| 摘要 |
<p>The circuit board has plates (12, 13) comprising strip guards (18) that are electric-conductively connected to outer side (17). A backup strip guard (25) comprises a backup portion (26) with reduced cross-section, and is arranged in an intermediate layer (14) between the secured plates. An extinguishing volume (27) is formed adjacent to edge of the intermediate layer and edges of the plates. Breakdown spacing is predetermined between the backup portion and the extinguishing volume. The breakdown spacing is smaller than distance between the strip guards in the intermediate layer.</p> |
