Non Fused Disconnect Clearance

The disconnect is a non fuse puller type and is ul listed with an enclosed pull out switch.

Non fused disconnect clearance. There are two types of disconnect switches commonly used in commercial businesses. When dangerous fluctuations or interruptions are detected your disconnect will as you may expect disconnect power to the tool shutting off access safely before permanent harm or danger can arise. So the only two places for non fused disconnects are on systems with less than 5ka available fault current or on circuits already protected by appropriately sized fuses. Are you protecting yourself from electric shock and burns.

And 3 minimum headroom. Does this requirement extend to non. A 3000a service entrance fuse won t protect the non fused disconnect it needs to a fuse of a size that would go in the disconnect if it were fused. 2 a 30 in wide working space in front of equipment operating at 600v or less.

A non fused disconnect generally has a short circuit withstand of 5000a and a fused disconnect very often has the withstand rating of the fuse that is inserted and approved by the manufacturer resulting in almost always 200k. A fused disconnect will also help with certain downstream withstand ratings such as for some transfer switches etc. 110 26 of the national electrical code nec. 1 at least a 3 ft clearance in front of all electrical equipment.

Nec 110 26 requires working clearance in front of equipment likely to require calibration testing or adjustment while energized. You re not if you fail to comply with the following three clearance requirements in sec.