Three Things Engineers Should Know About Power Protection
In order to equip EE’s with the knowledge they need to design and optimize equipment, extend equipment life cycles, reduce failures, and manage risk, it is worth keeping a few key points in mind about protecting power.
Electrical engineers understand better than anyone the importance of electrical power in driving life forward. While expertise or specialty from one electrical engineer to another varies due to operation in such a broad field, understanding power unites them. In order to equip EE’s with the knowledge they need to design and optimize equipment, extend equipment life cycles, reduce failures, and manage risk, it is worth keeping a few key points in mind about protecting power.
This is true now more than ever, as the pandemic transitioned many of the last vestiges of pre-digital productivity onto networked devices and platforms, poor power can no longer be functionally worked around. In the past, a school could have students read reports. An office could have workers organize files. A clinical lab could have technicians do data entry. All of these tasks are now done digitally, which means if the power is unreliable, their operations grind to a halt.
Image courtesy of Powervar.
Bad Weather is Only a Small Piece of the Puzzle
When catastrophic power events are brought up, the mind naturally conjures up imagery of thunderstorms but many are surprised to learn that storms, and other natural occurrences, only account for about 10 percent of power issues, according to industry experts. The remaining 90 percent come from within the facility itself. Anything that runs on electricity creates electrical noise in a power environment, which includes everything from machines or equipment in the vicinity, the building’s HVAC systems, and even overhead lighting.
These systems are mission-critical for keeping building operations up and running, but they can also produce electrical impulses, high-frequency noise, and high-voltage transients. This noise leads to variance in power quality — irregular swells, sags, and spikes in the smooth sinewave electrical engineers prefer to see. That variance can easily disrupt sensitive electrical equipment in a way that can be hard to detect in real-time, largely because many believe that power availability is the same as power quality.
Power Availability Does Not Represent Power Quality
A common belief is that if the lights turn on, power is being delivered and if they don’t, there’s a problem. That is only half right. While the inability to turn on the lights certainly indicates that a power environment has been compromised, the lights being on is no evidence that the power environment (and the power within) is clean, consistent, and free from voltage spikes or drops. This is relevant because while clean power leads to consistent performance, inconsistent power into a machine leads to inconsistent performance.
The difficult truth is, systems are actually most vulnerable when the power is on. Though power disturbances are most visible during an electrical outage, 90 percent of power disturbances stem from the internal environment and occur while the system is seemingly operating normally. Spikes, normal-mode noise, and common-mode noise are present to some degree all the time but left unchecked, these disturbances can lead to downtime, data errors, inaccurate measurements, shortened equipment life, and increased service calls.
While you might assume that costly equipment is built to handle a bit of wear and tear, this is decidedly not the case with highly calibrated, sensitive electronics. Dirty power won’t necessarily destroy equipment, just as low-octane gasoline won’t crash your car. The issues it causes come in the form of degradation, system lockup, undetected data logic errors, which all contribute to the slow erosion of system components and performance levels. These are issues that legacy power protection products like surge protectors and backup generators aren’t equipped to address.
Power Protection is a Multi-pronged Approach – A Surge Protector or Generator is Not Enough
In technical terms, a “surge” is a high voltage transient or impulse. Surge protectors are designed to divert this impulse away from the sensitive electronic systems they protect but this does not eliminate the impulse. That means the power problem persists and the system strains. Many surge protectors are also functionally one-time-use only or degrade over time, with performance subject to their respective clamping voltage and response times. They are useful, especially in the residential or light commercial market, but they don’t offer enough protection for more robust environments.
A majority of commercial-level power protection solutions deploy a surge diverter, noise filter, or both, but the most important element of power protection is actually a low impedance isolation transformer. This specialized feature acts to isolate the powered instrument from the power source and re-establishes the neutral-ground bond without opposing or disrupting the current path. The device is then truly protected from unwanted noise without negatively affecting power flow. This ensures only clean, reliable power consistently flows to and through devices.
But what if the power goes out entirely? A backup generator is designed to keep your most essential equipment running in the event of a blackout, but what if all your equipment is essential? A backup generator is not as productive or reliable as regular power from the grid, so it will be forced to prioritize where its power is diverted. Alternatively, the whole environment can run on reduced power. One major drawback is that a generator can take up to 45 seconds to start up and supply power, an eternity to unprotected sensitive electronic systems. Either way, this is less than ideal — especially when considering that a traditional backup generator does not provide power conditioning when not actively in use.
Powervar's GTS Series of uninterruptible power supplies. Image courtesy of Powervar.
An uninterruptible power supply (UPS), on the other hand, not only delivers reliable, clean, and uninterruptible power when active, but also features a low impedance isolation transformer with a high load inrush capacity. Leading UPS models also include an internal maintenance bypass system, customizable PDU, wide input voltage range, and integrated SNMP capability. Some even feature hot-swappable batteries to allow the unit to stay online during maintenance. An additional and highly beneficial element of a sound UPS system is that it provides a central, clean grounding point for all components.
Clean Power Saves Money, Time, and Reputation
At the end of the day, power protection is about proactively mitigating and managing the risk to equipment from power-related failures including performance degradation, erosion of sensitive conductors, components, and circuits from low-amplitude power disturbances, and surges. EE’s cannot wait for electrical issues to happen – they need to be proactive. Power quality solutions are the simplest way to accomplish that.
About the Author
Michael Creighton is the director of engineering at Powervar. With three decades of experience in research and development of power technologies, he is an esteemed leader in engineering, research and development, and innovation for the power management industry. Michael joined the AMETEK Powervar team in 2012, where he is pivotal in the development of the highest quality power products to keep businesses operating and in business.