Mirus International

Harmonic and Energy Saving Solutions


MIRUS International Inc. designs and develops world class power quality improvement products for mission critical operations. Our specialized product line includes highly efficient harmonic filters, transformers, autotransformers and Data Center power distribution equipment. Mirus’ solutions minimize disruption to the power supply, improve reliability and adhere to the strictest of regulatory requirements while also saving energy and reducing operating costs.

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Oil and Gas
Water and Waste
Data Centers
Lineator Harmonic Filter

Lineator AUHF

Advanced Universal Harmonic Filter

The LINEATOR™ Advanced Universal Harmonic Filter (AUHF) is a revolutionary advancement in the area of passive harmonic mitigation. No other device on the market can meet the stringent limits of IEEE Std 519 at an equivalent efficiency, size and cost. When your application calls for a truly cost effective harmonic solution, the LINEATOR AUHF is the logical choice. It provides Engineers with a standard off-the-shelf solution for what used to be a very challenging engineering problem.

The LINEATOR is a purely passive device consisting of a unique inductor combined with a relatively small capacitor bank. It’s innovative design achieves reduction of all the major harmonic currents generated by VSD’s and other similar 3-phase, 6-pulse rectifier loads. The resulting ITHD is reduced to <8% and and is now available in a model that achieves <5%. Although referred to as a filter, the LINEATOR exhibits none of the problems that plague conventional filters.


Lineator HP

Lineator HP

High Performance LINEATOR™

The Lineator High Performance (HP) model is used where the highest power quality demands must be met. Lineator HP outperforms active filters in efficiency, with gains of 2 per cent or more. It is more reliable and easier to maintain than any of the complex AFE drives or active filters currently available.

Specifying the Lineator HP for applications with standard 6-Pulse ASD’s provides end-users with low harmonic drive systems at 20 to 30 per cent less in capital costs than other solutions. Operating costs are also significantly lowered due to the higher efficiency gains.

In addition to all the benefits of the Lineator AUHF, the new High Performance HP model offers < 5% ITDD. With the addition of a tap to allow for reactor impedance adjustment, current distortion levels of < 5% can be achieved without introducing excessive voltage drop or ASD instability.


Lineator ED

Lineator ED

Extreme Duty LINEATOR™

For extreme environments, such as excessive background voltage distortion (5% to 12% VTHD), high ambient (up to 55º C) or high elevation (above 3000 ft), Mirus now offers an extreme duty model for its Lineator AUHF. Our standard Lineator AUHF already outperforms any other competitive filter by guaranteeing performance when background voltage distortion is as high as 5%. In some applications however, such as marine vessels, drilling rigs and oil fields equipped with electrical submersible pumps (ESP’s), existing voltage distortion levels will often exceed 5%. Also, when ambient temperature levels exceed 40º C or at higher elevations where the air is thinner, a more robust filter is required. The Lineator-ED model will meet this challenge.


Lineator ATL

Lineator ATL

Low Voltage AutoTransformer with LINEATOR™ Harmonic Filter

The use of 6-pulse Variable Speed Drives and other static power conversion equipment has grown rapidly in recent years. With this growth has come concern over the level of current harmonics generated by such equipment. Harmonic currents and the voltage distortion these currents create can have devastating effects on a power distribution system and its connected equipment. Present methods of harmonic treatment on low voltage 6-pulse VFD applications where the VFD voltage rating is different from the service voltage, require a special replacement 18-Pulse VFD, or a separate transformer to match the existing 6-Pulse VFD voltage along with tuned passive filters, or expensive active filters. The innovative AutoTranslineator™ is the best advance in the area of low voltage passive harmonic mitigation available today. No other device on the market can meet the limits of IEEE STD 519 at an equivalent size, efficiency and cost. When the application calls for harmonic treatment for low voltage 6-pulse VFD applications where the VFD voltage rating is different from the service voltage, the AutoTranslineator™ is the only logical choice.


Lineator 1Q3

Lineator 1Q3

Passive Harmonic Filter for 3-phase VFD’s Operating on a 1-phase supply

In remote locations such as farms, golf courses, oil and gas fields and residential areas standard 3-phase Variable Speed Drives are often used as Phase Converters to supply 3-phase motors when only 1-phase power is available. The Lineator™ 1Q3 is ideal for systems such as water and waste water, pump jacks, irrigation and many others.

