Prevention is better than cure: why should your business monitor power quality?

 
On August 9, 2019, a lightning storm caused blackouts across parts of the UK. Although the blackout lasted for less than an hour, around one million people were affected. In light of this event, John Mitchell, global sales & marketing director at supply, installation and repair specialist CP Automation, explains why modern power protection is essential for your facility.

The lightning storm caused major disruption across England, Wales and some parts of Scotland. Even though all customers were restored within 45 minutes — the knock-on impact to services were significant. Rail services for example, experienced major delays for 48 hours following the event. Unfortunately, this lightning storm isn’t a freak one-off, nor are lightning storms the only cause of blackouts.

Transients, interruptions, harmonics, swells, dips, sags and unbalance. These are just some of the power quality problems that can have devastating effects for industrial businesses. Power quality deviations may originate within the source of supply, load equipment or from interactions between the source and the load.

While utilities are finding ways to decrease the number of outages and restore power quickly by improving the reliability and resilience of the grid, what can businesses do to safeguard their operations? Effective power system protection and power quality monitoring can take different forms but should protect your business from downtime, data loss and equipment damage.

Preventing downtime

Downtime can lead to production loss, which is financially disabling for any business, especially in an industrial environment where businesses are under pressure to increase the efficiency of their operations. Preventing downtime should therefore be a priority for businesses of all sizes. Power outages are a major cause of downtime and, unfortunately, they’re on the rise. Businesses can however take steps to diminish the impact of power outages, by installing an uninterruptible power supply (UPS).

 

A UPS is designed to provide a secondary or backup power in the event of loss of utility power. The first step in implementing a new UPS system, is establishing whether a facility requires a single- or 3-phase UPS. Generally, loads of 20kVA or less can safely use a single-phase UPS, whereas larger loads will likely need a 3-phase UPS. The rating of the UPS will be determined by the type of supply, the load being drawn by the system (kVa value) and the supply voltage.

Preventing data loss

Data is a powerful business tool, so preventing data loss should be high on every business’s agenda. Data loss can happen due to human error, hardware malfunctions and also through power failure. There are a few things your business can do to manage this scenario. Firstly, make sure that offsite data backups are available. Secondly, invest in a reliable surge protection device (SPD) and a UPS system. This may prove valuable in preventing a forced shutdown, providing valuable additional minutes to retrieve data.

Protecting equipment from premature failure

There’s more to power protection than preventing power outages. The sine wave has remained the same since the late 1800s, however the sensitivity of the equipment that is connected to the grid has dramatically increased. Transient surges and harmonic distortion are two common power quality issues.

A basic SPD and a variable frequency drive (VFD) may be used in conjunction to mitigate the damaging impact of high-power surges. However, even with basic surge protection, many facilities are still faced with some machine breakdowns due to low level switching transient events.

Transient surges are a brief change in voltage frequency that occur thousands of times a day but are very damaging to electrical equipment. The additional peaks and troughs in the sine wave caused by transients results in confusion to sensitive devices such as industrial computers, or CNC machines. Some facilities may believe that built-in surge protection adequately protects their equipment, however the built-in protection is not doing enough to protect valuable systems and prevent false zero crossings caused by transients.

Consider this as an example. High power electrical devices such as elevators and air conditioning systems or components like compressors and motors, require large amounts of energy to turn on and off. This switching creates a sudden and short demand for power, which can deviate from the normal voltage flow in the electrical system. If adequate protection is not in place, over time this can lead to premature wear of components and in severe cases, can lead to immediate component failure.

Similarly, the damage caused by harmonics can seriously impact equipment service life. The thermal stress on components can cause excessive wear and premature failure. The rise of non-linear loads in industrial environments has resulted in the growing problem of harmonic currents. The most common symptoms include voltage notching, motor vibration, arcing on bearings, nuisance tripping, electromagnetic interference (EMI/RFI) and overheating.

So, how can this be combated? Harmonic filters monitor the network and inject the necessary amount of compensation current at any given time, which restores current waveform and lowers current consumption. This makes the devices ideal for installations in which current load changes constantly, such as in IT applications and data centres.

What next?

Due to rapid advancements in equipment, varied approaches to the identification and mitigation of power quality issues have arisen. This has led to some facilities using setups which are outdated and no longer fit for purpose.

So, how do you decide which power quality products you need? Performing a site audit is a good place to start. This will identify the power quality problems that are plaguing your facility, so that you can choose the right surge protectors, harmonic filters and power quality analysers to mitigate damage.

Whether facility managers choose to completely update their power protection devices, or enhance what they already have, monitoring the electrical characteristics in your facility can result in less downtime, limit data loss and protect valuable equipment from damage.

CP Automation offers a range of products and services to tackle power quality problems. Its four point Mission to MARS service: measure, analyse, report, solve, offers a complete power quality service from site measurements to product installation. Visit www.cpaltd.net for further information.