NEMA 4 适用于户外电器外壳s,并且具有此等级的外壳必须由能够承受室外紫外线水平而不会降解的材料制成。NEMA 4 的测试包括用 65 英寸喷嘴软管从不小于 1 英尺的距离向外壳喷洒至少 10 GPM 的水,持续 5 分钟。没有水可以渗透到盒子里。NEMA 4 评级系统中有一个子组,即 NEMA 4x。这与 NEMA 3x 评...
NEMA ratings, widely used in the United States, are based on the NEMA 250 standard “Enclosures for Electrical Equipment (1000 Volts Maximum).” They indicate the level of protection a device has, ranging from falling dust to corrosive media. All NEMA ratings assume that the enclosure protects ...