Question: what is the difference between nema 3 and 4?
Answer: NEMA 3: For indoor or outdoor use. Same as NEMA 2 but adds stronger protection against the ingress of water and dust. It protects against windblown dust, rain, sleet, and snow and will be undamaged by ice forming on the enclosure. ... NEMA 4: Same as NEMA 3 but adds protection against hose directed water.