AVR Maintenance:
How Voltage Regulators can Achieve Zero Maintenance?

14 Aug 2022

Est. Reading Time: 10 minutes


When it comes to investing in a new Voltage Regulator or Industrial Voltage Stabilisers, Project Managers are already recognising the huge benefits of achieving a completely stabilised and protected voltage supply.


But often, what’s holding them back—is a common perception of having a series of costly and frequent maintenance that comes along with it. This fact alone causes most companies to put off all decisions to invest in such voltage solutions.


In such cases, managers would rather risk exposing connected infrastructure to harmful voltage anomalies—than having to deal with more maintenance in their operations.


On the other hand, some Automatic Voltage Regulators (AVRs) or Industrial Voltage Stabilisers are presented as irresistible offers with significantly low prices—luring uninformed purchasers and end users to easily overlook the excessive maintenance needed.


In this article, we dispel the myth and misinformation surrounding AVR maintenance—and prove how a near-zero maintenance AVR is actually possible.

Busting the AVR Maintenance Myth

All electrical or mechanical parts wear and tear over time. But compared to the maintenance needed for other electrical equipment like a UPS, maintaining and servicing an AVR unit is in fact one of the most effortless processes despite the presence of internal moving parts. 


Thus, you do not have to worry about frequent shutdowns or costly part replacements if recommended guidelines are followed during installation and usage.

For example, an AVR shouldn’t be installed in a structure exposed to excessive vibration, electrical shock, or moisture. Nor should you use an AVR as a primary surge arrester despite its capability to limit voltage spikes. A separate arrester should be used to protect equipment from lightning surges.  


AVR maintenance cost is affordable and reasonable when you proactively schedule preventive maintenance. Like every other piece of equipment, preventive maintenance is less expensive than emergency repairs.

The bottom line — While AVR maintenance is necessary, it can actually be a simple and seamless process. Here’s why… 

What happens during AVR Maintenance

Voltage regulators play an essential role in providing clean, stable, and precise voltage levels to equipment. They also double up as protectionary modules against surges, fluctuation, and other transient events. In doing so, over time AVRs will require timely maintenance to prevent breakdowns.

When an AVR is due for scheduled maintenance, qualified technicians will perform ocular inspection and necessary part replacements. For example, they check for wear and tear of mechanical parts and replace them if necessary. 


However, the frequency and severity of wear and tear differ by the technologies driving the AVR. An AVR’s robustness and healthy lifespan are also influenced by the manufacturer’s design and construction quality. 


Since not all AVRs are created equally, we’ll deep dive into 3 different AVR designs, and explore the level of maintenance needed for each of them.

AVR Maintenance in 3 Voltage Solutions

Static AVR

Also known as tap-switching voltage regulators, these AVRs are touted as an economical solution for stabilising load voltage. However, customers who purchased static AVRs often regret their choice, as the voltage stabilising units break down easily, particularly in harsh operating conditions. Consequently, technicians are called in frequently to service, repair, or replace the AVRs. 

A static AVR is electronically driven by an array of silicon-controlled rectifiers (SCR) to adjust the transformer’s winding ratio. SCRs are prone to in-rush current and voltage fluctuation. Besides, it takes time to trigger the required number of SCR sequentially to adjust the output level. This leads to component failure and secondary damages that can be costly. 


The SCRs and underlying electronic modules are susceptible to electrical noises. Sometimes, electrical interference could couple into the SCRs signal path and cause the SCR to behave erratically, which might lead to unplanned downtime. Hence, It isn’t exaggerating to label static AVRs as high-maintenance units.


Costly and cumbersome maintenance aren’t the only limitations of static AVRs. Find out how static AVRs are riddled with flaws here.

Servo AVR

Servo AVRs offer a balance of performance, reliability, durability, and costs. While they are not entirely maintenance-free, servo AVRs can operate reliably for years before parts replacement is needed. Unlike static AVRs, servo regulators have better tolerance against voltage fluctuations and inrush current.

Still, minimal preventive maintenance is necessary for a servo AVR due to its mechanical rotational design. Servo AVRs consist of a carbon brush that adjusts the autotransformer position based on the servo’s position. Frequent movement of the rotor to compensate for fluctuating incoming voltage gradually wears off the carbon brush. 


Therefore, you’ll need to check and replace the carbon brush after a few years to ensure that the Servo AVRs maintain optimal performance. However, for a more robust setup, Servo AVRs with high-quality carbon brushes will last longer and require much less maintenance. 


Annual ocular inspections are recommended to spot premature degradation of the carbon brush, shafts, and bearings. 


Despite the need for annual maintenance, servo AVR proves to be an economically-viable choice to protect expensive equipment and facilities from voltage irregularities. The cost of maintaining servo AVRs is justifiable for the durability and prolonged lifespan of the serviced units. Explore how Servo AVRs can benefit your operations.

Magnetic Induction AVR

The magnetic induction Automatic voltage regulator is the closest you’ll get to a zero-maintenance AVR. Companies that need to install an AVR in remote or harsh environments choose magnetic induction AVRs because of their immense durability and near-zero maintenance design. These AVRs can function reliably for years without interruptions. 

The secret of a magnetic induction AVR’s robustness lies in its brushless technology. A magnetic induction AVR incorporates a brushless motor that uses electrical energy to create rotational force. It doesn’t rely on a brush to supply power to the commutator. Hence, rotors in magnetic induction AVRs can rotate without resistance and do not heat up from the frictional force. 


In most cases, quality is relative to the price we pay. For the immense benefits that the magnetic induction AVR offers, the investment is worthwhile because of its virtually maintenance-free features. 


Businesses choose these ‘Plug-and-Forget’ AVRs for mission-critical applications that cannot afford unplanned downtime.

Ashley Edison empowers businesses


As a leading voltage regulation solution provider, Ashley Edison recognises the industry’s need for low-maintenance AVRs. Through decades of engineering advancement, the Ashley Edison team has refined various aspects of AVR designs to ensure our products are intuitive, simple, and durable.


We provide voltage regulation solutions to help optimise our client’s operation. For applications where periodic maintenance is not viable or almost impossible—clients find their answers in our series of magnetic induction AVRs, which are built for precision, reliability, and ruggedness in harsh operating conditions. 

For example, Total Energies installed Ashley Edison’s magnetic induction AVRs to stabilise power transmission in Angola.


Likewise, Singapore Power uses our near-zero magnetic induction AVRs to mitigate voltage drop issues over 7.4 km long transmission cables.

In Conclusion

For most AVR designs, preventive maintenance is still necessary from time to time to ensure that the automatic voltage regulators are performing at their optimal levels. Maintenance is neither complicated nor expensive if you proactively schedule preventive maintenance and follow the recommended guidelines during AVR installation and usage. The returns that an AVR delivers to your business far outweigh the cost of purchase and maintenance.


For the most effortless ‘Plug-and-Forget’ results, opt for a virtually maintenance-free solution with Ashley Edison’s Magnetic Induction AVR.

Since 1977, Ashley Edison continues to deliver total power protection with top-of-the-range customised AVR solutions that dependably optimise facilities in multiple industries—across the world.


Speak to our Voltage Specialist for a comprehensive consultation, or drop us an email at sales@ashleyedison.com to discover how you can effectively solve your power problems—permenantly.


To learn more about Ashley Edison’s Automatic Voltage Regulators, visit our product page here.

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