence of interference currents in wires and cables, which can wait for
The effect is a loop antenna and a dipole antenna, which can both transmit and receive signals. In EMC measurements,
Measuring the performance of the transmitted signal on the cable of the equipment is called conducted emission measurement; applying a certain intensity to the cable of the equipment
To assess the anti-interference ability of the equipment with a high-degree signal is called conduction sensitivity measurement. Whether measuring interference on the cable
Whether to inject disturbances into the cable, a coupling device is required, which is usually called a current probe (or
called a current caliper). Current probes can be classified into current sense probes and current injection probes. Current sense probe
Used to measure conducted emissions, to measure interference on conductors and cables; current injection probes are used to measure conducted susceptibility
Quantity, that is, the technology of injecting strong interference signals into the cable, referred to as BCI (Buik Current
Injection). When using a current probe, the probe does not touch the wire, and generally does not change the normal state of the circuit under test.
State of working or normal arrangement.
4.2.1. Measuring interference on power and signal lines with a current detection probe
Connect the current detection probe to the input terminal of the spectrum analyzer, and snap the current detection probe to the power line under test,
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