Harkins safety Logo
My Two-Wheeler
My Two-Wheeler

Lock It Out

When electricity was in its infancy, a battle between inventors forever changed the way we use our most popular power source.  Here’s the story.

In 1882, all the electricity in the country was supplied by direct current, thanks to the inventiveness and industriousness of Thomas Edison.  Then in 1884 Edison hired the brilliant Croatian scientist, inventor and theoretician Nikola Tesla to sort out the problems with the DC system.  Tesla saved Edison $100,000, -over $1 million by today’s standards.  However, the scientists had a falling out.

Tesla left Edison’s company and went on to invent a better system, alternating current and eventually signed a contract with George Westinghouse.  AC offered several advantages.  For example, it could be stepped up and transmitted over long distances on thin wires, while DC required a large power plant every square mile and very thick cables.

Because Edison was heavily invested in direct current, he attempted to discredit Tesla. Edison staged “experiments” involving animal electrocution to try to show that Tesla’s system was dangerous.  Tesla retaliated with his own demonstrations to show that alternating current was controllable. He used his invention, the Tesla Coil, to generate huge lightning bolts to the amazement of his supporters.

In the end, AC won out, and Tesla was vindicated.  He also realized his dream of bringing affordable, abundant electric power to homes and businesss through- out the country.  Although they did not agree on the merits of AC versus DC, both Tesla and Edison knew that electricity is a powerful force to be used only with great caution and respect.  The same holds true today.

*When you follow lock-out and tag out each and every time machinery is shut down for repair or maintenance.

*Before starting work on an engine, motor, lathe, saw or any power driven equipment, take all of the steps required to neutralize the power sources.

*Place locks and warning tags on all switch boxes, valves and controls.

*Clearly print complete information on the tag so that others know when, where and why the equipment was locked out.

Short-Circuit An Accident…Always Lock Out and Tag Out

* Copyright 2002 Harkins Safety (B-155)