Many services offered by ERS involve maintaining uninterruptible power supply (UPS) systems.
Since its introduction nearly 40 years ago, the 555 timer IC and its companion 556 dual timer have inspired hobbyists, technicians, inventors, engineers, and many others who love to experiment with electronic circuits. An Internet search on "555 timer" yields millions of hits. Using "555 timer projects" as the search phrase yields more than 800,000 hits.
As we have seen, power problems have a bad effect on electronic devices. To detect a power problem, a technician will first check out the power supply to a device to make sure it is functioning properly.