| 摘要 |
<p>A pressure relief device for electrical equipment housing, includes a valve body having a pedestal that projects above a mounting flange and a table on the pedestal that supports a two-stage valve assembly that can be sized in diameter independently of the working area of the flange beneath the table. The design is particularly applicable to retrofit applications for large power distribution equipment with the footprint of the pressure relief device fixed by the design of the equipment housings. The first-stage valve opening can be sized substantially as large as vent openings in the housings and the second-stage valve openings can be sized in the desired relationship with the first-stage opening for optimizing valve performance independently of the constraints imposed by the footprint of the device.</p> |
