Less Work to Meet Safety Requirements
Peter Walsh, PE
Some facilities are changing their requirements for motor and appliance installations. This could be due to OSHA Lock-out and Tag-out requirements or NFPA 70E. The change is toward using pin and sleeve devices instead of having a hard-wired installation.
Safety requirements often have the maintenance person checking for the absence of voltage before touching. The rules are quite specific and are enforced by OSHA. When electrical equipment is fed only by a cord and plug, most safety requirements are relaxed. The device just has to be unplugged.
Getting to the unplugged condition has to follow other requirements. The typical pin and sleeve plug is not supposed to be opened under load. How can you be sure it’s not under load? Use a disconnect to supply the receptacle.
When an electrical contractor is asked to install a safety switch feeding a plug and sleeve receptacle, the total installation cost is less with a combination mechanically interlocked receptacle. It is one unit to install, instead of two.
The Legrand IEC 309 mechanically interlocked receptacle provides safety and time-saving features. It’s a one-piece unit that meets strict company safety programs. The components are prepared for rapid installation, such as fast threads, pre-wired switch, and onion peel bushing adapting to various wire diameters.
These fusible units have additional safety features. They have integral fuse holders and LED indicators that protect critical equipment. The mechanical interlock prevents unplugging the circuit without turning the switch off first. The range is 30, 60 and 100 amperes, covering up to 50 horsepower at 480 volts.
Safety requirements often have the maintenance person checking for the absence of voltage before touching. The rules are quite specific and are enforced by OSHA. When electrical equipment is fed only by a cord and plug, most safety requirements are relaxed. The device just has to be unplugged.
Getting to the unplugged condition has to follow other requirements. The typical pin and sleeve plug is not supposed to be opened under load. How can you be sure it’s not under load? Use a disconnect to supply the receptacle.
When an electrical contractor is asked to install a safety switch feeding a plug and sleeve receptacle, the total installation cost is less with a combination mechanically interlocked receptacle. It is one unit to install, instead of two.
The Legrand IEC 309 mechanically interlocked receptacle provides safety and time-saving features. It’s a one-piece unit that meets strict company safety programs. The components are prepared for rapid installation, such as fast threads, pre-wired switch, and onion peel bushing adapting to various wire diameters.
These fusible units have additional safety features. They have integral fuse holders and LED indicators that protect critical equipment. The mechanical interlock prevents unplugging the circuit without turning the switch off first. The range is 30, 60 and 100 amperes, covering up to 50 horsepower at 480 volts.
Photo courtesy of Legrand/Pass & Seymour
