An electric arc flash produces the highest temperatures on earth—up to 35,000 °F (19,426 °C)—causing all materials (metals, liquids, plastic) to vaporize and expand explosively. The blast pressure can throw a person across a room, and spray a person with shrapnel and molten metal droplets. Aside from the primary danger of being burned, intense pressure and sound can cause physical injury and deafness.
The input power requirements for a large motor drive puts it in the high risk category for arc flash. Electrical shock is more commonplace. A slip of the hand and you or your tool connects with a live component. It happens when you’re working too fast or you get distracted while working. Not as destructive as an arc blast, but still deadly. Here are some guidelines for conducting motor troubleshooting safely.
In addition to wearing the proper personal protective equipment (PPE), it’s critical to assess whether your test tools meet safety requirements. Look for the symbol of an independent testing lab such as UL, CSA, TÜV or other nationally recognized testing laboratory (NRTL).
Troubleshooting any motor drive is for trained, certified technicians only. NFPA 70E specifies workers must be qualified persons to troubleshoot in this environment.
For more information on Electrical Safety, see our online course available at the Fluke eLearning Center.