From RE to CE: How Solidot Uses a Self‑Built Anechoic Chamber for Independent I/O Module EMC Verification

Electromagnetic interference on industrial sites constantly tests the "ruggedness" of every field device. How to make "reliability" more than just a specification sheet claim? Solidot's answer is: keep verification capabilities in-house. Relying on its self‑built 3‑meter semi‑anechoic chamber, Solidot has achieved independent EMC verification for its products, covering three core tests: RE (Radiated Emission), RS (Radiated Susceptibility), and CE (Conducted Emission). Among these, RE and CE are emission tests to ensure the product's external electromagnetic interference stays within limits, while RS is an immunity test to verify stable operation under external electromagnetic interference.

How are these tests conducted? Below are the actual procedures for RE, RS, and CE, with examples:

RE Radiated Emission Test
RE (Radiated Emission) test: The I/O module is placed on a turntable that rotates 360°. A log‑periodic antenna is mounted on a pneumatic antenna tower at a distance of exactly 3 meters from the module – which is the origin of the "3‑meter method" name.
During the test, the antenna moves up and down within a range of 1 to 4 meters, switching between horizontal and vertical polarization to capture the module's maximum radiation in all directions. Signals are transmitted via RF cables to the control room, analyzed by the receiver, and displayed on the computer. This means every trace of electromagnetic noise radiated by the module is quantified, and any exceedance is immediately exposed.

RS Radiated Susceptibility Test
RS (Radiated Susceptibility) test: Similarly, the I/O module is placed on the turntable. A stacked log‑periodic antenna is positioned 3 meters from the module. A signal generator outputs a swept‑frequency signal, amplified by a power amplifier to drive the antenna, creating a uniform interference field at the module's location.
During the test, the module's operating status is uploaded to the PLC via a coupler, and the computer reads PLC data in real time. Combined with monitoring camera footage, the module's operation is displayed synchronously in the control room. The module must maintain uninterrupted communication and error‑free data under continuous interference – a hardcore simulation of "harsh conditions" on industrial sites.

CE Conducted Emission Test
The CE (Conducted Emission) test is conducted in the control room. The I/O module is placed on a table. The Line Impedance Stabilization Network (LISN) supplies clean power to the module while simultaneously receiving interference signals generated by the module and transmitting them to the receiver for analysis, with final results displayed on the computer.

For users, the self‑built chamber brings far more than testing convenience: verification cycles are no longer constrained by external lab scheduling; after parameter adjustments, re‑testing can be done on the same day. Products undergo more thorough and intensive verification iterations before mass production – every I/O module delivered to the field has been "tempered" in this chamber before leaving the factory.
After future CNAS accreditation, the test data issued by the laboratory will carry third‑party authority, providing stronger support for compliant product delivery. For Solidot, reliability is not just a slogan – it is a verifiable system.