The Lineator-1Q3™ has been designed to address this application by accepting 1-phase input and supplying a quasi 3-phase supply to the VFD. This will significantly lower both input harmonic current distortion (by up to 10x) and DC ripple current within the VFD. Reducing the ripple current allows for less derating of the VFD which, in many cases, will offset the cost of the Lineator-1Q3™.


MOS - Lineator

MOS Lineator™

Marine and Offshore Specific Lineator

The Mirus Lineator wide spectrum passive harmonic filter, a well proven method of mitigation in offshore and marine environments, still remains the best technical solution to treat harmonics. It not only addresses all requirements to meet full compliance of certifying body harmonic distortion ‘rules’ worldwide, it is guaranteed to outperform all other passive and active solutions. The Lineator is now available in a hardened version specifically designed for severe marine and offshore applications.


Lineator can be maintained ‘on the run’

The Marine & Offshore Specific Lineator can be optionally configured for service and maintenance of the capacitors without powering down the reactor. A circuit breaker isolates the capacitor bank which is compartmentalized for safe access by qualified electrical staff. The system can temporarily operate on the reactor alone with reduced harmonic mitigation. This eliminates operational shut-downs thus ensuring your main propulsion, drilling operation and production is always up and running.

Note that even with all capacitors disconnected, the performance of the Lineator reactor alone will be as good as a 12 pulse system so it “will get you home” every time.
Marine & Offshore Specific Construction
  • Fortified IP rated enclosure built for ‘real world’ marine environments.
  • Ambient ratings through 50ºC nominal
  • Two-part Marine grade powder coat
  • Galvanneal paneling
  • Tin plated terminals
  • Internal bracing for vibration and shock resistance
  • Stainless steel hardware
  • Conformal coating on capacitors and electronic components for humidity resistance and corrosion protection
Features and benefits:
  • High Performance Lineator Modelachieves <5% Ithd (THDi) at rated load
  • Overvoltage and overcurrent detection
  • Capacitor monitoring
  • Condition based monitoring with automatic capacitor disconnect
  • Voltage and current waveform sampling
  • Programmable alarm setpoints
  • Web based access via browser
  • Assignable digital inputs and relay outputs
  • Temperature thermocouple monitoring
  • IP23 [Nema 3R], IP24, IP25, IP44 or IP45 Enclosure
  • Second meter for harmonic mitigation performance and power measurements
  • Local touchscreen display
  • Capacitor section isolation for capacitor replacement ‘on the fly’
  • Capacitor switching contactor for multiple generator applications where capacitive reactance capability is low
  • Water cooling to minimize footprint
Note: Lineators are 12-15% kVAr compared to 28-40% kVAr for competitive filters. Lineators therefore do not normally require capacitor switching on generator derived supplies.


Inversine - Advanced Universal Sine-wave Filter


Advanced Universal Sine-wave Filter

High dV/dT combined with a mismatch between cable and motor surge impedance can result in reflective wave phenomenon at standard induction motor terminals. Voltages can increase by as much as 2 to 3 times nominal peak levels possibly exceeding the insulation rating of the feeder cables and motor magnetic wire leading to insulation stress, partial discharges and eventual failure. This problem can result with short cable runs but becomes magnified with long cable runs.


Typical problems experienced can include motor and winding failure, motor noise, cable insulation degradation, premature ASD failure, common-mode and reflected wave phenomenon and high EMI/RFI.

Differential Mode

The Inversine Advanced Universal Sine-wave Filter (AUSF) is designed to address the problems resulting from pulse width modulation. It is a low pass filter with cut-off frequency well below the switching frequency of the inverter.

The AUSF is much more than a simple dV/dT filter and will:
  • Substantially reduce voltage rise time (dV/dt)
  • Convert output voltage to near sinusoidal waveform (<3%)
  • Prevent transient overvoltages at motor terminals
  • Lower harmonic losses in the motor
  • Reduce motor noise
  • Reduce motor and cable insulation stress
  • Extend life of the motor and ASD

Common-mode is the phase-to-ground voltage that appears as a result of the instantaneous sum of the 3-phase voltages of the PWM inverter not being zero even when the sum of the average 3-phase voltages is zero. Common-mode voltages will induce common-mode currents to flow through parasitic capacitance in the motor and motor feeder cable. High frequency capacitive coupling exists across the motor bearings and between the feeder conductor or motor winding and ground. Common-mode currents can lead to premature motor bearing failure.

