How can you avoid shocks?
Breaker or switch operation … ON/OFF
Removal of covers to expose live parts
Application of safety grounds
Defined as :
A state in which the conductor or circuit part to be worked on or near has been:
Disconnected from energized parts
Locked/tagged in accordance with established standards
Tested to ensure the absence of voltage
Grounded if determined necessary
It is essential to CONFIRM it is de-energized.
NOT CONFIRMED = LIVE PPE required
In recent years, neutral currents problems are coming to the fore.
Clamp-on to measure :
Unbalanced loads … ex.. 347 lighting
3rd harmonic….ex.. lighting & computer circuits
Stray current….ex… from utilities at power entry.
Some measured currents were up to 10 amps