Training provides tips on power, VFDs, standards

Engineering education can help with motors, drives, and lightning control in industrial and commercial applications in retrofit and with new designs. See five misconceptions in applying motor controls.

By Control Engineering July 31, 2018

Training programs in technology filled centers, road shows, and online help present and future engineers gather and adapt knowledge to meet design and application needs. Explaining related trends for electrical, motion control, and automation training are:

  • Dan Carnovale, manager, Power Systems Experience Center, Eaton
  • Allan Clark, manager, Eaton Experience Centers
  • Rob Fenton, manager, advanced controls solutions, Eaton.

Q: What training programs are available?

Carnovale: Hands-on and visual learning address a variety of application environments for electrical equipment in application settings from utility power distribution and substations to the plug in a residential setting. Industrial and commercial applications are used to demonstrate actual loads for motors, drives, and lightning control. Training is focused on system design, reliability, efficiency and safety.

Classroom sessions reinforce concepts that are discussed during tours and coordinated with hands-on interaction, where possible, to reinforce learning. Electrical concepts are especially difficult to understand; visual concepts and analogies are intermixed with technical discussions. Videos cover codes and standards, arc flash safety, energy saving approaches, and other topics. A virtual tour posted online allows a virtual walk-through of the training facilities.

Fenton: Instructor-led classes, self-guided online training, and videos demonstrate how to program and troubleshoot products; interactive online training allows the student to interact and practice with a product simulator that mimics a real-world environment.

Q: What are the students’ goals?

Carnovale: If the student has an engineering background, they are looking to see how things "physically" work and are connected, built and constructed. Engineers are often in the dark coming out of school when it comes to physical attributes of electrical equipment.

If they are electricians, they are looking for information on the "applications" because they all tell us the same thing—when they are in their apprentice program they learn how to make things look good, connect them, etc. Right before the power is turned on, they go to the next site and don’t get to see if they missed anything from an application consideration standpoint like lead length on surge protectors, harmonics, etc. For more experienced engineers and electricians, they are usually looking for new technologies to make systems more reliable or safe.

Fenton: Students can gain some familiarity with products and applications and how to select the right product features. They can learn how to program or troubleshoot a product.

Q: How can motor control help with energy efficiency?

Carnovale: Understanding the requirements of the application is critical to selecting the right control equipment to start and run motors. Energy savings and unique control situations help with selecting the technology used. For example, for across the line applications, motor overloads can be as simple as a thermal "heater" or as complicated as a current and voltage sensing motor relay. The application and cost will dictate the selected device. With energy savings, running speed, and operational scenarios will dictate the drive selected and how it is matched with the motor.

Q: Do variable frequency drives (VFDs) have challenges?

Carnovale: Most non-programming issues with drives involve either harmonics or voltage sags. Both are solved with well-proven strategies and can be seen/learned in training. Additional issues involve using old motors [not rated for the pulse-width modulation (PWM) voltage output on drives] with drives, bearing fluting/damage, and interaction with weak sources (such as generators).

Fenton: Using VFDs and control products such as overloads and soft starters are the single biggest way to save energy. For example, with centrifugal pump or fan, use of a VFD allows significant energy savings to reduce the speed of the pump or fan. Other applications can benefit from using communicating motor control devices (overloads, VFDs and soft starters), which enable the user to monitor the energy used by the motor. After measuring and monitoring energy usage, energy management can start.

The skill level of the personnel designing, installing, and maintaining the system with these devices needs improvement. New challenges include noise interference, communication network faults, power conditioning, and harmonics. They require personnel that are knowledgeable in communications using computers and programing. New training focuses on improving these skills.

Q: What are common training requests?

Carnovale: Training sessions for motors, drives, and control including one on motor starting, with power system modeling. Other topics include power system harmonics, startup, commissioning and operation of drives, control equipment connectivity, drives, and automation.

Q: Are there misconceptions in applying motor controls?

Carnovale: Common misconceptions include:

  1. It’s incorrect that power factor correction devices are great energy savers. Many people are fooled by vendors selling power factor correction, harmonic filters or other devices that compensate for current (but not necessarily kilowatts or real power).
  2. It’s incorrect that drives are OK to be used in lieu of a soft starter even if operated at 60 Hz; doing so would use more power than without the drive (either across the line or with a soft starter with the bypass contactor).
  3. It’s incorrect soft starters will relieve demand charges; time to start a motor is much less than the 15-minute window for demand charges and, in addition, most starting current is reactive so it won’t save real power or kW for the consumer
  4. It’s incorrect harmonics are always a problem. Harmonics are not a problem unless they area problem; it’s necessary to understand how they work.
  5. It’s incorrect harmonics waste significant energy. They are like power factor losses and typically amount to 1 to 4% of energy loss in power systems.

Q: What training methods are used?

Carnovale: Hands-on, full-scale demonstration with drives, motors, control equipment, and motor control centers (MCCs) operate on real power systems and show "good, better and best" opportunities for design, energy savings, and other scenarios.

Clark: Hands-on labs integrate common problems from the field and replicate challenges in a controlled and safe environment. Mobile training vehicles visit remote destinations; online tools, blogs, and videos provide expertise.

Q: Are there training challenges?

Carnovale: An environment that could be electrically "unsafe" is addressed by having very close controls and limits on fault current (such as limiting arc flash), limited options for switching (such as use of remote controls for reconfiguring systems), and highly trained and experienced trainers for each class.

Clark: The industry’s technology adoption rate presents a unique opportunity to integrate technology into facilities, recreate the common issues faced in the field, and demonstrate (in real-time) the advantages of adopting the technology.

Q: Are codes and standards addressed?

Carnovale: Hands-on training programs help support a better understanding of National Fire Protection Association (NFPA) 70E, the National Electrical Code (NEC), and NEC-500/505.

Q: How is training changing?

Carnovale: Training is evolving to mimic a lot of what we use for personal knowledge, including YouTube, websites, and "how to" self-paced do-it-yourself videos.

Clark: Through application vignettes, a three-pillar model integrates a classroom setting for theoretical content delivery:

  1. Hands-on labs allow immersion into technical design
  2. Installation practices and troubleshooting scenarios
  3. Interactive application environments enable advanced technical competency through a simulated application.

This approach to training enables competency development while aligning to customer challenges in the field, incorporating global codes and standards, and using industry association content. Training can simplify design and installations, mitigate common challenges, and increase and protect personnel that interact with the electrical systems.

Edited by Mark T. Hoske, content manager, Control Engineering, CFE Media, mhoske@cfemedia.com

KEYWORDS: Engineering education, motion control

Training helps with design and operating motion control, electrical, and automation applications.

Knowledge of standards help with power, variable frequency drives, and standards

Myths related to drives and starters should be dispelled.

CONSIDER THIS

Do existing and future personnel have experience and knowledge needed? 

ONLINE EXTRA

Eaton has Experience Centers in Pittsburgh and Houston. www.eaton.com/experience