Reverberation Chamber – A Novelty in Automotive Component EMC Testing

For several years, SIQ has been EMC testing automotive components for domestic and foreign customers. Requirements for EMC testing are principally laid down in numerous ISO, CISPR, and EN standards.

Furthermore, automotive manufacturers set their specific technical requirements which, as a rule, are much stricter than those of the mentioned standards. By continuously updating them, automotive manufacturers keep strengthening the requirements for compatibility or reliability of their products.

When reviewing newly published technical requirements in the first half of 2019, we noticed that the PSA group of automotive manufacturers (Peugeot, Citroën, Opel, etc.) had published new B21 7110 requirements for component EMC testing. Those included, as a novelty, a requirement for EM field immunity testing in a reverberation chamber. A reverberation chamber is an electromagnetic shielded room with a minimum absorption of electromagnetic energy. Due to low absorption, very high field strength can be achieved with moderate input power.

With no delay, we performed a comprehensive feasibility study to determine the possibilities for such testing and the potentials to build such a chamber at SIQ premises. The study showed that the optimal solution would be to change our electromagnetic shielded room into a chamber with the additional function of a reverberation chamber.

At the beginning of 2020, we started collecting offers and selecting service providers. COMTEST—a Dutch company—supplied the equipment necessary to build the chamber; R&S—a company from Germany—supplied electronic equipment and software. The implementation works and calibration of electromagnetic field homogeneity were entrusted to the Slovene company S-TMM Sistemi, the main contractor.

In the remodelled chamber, we can test according to ISO 11452-11 and EN 61000-4-21 standards. The first one lays down requirements for electric and electronic automotive component testing in a reverberation chamber, while the second one sets requirements for testing other electric and electronic components in a reverberation chamber. The electromagnetic field that we generate in the frequency range from 80MHz to 6GHz can be measured in kV. The fields of such amplitudes are used also for the testing of various electric and electronic military components. The MIL-STD-461 standard that addresses such products also lays down requirements for electromagnetic immunity testing in a reverberation chamber.

The works on the chamber were finished at the end of September. At the time, we already had the first order for component testing according to the PSA B21 7110 technical requirements.

In the reverberation chamber, we can test according to ISO 11452-11 and EN 61000-4-21 standards for electric and electronic automotive component testing and other electric and electronic component testing.

Author: Marjan Mak, +386 1 4778 178, marjan.mak@siq.si