BS ISO 7637-3:2007 - Page 2

Road vehicles. Electrical disturbances from conduction and coupling. Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines | Status: Revised, Superseded, Withdrawn

1 Scope This part of ISO 7637 establishes a bench top test for the evaluation of the immunity of devices under test (DUTs) to transient transmission by coupling via lines other than supply lines. The test transient pulses simulate both fast and slow transient disturbances, such as those caused by the switching of inductive loads and relay contact bounce. Three test methods are described in this part of ISO 7637:

• — the capacitive coupling clamp (CCC) method;
• — the direct capacitive coupling (DCC) method; and
• — the inductive coupling clamp (ICC) method.

NOTE The applicability of the three test methods is shown in Table 1.

Only one test method need be selected for slow transients and only one method need be selected for fast transients. This part of ISO 7637 applies to road vehicles fitted with nominal 12 V, 24 V or 42 V electrical systems. For transient immunity, Annex B provides recommended test severity levels in line with the functional performance status classification (FPSC) principle described in ISO 7637-1.