As more businesses rely on automation, protecting your control panels from sudden voltage spikes is becoming increasingly important.
In this blog, Interpanel explains what causes electrical surges, how surge protection works in the UK, and why it is crucial for your control panels and automation systems.
What causes an electrical surge?
Electrical surges, or transient over-voltages, are short bursts of excessive voltage that can damage sensitive electrical equipment. They can be caused by external factors like lightning strikes or faults on the power network, or internal sources such as motors, switching devices or large inductive loads.
While the UK grid is generally stable, surge events are becoming increasingly common due to changing weather patterns and the growing use of sensitive electronic and automation equipment. The more automated your operation, the greater the potential impact of a surge.
What is surge protection?
Surge protection refers to a set of measures and devices designed to prevent or mitigate the harmful effects of transient over-voltage events. Essentially the idea is not to stop the surge (it’s almost impossible to eliminate entirely) but to redirect or absorb the excess energy so that sensitive equipment downstream is not exposed to destructive voltages.
For control panels and automation systems, this means installing surge protective devices (SPDs) at strategic points in the distribution or control network so that the incoming voltage to the panel remains within acceptable bounds and doesn’t generate unexpected faults, equipment damage or unexpected downtime.
A good surge protection scheme should be part of your business’s reliability strategy. It means your drives, sensors, motor control centres (MCCs) and other automation equipment are safeguarded against spikes or bursts of voltage, whether these are caused externally or internally.
What types of SPDs are there?
In industrial applications, the standard classification of SPDs is type 1, type 2 and type 3. Here’s a breakdown of how they each apply to control panels/automation systems:
- Type 1 SPD: Installed at the origin of the installation and designed to cope with very high surge currents, for example those caused by direct lightning strikes or major external surge events.
- Type 2 SPD: Installed downstream and designed to protect against switching surges, indirect lightning surges, or surges generated by the installation itself (e.g. motor switching).
- Type 3 SPD: Installed as close as possible to sensitive equipment and act as the “last line of defence” to catch any residual surge energy that gets past type 1 and type 2 protection.
For control panels, you’d typically want to adopt a layered approach, with a strong SPD at the supply origin, another at the panel/distribution level, and then close protection for the most critical downstream loads. Type 2 and type 3 SPDs can be tailored specifically to your individual control panels and MCCs.
What are the benefits of having surge protection?
Reduced risk of equipment damage.
Surges that are not blocked or diverted can at best degrade electronics and shorten component life, or at worst cause catastrophic failure of drives, controllers or sensors.
Minimised downtime
If your panel fails because of a surge event, you may face unplanned production downtime, lost productivity, eyewatering maintenance costs and potential safety issues.
Improved reliability and predictability
Surge protection makes your system more stable and consistent, so you’re not left worrying that the next voltage spike will cause a failure.
Extended lifespan of systems
Even smaller surges that don’t immediately knock equipment out could still gradually degrade components. Over time this causes maintenance cost creep and reliability problems.
Value for money
While adding SPDs comes at a small cost, the alternative (panel replacement, drive failure, sensors, lost production) can be far more expensive.
Safety and compliance
With more attention on power quality and protection, properly specified surge protection forms part of the overall electrical integrity and risk-mitigation for a business.
Is surge protection a legal requirement for UK businesses?
BS 7671:2018 (18th Edition of the IET Wiring Regulations) requires Surge Protection Devices (SPDs) where surges could cause serious injury, equipment damage, or operational disruption.
Can surge protection be retrofitted?
The short answer is yes; existing control panels and automation systems can easily be upgraded with surge protection. At Interpanel, our engineers can install the full range of SPDs in new or existing control panels, to relevant standards (BS 7671 and IEC 61439) and with minimal downtime.
Because SPD installation can often be incorporated your current panel enclosure, physical disruption is typically limited, and you don’t necessarily have to rip out existing panels or rebuild everything.