What is the purpose of the NEMA 3R enclosure rating?
The National Electrical Manufacturers Association sets the NEMA 3R enclosure rating to protect against falling rain, sleet, snow and external ice formation. These enclosures also protect against the ingress of solid foreign objects like dust.
What is the difference between fusible and non-fusible switches?
Fusible switches have in-built fuses designed to melt and break the circuit in the event of a fault or overload. In non-fusible switches, the fuse is absent and they rely on other protective devices like circuit breakers or fuses located upstream to interrupt the circuit in case of a fault or overload.