| 摘要 |
<p>The housing has internal partition walls (3) each with apertures for passage of contact elements, current cables or current rails. The partition walls (3) have two parallel plates (4,5) with an air gap between them having a width of between 8 and 25mm. The two plates (4,5) are pref. of sheet metal e.g. sheet steel. If an arc occurs on one side of the wall (3) it subjects a region (6) of one plate (4) to a thermal load with a subsequent rupture point (7) occurring. Air then flows from the gap between the plates (4,5) through the rupture point (7) to provide arc quenching and ensuring that the arc is not transmitted across the partition wall (3). The housing provides a high degree of safety for adjacent appts. and personnel and is simple and economical.</p> |
