ISO 11452: Immunity Testing of Road Vehicle Components

ISO 11452 is a set of international standards and guidelines for the immunity testing of the electrical components found in commercial vehicles and passenger cars. ISO 11452 covers the testing of these components’ immunity to narrowband radiated electromagnetic energy without regard to the type of vehicle propulsion system. The sections of ISO 11452 are as follows:

• ISO 11452-1 | General principles & terminology
• ISO 11452-2 | Absorber-lined shielded enclosure
• ISO 11452-3 | Transverse electromagnetic (TEM) cell
• ISO 11452-4 | Harness excitation methods
• ISO 11452-5 | Stripline
• ISO 11452-7 | Direct radio frequency (RF) power injection
• ISO 11452-8 | Immunity to magnetic fields
• ISO 11452-9 | Portable transmitters
• ISO 11452-10 | Immunity to conducted disturbances in the extended audio frequency range
• ISO 11452-11 | Reverberation chamber

ISO 11452-2 is a vehicle component immunity standard that applies to the 200 MHz to 18 GHz range. This standard, like many automotive, military and aerospace standards, calls for moderately high fields to be generated. At frequencies below 200 MHz, antennas get physically larger and also less efficient. For frequencies below 200 MHz, the standard recommends the methods stated in parts 4, 3, and 5 of the ISO 11452 Severity Level Field I 25 V/m II 50 V/m III 75 V/m IV 100 V/m V (open to the users of the standard).

ISO 11452 recommends that these tests are performed in a shielded room. As is common with most immunity measurements, the intent of the test is to produce RF field levels which can be disruptive or damaging to the EUT; the shielded room removes the risk of unintended disruption to other sensitive devices or equipment outside of the test region. In the US, as in most other countries, there are limits on the radiation of energy without licenses, at frequencies that could affect licensed broadcasts.