Testing control circuits
Problem: How can you test 12 and 24-V control circuits in discrete relay and PLC control panels? Solution: A 24-V LED panel lamp assembly with a concentric Fresnel lens and 6-in.
Problem: How can you test 12 and 24-V control circuits in discrete relay and PLC control panels?
Solution: A 24-V LED panel lamp assembly with a concentric Fresnel lens and 6-in. long color-coded leads serves as an accurate, inexpensive test probe by tinning the ends of the leads. You can detect ac and dc from 5-33 V and one-shot voltage pulses as short as 1/10 sec, and identify the dc connection. Most of my plant's power supplies have current limit protection and the short circuit condition of 4-5 V is readily apparent. At 33 V the tester only loads the circuit under test by 25 milliamperes. I have modified a second lamp by soldering booted alligator clips to the leads for hands-free operation.
Contributor: Allen Sellers, Machine Maintenance Electrician, Lancaster, OH
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Annual Salary Survey
Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.
There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.
But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.
Read more: 2015 Salary Survey