ISO 11452-4 Turn Key Solution for Harness Excitation Methods (BCI and TWC)

ISO 11452-4 Overview

ISO 11452 specifies harness excitation test methods and procedures for determining the immunity of electronic components of passenger cars and commercial vehicles regardless of the propulsion system (e.g. spark-ignition engine, diesel engine, electric motor).

The bulk current injection (BCI) test method is based on current injection into the wiring harness using a current probe as a transformer where the harness forms the secondary winding.

The tubular wave coupler (TWC) test method is based on a wave coupling into the wiring harness using the directional coupler principle. The TWC test method was developed for immunity testing of automotive components with respect to radiated disturbances in the GHz ranges (GSM bands, UMTS, ISM 2,4 GHz). It is best suited to small (with respect to wavelength) and shielded device under test (DUT), since in these cases the dominating coupling mechanism is via the harness. For DUTs which are larger than a wavelength (e.g. 0,1 m at 3 GHz), direct field coupling to the printed circuit board (PCB) becomes of equal importance. The user of the TWC test method should take this into account and determine the applicability of the method. The electromagnetic disturbances considered in this part of ISO 11452 are limited to continuous narrowband electromagnetic fields.

Turn Key Solution for ISO 11452-4 Includes:

The EMC Shop can provide a variety of combinations from our trusted manufactures to satisfy 11452-4 testing specifications. Equipment combinations include but not limited to the following:

• of the BCI test method is 1 MHz to 400 MHz
• of the TWC test method is 400 MHz to 3 GHz

BCI test method

BCI is a method of carrying out immunity tests by inducing disturbance signals directly into the wiring harness by means of a current injection probe. The injection probe is a current transformer through which the wiring harnesses of the device under test (DUT) are passed. Immunity tests are carried out by varying the test severity level and frequency of the induced disturbance.

The following equipment is used:
— ground plane;
— current injection probe(s);
— current measurement probe(s);
— artificial network(s) [AN(s)];
— radio frequency (RF) generator with internal or external modulation capability;
— power amplifier;
— power measuring instrumentation to measure the forward and reverse power;
— current measurement equipment.

TWC test method

The approach of this test method is an equivalent coupling to a plane wave coupling into a wiring harness of automotive components. To realize this, a short 50 Ω coaxial line configuration with open ends, an inner tubeshaped conductor and matched terminations are used to generate a transverse electromagnetic (TEM) wave inside. The wiring harness leads through the inner conductor of the wave coupler. This leads to two disturbing components for the DUT: a TEM wave component coupled via the cable, and a radiated component, caused by the scattering field from the primary TEM wave in the connecting cable between the coupler and the DUT.

The following equipment is used:
— ground plane;
— tubular wave coupler;
— artificial networks(s) [AN(s)];
— RF generator with internal or external modulation capability;
— power amplifier;
— power measuring instrumentation to measure the forward and reverse power.