Relay testing has long been one of the more technically demanding and complicated aspects of the business of electrical acceptance and maintenance testing. The plethora of skills required to be an excellent relay technician includes (in no particular order) electrical theory, power system design, AC and DC control drawing interpretation, and the ability to simulate power system faults to name …
Numerous articles have been written about NFPA 70B in recent months following the recommended practice becoming a standard. All this chatter and renewed interest is coming from the perception — and rightfully so — that failure to perform minimum electrical maintenance could lead to OSHA fines. I’d like to believe that facilities that did not previously have an electrical maintenance …
A major event occurred at a large power plant in the southwest region. A new generator circuit breaker (GCB) had been installed for a combined cycle power block (CCPB) consisting of a gas turbine generator (CTG) and a steam turbine generator (STG). The new GCB is located on the low side of the generator step-up transformer (GSU) serving the CTG. …
Modern substation control and communication have revolutionized the ability to troubleshoot system faults and mis-operations. Event fault records and documenting every input and output provide invaluable information to help answer the question, “What happened?” However, there are hundreds of thousands of systems with legacy equipment. These systems can present seemingly baffling challenges that could necessitate several attempts (test and try) …
The most basic maintenance begins with our senses. Electrical and mechanical equipment tend to produce distinct sights, sounds, or smells before it fails. However, our senses have strict limitations. BACK TO SCIENCE CLASS Anything above zero kelvin will produce infrared radiation. There is no molecular movement at 0 K, including electron movement. When electrons move back into inner atomic orbitals (which …
Properly installed and maintained medium-voltage cable is highly reliable, and when properly installed, there is little or no maintenance to be performed. Yes, you should keep the terminations clean, and yes, you can perform a periodic VLF with tan delta or partial discharge test to trend degradation over the years. However, in my experience, the No. 1 reason cables fail …
Electrical power systems, regardless of the industry (utility substations, industrial metal-clad switchgear, hospitals, data centers), are built with crucial auxiliary systems. These systems are dependent on each other to ensure these power users have electrical systems that are safe and reliable. The DC battery system might be one of the more critical of these systems. DC batteries provide power to …
Becoming a great company doesn’t happen overnight. Instead, it is about small, incremental steps as we progress down the road of becoming better and better at what we do and how we do it. This is the most critical as it relates to our safety processes and safety culture. It is important to note that the first step in making …
“It’s faster for us to put on the 40-calorie suit to rack breakers out than it is to use the remote racking system,” the customer said — and I wanted to add, “Yes, the remote racking system bought for your safety at a significant investment from your company.” But I did my best to hide my dismay and took the …
AES personnel were dispatched to a gas plant in northern Alberta, Canada, for emergency repair of a failed 600 v MCC bus. Before the technicians arrived, the 600 v bus components had already been disassembled by facility personnel to prepare for installation of a new MCC section. For our client, getting the facility back up and running was more critical than …