Guest Lecture Asst. Electician
25 Jul 2020
Don Bosco Tech Society, Jalandhar, Punjab organized a guest lecture on July 25, 2020. This lecture was delivered by Mr. Sanjeev Kumar Jhangra, the owner of Jhangra Contractors. At the request of our trainer Mr. Deepak Chana, he delivered a guest lecture to the trainees . 14 students attended this session via Zoom App.
“The electricity that powers machines, tools, and other experimental apparatus must be handled with care and attention. Bodily contact with high voltage and current can cause muscular spasms, burns, cardiac arrest, and even death. Even small amounts of current passed through the body can cause electrocution. 10 milliamps can induce muscle contractions, loss of muscular control, and the inability to let go. 10 microamps through the heart can cause ventricular fibrillation. Laboratory experiments typically use equipment that complies with International Safety Standards. The Underwriters Laboratory UL label, for example, certifies that equipment meets these standards, which prevents certain types of hazardous exposure. However, electrical inputs and outputs, or customized equipment still pose a hazard. This video will present electrical safety precautions and introduce common electrical equipment used in many types of laboratory experiments.
When using electrical equipment, wear long pants, closed-toe shoes, and appropriate personal protective equipment. Avoid loose clothing, and remove any dangling or metal accessories that can accidentally contact electricity. In the United States, single-phase AC power from a wall outlet is 120 Volts. Outlets for three-phase AC power can provide up to 480 volts and over 10 amps. So power sources must be handled with respect. A clean lab environment is important for mitigating hazards. Avoid loose or frayed wires, cables, and connections. Know how to turn off all equipment, power supplies, and circuit breakers. Make sure that at least two people work on an experiment that has accessible DC power greater than 50 volts. Use the same precautions with single-phase or three-phase AC main power. Assume any exposed metal carries live electricity unless verified. Before changing a setup, turn off or unplug power sources used in the experiment. Proper grounding of equipment ensures the chassis is at earth-ground potential, which prevents electrical shock. Always plug equipment into AC outlets with the power cord intended for it. Equipment that is hotter than expected is both a hazard and a symptom of a problem that should be addressed. Finally, turn off all equipment after an experiment is finished, and turn off unused equipment before leaving the lab. Now that basic safety precautions have been presented, the operation of some common electrical equipment will be demonstrated in the laboratory Trainees.
Don Bosco Tech Society, Jalandhar thanked Mr. Jhangra for delivering this valuable lecture.