VFD Surge Protection and Power Filtering

Transient Protection Design surge protection products are ideal for protection of Variable Frequency Drives (VFDs) manufactured by companies such as ABB, Allen Bradley, General Electric, Hitachi, Mitsubishi, Toshiba, Yaskawa, and Westinghouse. Surge protection for VFDs will improve power quality by surge protecting and power filtering the incoming power to the VFD. TPD surge protection for VFD equipment is essential to protect these valuable assets, avoid costly downtime, maintain process efficiency, prevent data loss, extend equipment lifespan, comply with safety standards, and reduce environmental impact. It's a proactive measure that contributes to the overall reliability, efficiency, and financial stability of industrial operations.

How To

Protect Variable Frequency Drives
• Install the TPX-480NN-F surge protector unit at each drive.
Or, protect multiple drives by installing a VFD surge protector at drive cabinet or motor control center.
For additional surge protection, install a small series wired surge protector unit on the circuit feeding the low voltage controls when possible.
The VFD surge protector and power filter can be placed at the drive cabinet or individual drive.

By being at any of these points, all VFD equipment can be protected from incoming surges and transients from the utility line. In addition, the VFD surge protector will protect against all the cross circuit transients generated by the variable frequency drives themselves from switching on and off which damage and degrade equipment overtime in other parts of the facility. Plus, you will clean up transients caused by the drives that can affect electronic loads in other sections of the facility. Surge protection is also recommended to protect VFD equipment when harmonics are an issue.

Protect Logic Controls and Drives
TPD manufactures many different types of suppressors, so we do not need to take a "one size fits all" approach to protecting equipment.
The three phase suppressor can be placed at the drive cabinet (or individual drive, soft start, MCC or distribution panel feeding the equipment).

By being at any of these points, you can protect all downstream equipment from incoming surges/transients from the utility line in addition to all the cross circuit transients generated by equipment switching on and off in other parts of the facility. Plus, you will clean up transients caused by the drives that can affect electronic loads in other sections of the facility.

Only the units installed at or near each drive or on each drive cabinet or MCC feeding the drives can stop the internally generated transients. Normal load switching of equipment inside any facility can surge other equipment in the facility if no suppressor is placed on each piece of equipment fed from a common bus or distribution panel. Plus, if lightning should strike the facility or near the facility and inductively couple onto building wiring, if no surge suppression unit is installed near the equipment, lightning could get onto an overhead bus or get into a distribution panel and spread out to the other circuits on that bus or distribution panel. Also, if any sub panel feeds parking lot lights, signs, security gates, rooftop HVAC equipment, or any other outside electrical equipment, lightning could strike at or near the equipment and travel back into the sub panel and then out to other circuits on that sub panel or travel to the distribution panel feeding the sub panel. Therefore, placing surge suppression at the service entrance only is not sufficient to fully protect the equipment and why it is second in priority to installing protection at the equipment level or at the distribution panel/MCC/drive cabinet feeding the individual drives and other pieces of equipment.


The Importance of Surge Protecting VFDs

Surge protection for Variable Frequency Drive (VFD) equipment is of paramount importance due to several critical factors:

Preserving Equipment Integrity
VFDs are essential components in commercial and industrial settings, controlling the speed and power of electric motors. They contain sensitive electronics, including microprocessors and power electronics. Surge events, such as voltage spikes, power company surges, or lightning strikes, can easily damage these components, leading to costly repairs or replacements. TPD surge protection safeguards the integrity of VFD equipment, ensuring it operates reliably.

Avoiding Costly Downtime
Downtime in industrial processes can result in significant financial losses. When VFD equipment fails due to surges, production grinds to a halt. TPD surge protection helps prevent these failures, ensuring continuous operation and minimizing downtime-related costs.

Maintaining Process Efficiency
VFDs are often used to control critical processes, such as HVAC systems, conveyor belts, and manufacturing lines. Any disruption in VFD operation can impact process efficiency and product quality. TPD surge protection maintains the stability of VFDs, ensuring that processes run smoothly and products meet quality standards. Today, VFDs are also found in residential HVAC systems.

Preventing Data Loss
Some VFDs are equipped with advanced monitoring and control features, and they may store valuable operational data. Surge-induced failures can result in data loss, which can be both costly and detrimental to troubleshooting and performance analysis. TPD surge protection safeguards against data loss by preventing equipment damage.

Extending Equipment Lifespan
VFDs are long-term investments for industrial facilities. Replacing damaged VFDs prematurely can be a substantial financial burden. TPD surge protection helps extend the lifespan of VFD equipment, reducing the frequency of replacements and associated costs.

Compliance and Safety
In certain industries and applications, compliance with safety standards and regulations is mandatory. TPD surge protection can help meet these requirements, ensuring safe and reliable VFD operation and minimizing risks to personnel and equipment.

Environmental Considerations
VFDs are often used to control motors in energy-efficient systems. Equipment failures due to surges can lead to increased energy consumption, which is not only costly but also less environmentally friendly. TPD surge protection helps maintain energy-efficient operations and sustainability goals required for LEED certification.


Financial Costs and Life Cycle Savings

The cost and repair of a single surge event or two at most will typically pay for the price a TPD VFD surge protector. Although labor costs vary, having a specialized technical person show up with parts and pay for travel will have a minimum charge of $500 to $1500 on average. This means, for a small upfront investment, our surge suppressor products will lead to enormous life cycle savings!


Surge Suppression for VFDs 

VFDs are very common in industry and can provide many years of reliable service. Unfortunately, one of the major causes of VFD failure are electrical surges. From no detectable effect to complete destruction, the effects on equipment can be many. Fortunately, there are surge protection devices (SPDs) on the market that can provide protection for your VFDs. By definition, an electrical surge is a transient electrical voltage or current that occurs in an electrical circuit. Typically, a power surge is an oversupply of electrical voltage from a variety of sources. Sometimes these surges come from the electrical utility, due to switching or equipment failure. Other times, they come from an internal surge from equipment inside the facility. Sometimes, the problem is a lightning strike. What kind of damage can a surge do to your VFD? In a word, catastrophic. The front end of a typical drive consists of a semiconductor diode bank. These diodes convert the AC line voltage to a DC voltage and severe overvoltage will destroy these devices. Recently, a massive electrical storm in Illinois destroyed multiple drives in a manufacturing facility. While the cost to replace these drives was a somewhat reasonable figure, the subsequent downtime ran into the hundreds of thousands of dollars. (Written by Jim Davis, Automation Engineer)


PDF – VFD – Nursery Case Study. ROI met in only a few months.
PDF – VFD – Reduced troubleshooting time & lost production. 40% reduction in electrical maintenance.