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Tag: electrical troubleshooting
Electrical Troubleshooting Quiz
2013-02-25 22:01:00| Electrical Construction & Maintenance
Last month, a 200 hp motor started blowing fuses every few days. It's on its own branch circuit with no other loads. This motor runs only occasionally. It turns the compressor of a supplemental plant air system, charging a supply tank to 400 psi. It starts when pressure drops to 50 PSI. If plant air pressure drops below the main compressor's ability to keep up, the tank supplies 40 psi to the plant air system. The fuses are the correct size and the same size used prior to this problem. There's no evidence of a fault, so why do those fuses keep blowing? read more
Tags: electrical
quiz
troubleshooting
electrical troubleshooting
Electrical Troubleshooting Quiz
2013-02-11 19:44:00| Electrical Construction & Maintenance
A few weeks ago, an 800A breaker tripped and could not be reclosed. So, it was replaced. The new breaker tripped several times, and a recording DMM left on it showed a maximum load of 620A. Each time, the investigating technician couldn't identify a fault before reclosing the breaker. The plant manager had a tech place a bypass jumper around it. "We've got an instrument monitoring the current and if it gets too high someone can just pull the handle." He wants you to figure out why the breaker "doesn't hold." What should you do? read more
Tags: electrical
quiz
troubleshooting
electrical troubleshooting
Electrical Troubleshooting Quiz
2013-02-11 19:44:00| Electrical Construction & Maintenance
A few weeks ago, an 800A breaker tripped and could not be reclosed. So, it was replaced. The new breaker tripped several times, and a recording DMM left on it showed a maximum load of 620A. Each time, the investigating technician couldn't identify a fault before reclosing the breaker. The plant manager had a tech place a bypass jumper around it. "We've got an instrument monitoring the current and if it gets too high someone can just pull the handle." He wants you to figure out why the breaker "doesn't hold." What should you do? read more
Tags: electrical
quiz
troubleshooting
electrical troubleshooting
Electrical Troubleshooting Quiz
2013-01-22 21:08:00| Electrical Construction & Maintenance
The plant has a wireless system that is supposed to provide real-time information about the production floor to people in the administrative offices. But sometimes the statistics and status alerts don't match actual conditions. Maintenance is receiving automated alarms that turn out to be false. And sometimes a machine simply resets itself or exhibits other undesirable behavior. The problems seem to be completely random. To eliminate outdated router problems, maintenance bought all new routers at a local office supply store, but the troubles remain. What should you do? read more
Tags: electrical
quiz
troubleshooting
electrical troubleshooting
Electrical Troubleshooting Quiz
2013-01-22 21:08:00| Electrical Construction & Maintenance
The plant has a wireless system that is supposed to provide real-time information about the production floor to people in the administrative offices. But sometimes the statistics and status alerts don't match actual conditions. Maintenance is receiving automated alarms that turn out to be false. And sometimes a machine simply resets itself or exhibits other undesirable behavior. The problems seem to be completely random. To eliminate outdated router problems, maintenance bought all new routers at a local office supply store, but the troubles remain. What should you do? read more
Tags: electrical
quiz
troubleshooting
electrical troubleshooting
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