Line-side conditions
Supply voltage, available fault current, transformer size, existing capacitors and harmonic limits influence line-reactor and filter choices.
Drive-system protection and compliance
Power Quality Products for VFD Installations
Match reactors, filters, braking components and protection to the actual drive system. We support accessory selection for supply harmonics, long motor cables, EMC concerns, regenerative energy and difficult electrical environments.
- Line- and load-side accessories
- Drive, motor and installation reviewed together
- Replacement and project-list sourcing
Selection foundation
The correct accessory depends on where the problem occurs.
A line reactor addresses different conditions from a load reactor, sine-wave filter or harmonic filter. Braking resistors handle regenerated energy during deceleration, while EMC filters address conducted emissions. Selecting by drive kW alone can produce incorrect impedance, current, voltage or thermal ratings. The one-line diagram, drive model, motor cable length, switching frequency and performance objective provide a much better starting point.
Motor cable and insulation
Cable length, motor voltage, insulation age and switching frequency help determine whether a load reactor, dV/dt filter or sine filter is appropriate.
Braking duty
Deceleration time, load inertia, cycle frequency and regenerated energy determine braking resistance, power and thermal duty.
Compliance objective
Define the required harmonic, EMC or motor-terminal performance and the applicable standard instead of requesting a generic filter.
Product range
Product types within this category
These groups are a practical way to narrow the requirement. Final model selection still depends on the electrical, mechanical and installation data shown on this page.
AC line reactors
Input-side impedance used to moderate current waveform, supply disturbances and peak charging current under appropriate system conditions.
Typical fit: Drive inputs on stiff or disturbed electrical supplies
Load reactors
Output-side reactors applied to moderate motor-terminal waveform effects and support selected motor-cable installations.
Typical fit: Moderate cable extensions and motor protection support
dV/dt and sine-wave filters
Output filters with different degrees of waveform conditioning, losses, size and operating constraints.
Typical fit: Long cables, older motors and defined waveform limits
Passive and active harmonic filters
System solutions selected from drive load, network impedance, background distortion and the required measurement point.
Typical fit: Projects with documented harmonic-performance targets
EMC and RFI filters
Conducted-emission components coordinated with the drive, grounding, cable shielding and installation category.
Typical fit: Installations with defined electromagnetic-compatibility requirements
Braking resistors and units
Dynamic-braking components sized from minimum resistance, regenerated energy, stopping time and cycle frequency.
Typical fit: Rapid deceleration and non-continuous regenerative duty
Quick selection
Identify the installation condition
Select what is known and send the drive model or one-line diagram after WhatsApp opens. Unselected fields are not required.
Typical specification scope
What we can match
- Input-side products
- Line reactors, chokes and harmonic solutions
- Output-side products
- Load reactors, dV/dt and sine-wave filters
- EMC products
- Conducted-emission filters by drive and installation
- Braking products
- Resistors, braking units and regenerative options
- Selection data
- Voltage, current, frequency, impedance and duty
- Supply formats
- Loose component, enclosure or panel-integrated package
Common applications
Where selection changes with the load
Weak or disturbed supplies
Line impedance, notching and transient exposure are reviewed before adding reactors or other input-side protection.
Long motor cables
Cable length, motor insulation and allowable motor-terminal waveform guide the choice of load reactor, dV/dt or sine filter.
Fast stopping and overhauling loads
Cranes, centrifuges, conveyors and high-inertia machines may need dynamic braking or a regenerative drive solution.
Harmonic and EMC projects
Target limits, measurement point, system impedance and the total drive load are defined before a compliance solution is selected.
Decision guide
Choose the right product path before comparing models
Line reactor
- Choose when
- Additional input impedance is useful and the objective does not require a dedicated harmonic filter.
- Verify before ordering
- Current, inductance, voltage drop, enclosure and interaction with the supply.
Load reactor or dV/dt filter
- Choose when
- Motor cable length or voltage rise needs more output conditioning than the base drive installation provides.
- Verify before ordering
- Cable length, motor insulation, carrier frequency, output current and manufacturer limits.
Sine-wave filter
- Choose when
- The application needs a substantially sinusoidal motor-side waveform for a documented reason.
- Verify before ordering
- Fundamental frequency range, voltage drop, losses, resonance and allowed motor control mode.
Harmonic filter or low-harmonic drive
- Choose when
- A project specifies current-distortion performance at a defined electrical point.
- Verify before ordering
- Load schedule, transformer, fault level, background distortion and compliance calculation.
From requirement to quotation
A short path to a verifiable product match
Define the observed problem
Share the drive model, system voltage, motor cable, one-line diagram and the symptom or compliance target.
Locate the electrical cause
Input conditions, output waveform, braking energy and installation layout are separated so the right product class is considered.
Confirm ratings and installation
The proposed component is checked for current, voltage, impedance, thermal duty, enclosure and connection location.
Frequently asked questions
Practical answers before you request a quote
What is the difference between a line reactor and a load reactor?
A line reactor is installed on the input side of the VFD and can add impedance against supply disturbances while reducing current distortion. A load reactor is installed between the drive and motor, commonly to moderate output waveform effects and support longer cable runs.
When is a dV/dt or sine-wave filter considered?
These filters may be considered for long motor cables, older insulation, sensitive motors or applications with waveform limits. A sine filter provides stronger output smoothing but has different size, loss and operating constraints than a dV/dt filter.
How is a VFD braking resistor selected?
Selection uses the drive manufacturer’s minimum resistance plus the load inertia, speed change, stopping time and cycle frequency. Both resistance and power or energy duty must be correct, and the resistor needs safe mounting and thermal protection.
Will a line reactor make a VFD IEEE 519 compliant?
Not automatically. IEEE 519 evaluation is made at the point of common coupling and depends on the complete system. Meeting a project limit may require system data, harmonic calculations or measurements and a dedicated filter or low-harmonic drive solution.