All Aircraft…Be Safe With Electrical SystemsPosted: 2014/08/12
Mechanics, when working on electrical systems, Always make sure circuit breakers are in the OFF (pulled) position. If they must be locked or deactivated, follow the procedures in Para 65. b. 1 of WP 028 00 in TM 1-1500-323-24-1, Installation and Repair Practices Aircraft Electric and Electronic Wiring.
During aircraft ground operations, there are times when positive lockout deactivation of circuit breakers will be required to prevent damage to the aircraft and yourself. Unfortunately, it’s not happening. And that’s almost always because mechanics say they don’t have the equipment to lock circuit breakers.
Circuit breakers must have a lockout ring, collar or safety lockout sleeve installed on the circuit breaker anytime you work on electrical systems. If you don’t have any of these items, order them now. Don’t work on aircraft electrical systems until you get them.
The TM lists the part numbers for the lockout sleeves and kits you’ll need but not the NSNs. Here’s a complete list:
• Safety lock, small (for 3/8-in circuit breakers), NSN 5925-01-581-4662 and PN 296050002-1
• Safety lock, large (for 7/16-in circuit breakers), NSN 5925-01-609-6121 and PN 296050008
• Safety lock sleeve, NSN 5925-01-609-6208 and PN 296050009
• Clip for safety lock and sleeve, NSN 5925-01-609-6211 and PN 296050018
• Safety lock kit (contains 10 small safety locks, 2 large safety locks, 12 safety lock sleeves, 12 warnings/danger tags and 12 clips), NSN 5935-01-609-6893 and PN 296050020-1
• Safety lock kit (contains 18 small safety locks, 18 warning/danger tags, and 18 clips), NSN 5935-01-609-6266 and 296050020-2