Harmonic filters are electrical power quality solutions used to reduce harmonic distortion caused by non-linear loads. In many facilities, harmonics are commonly generated by equipment such as Variable Speed Drives, soft starters, rectifiers and other power electronics.

When harmonics are not properly controlled, they may contribute to:

• Overheating of cables, transformers and electrical components
• Nuisance tripping of breakers or protection devices
• Reduced equipment lifespan
• Distorted current waveform
• Inefficient use of electrical system capacity
• Increased maintenance concerns
• Power quality compliance issues

A properly selected passive harmonic filter helps reduce unwanted harmonic currents and supports smoother, more stable operation of connected equipment.

Interwell offers Schaffner passive harmonic filters, including the Passive Filter THDI<5% range. Schaffner ecosine harmonic filters are designed as an economical solution for mitigating load-applied harmonics in three-phase power systems.

The compact, plug-and-play approach makes these filters suitable for installations where quick commissioning, dependable performance and efficient use of panel space are important.

Product Snapshot

• Brand / Model: Schaffner / 3440
• Rated Current: 60A per module
• Supply Voltage: 3 Phase 380–500V
• IP Rating: IP20
• Applications: Fans, pumps, compressors, conveyors
• Suitable Segments: HVAC, industrial, water & wastewater
• Certificates: CE, ROHS, UL

For correct product selection, Interwell can assist with reviewing your application, drive rating, load type and installation requirements.

Variable Speed Drives are widely used across Singapore for motor control, energy efficiency and process optimization. However, drive-based systems can introduce harmonic distortion into the electrical network.

This is especially important for systems involving:

• HVAC fans and chilled water pumps
• Booster pumps and circulation pumps
• Compressors
• Conveyors
• Industrial motor control systems
• Water and wastewater facilities
• Building services and facility management systems

By integrating a suitable harmonic filter with Variable Speed Drives, businesses can help reduce distortion, protect electrical infrastructure and support smoother long-term operation.

Suitable for Key Commercial & Industrial Applications
The Schaffner Passive Filter THDI<5% range is suitable for common applications such as fans, pumps, compressors and conveyors.

Compact, Practical and Easy to Commission
The plug-and-play design supports faster installation and commissioning compared with more complex mitigation solutions.

Interwell Pte Ltd is a Singapore-based supplier with experience across power quality products, Variable Speed Drives, soft starters and EV charging solutions. The company supports customers who need practical, technically suitable products for real operating environments.

Established Technical Product Experience
Interwell works with power electronics, drive systems and power quality products, making it well positioned to support customers selecting harmonic filters for drive-related applications.

Schaffner EMC Power Quality Product Range
Interwell supplies Schaffner harmonic filter solutions for customers who need reliable harmonic mitigation in Singapore.

End-to-End Service Support
From supply and delivery to installation, commissioning, maintenance and replacement, Interwell provides support throughout the product lifecycle.

Singapore-Focused Support
For local facilities, contractors and consultants, working with a Singapore-based supplier allows faster communication, clearer coordination and easier technical follow-up.

Interwell’s harmonic filter solutions are suitable for a wide range of local applications, including:

• Commercial buildings
• HVAC systems
• Industrial facilities
• Manufacturing plants
• Water and wastewater systems
• Pump control systems
• Compressor systems
• Conveyor systems
• Building services applications
• Facilities using Variable Speed Drives

Whether you are upgrading an existing electrical system or planning a new project, Interwell can help recommend a suitable solution based on your application.

What are harmonic filters used for?
Harmonic filters are used to reduce harmonic distortion in electrical systems caused by non-linear loads such as Variable Speed Drives, rectifiers and other power electronics.

Do Variable Speed Drives need harmonic filters?
Not every installation requires the same level of harmonic mitigation, but many systems using Variable Speed Drives can benefit from harmonic filters, especially where power quality, equipment reliability or compliance is a concern.

What applications are Schaffner passive harmonic filters suitable for?
Schaffner passive harmonic filters are suitable for applications such as fans, pumps, compressors and conveyors, commonly used in HVAC, industrial and water-related systems.

What does THDI<5% mean?
THDI<5% refers to Total Harmonic Distortion of Current being reduced to below 5% under suitable operating conditions and correct product selection.

Can Interwell help with installation and commissioning?
Yes. Interwell supports supply, delivery, installation, commissioning, maintenance, repair and replacement for the products it offers.

How do I request a quote?
You can contact Interwell through WhatsApp and share your application details, including drive rating, voltage, load type and quantity required.