General Electrical Safety

The outline below provides Electrical safety precautions:

• Only qualified technicians familiar with the system, using an up-to-date set of system schematics, should perform electrical/electronic system troubleshooting or maintenance.
• Avoid wearing glasses that have a metal frame.
• Avoid wearing necklaces, watches, bracelets, earrings, rings, or chains that are made of a metallic substance.
• It must be always assumed that power is "ON" so all conditions must be treated as live. This practice develops a caution that may prevent an accident.
• Ground connections cause fault currents to flow directly into the ground instead of flowing through the body into the ground. All electrical apparatus must be properly grounded.
• Always use electrically insulated tools and utilize shock avoidance techniques.
• Remove Load from circuit or equipment. Before performing maintenance or service on any part of the Electrical System, perform all applicable LOTO procedures.
• Before performing any work on the system, verify that power is removed from all circuits.
• Electrical panels must not be opened if the ground light is on by anyone other than a qualified, authorized electrician for any reason.
• Capacitors must be given time to discharge, otherwise it should be done manually with care.
• Before any repair work is conducted on electrical circuitry, a voltage check using the proper test equipment must be made to ensure that dangerous voltages do not remain in the circuitry.

Test equipment must be checked at regular intervals.

• USE CAUTION when connecting test equipment probes to test points. Shock hazards could exist at the test points or in the test point area and/or transients induced by the probes could cause a machine action.
• If it is necessary to perform troubleshooting with the power on, know where power is present and proceed with extreme caution. Whenever possible, use electrically insulated tools. When troubleshooting "LIVE" equipment, take the following precautions:
• Make certain your tools and body are clear of potential grounds.
• Use extra precaution in damp areas.
• Be alert and work without any outside distraction.
• When servicing electrical enclosures, follow all PPE (personal protective equipment) requirements per posted arc flash warnings in accordance with plant safety specifications.
• Orange wire (or wires tagged with orange ends) identifies circuits that receive power from an external source, for example, an electrical enclosure lighting circuit. These circuits may still have power when the main disconnect switch or circuit breaker associated with the Electrical System is OPEN. Use extreme caution when working where this type of circuit is present.
• When conductors are replaced, they must conform to the manufacturer's specifications, including proper color-coding.
• Always use an appropriate fuse puller. Only regulation fuses, with their physical and electrical characteristics clearly specified, are to be used as replacements. Never attempt to replace a specified fuse with a higher-rated fuse (such as replacing a 5-amp fuse with a 10-amp fuse).
• Before applying power to any equipment, establish, without any doubt, that all persons are clear.
• The control panel doors shall be open only when it is necessary to check out the electrical equipment or wiring. After closing the door, make certain that the disconnecting means is operating properly with the disconnect handle mechanism.
• All covers on junction boxes must be closed before leaving any job.
• Before restarting equipment, read and understand all warnings, markings, and notices.
  • Read all markings such as nameplates and identification plates.
  • Do not alter circuits unless authorized to do so by the manufacturer.
  • Do not alter or bypass protective interlocks.
  • Do not place jumper wires across fuses or trip switches.
  • Do not alter over-current protective devices.
• Refer to the Motor LOTO Procedures for the proper procedure of verifying the complete lockout of power sources.