The Inversine Common-mode Filter option will:
  • Reduce shaft voltage and bearing currents
  • Reduce cable leakage currents
  • Reduce common-mode voltages throughout power system
  • Lower harmonic losses in the motor
  • Low insertion loss and voltage drop(<2% of rated voltage)
  • No damping resistors required
  • Power delivered to motor >96%
  • Efficiency >98%
  • Improves Power Factor of the motor near unity
  • Reactive power compensation
  • Prevents transient overvoltages at motor terminals
  • Reduces motor noise
  • Filters out high frequency currents while allowing lower fundamental currents to pass
  • Reliable and proven performance


Dissimilar Pitch Neutral Limiter

GENLINK DPNL is a multiple winding reactor that, when installed in the common neutral of paralleled sources either between the dissimilar generators or the generator and the utility supply, can greatly reduce the neutral circulating currents that result from the instantaneous voltage differences. These neutral circulating currents, which are predominantly triple frequency, have the potential to cause a considerable amount of damage with respect to overheating generators and causing false-protection trips.

Voltage differences in paralleled generators made by different manufacturers or differences in standard pitch design configurations in generators made by the same manufacturer can result in heavy neutral circulating currents. Additionally, alternative energy sources such as solar and wind power that generate AC power can introduce heavy circulating currents in 4-wire parallel applications. When applied, GENLINK will impede the flow of circulating currents while adding only minimal impedance to the fault current path.

GENLINK DPNL can be used in both 3-wire and 4-wire systems. For 4-wire applications where there is return neutral current from 1-Ph loads, the DPNL must be sized for this current as well as the circulating current. For 3-wire applications where there is no return neutral current from 1-Ph loads, a smaller size DPNL can be used. Grounding of the neutral must be done at only one location, which is recommended to be the distribution switchboard.

  • Inserts >40% impedance in neutral current circulating path
  • Reduces neutral circulating current by >75%
  • Adds <1% saturated impedance to 1-Ph fault path
  • No impedance to 3-Ph fault path
  • Use in 3-wire or 4-wire applications or any parallel source application with a common neutral and dissimilar voltage waveforms
  • Eliminates generator overheating and false protection trips caused by triple frequency circulating currents
  • Easy to install
  • Reliable and proven performance


High Efficiency Transformers

ULLTRA High Performance transformers are designed to deliver more energy savings than any other transformer on the market. The result is a high performing transformer that offers the highest efficiency in the industry under either linear or non-linear loading and maintains these high efficiency levels at not only 35% loading, but over the entire load range.

While other energy efficient transformers on the market may meet new, more demanding standards such as NEMA Premium and CSL3, these standards only restrict losses under linear loading and at 35% load levels. When it comes to higher load levels and non-linear loading, other transformers on the market can’t offer the same high efficiencies under these conditions. ULLTRA High Performance transformers actually exceed NEMA Premium efficiency levels at their peak performance loading of 50%, thereby assuring the most energy savings under any loading.


ULLTRA High Performance Transformers offer quicker payback periods, and are engineered to perform. All ULLTRA Transformers are real-world tested in Mirus’ Harmonics & Energy Lab.


A perfect solution for any application where energy efficiency and lower life cycle costs are critical – K-12 and Higher Education, Government, Healthcare, Broadcasting, Commercial, Industrial and LEED buildings. Applications that expect heavier loads such as Data Centers, Solar and other Alternative Energy projects, will benefit from the ULLTRA Series Transformers’ ability to maximize savings under ANY load and for ANY load profile.


ULLTRA™ – Ultra Low Loss Transformer

  • Optimized for any load level making ULLTRA the only transformer ideally suited for both light or heavy loading conditions
  • Linear load losses are a full 30% lower than the already low levels defined by NEMA TP-1
  • Efficiencies meet NEMA Premium levels at the mandated 35% loading and even exceed these levels at the transformer’s peak design loading of 50%
  • Harmonic losses are also reduced to ensure efficiencies meet NEMA TP-1 requirements even under ‘real world’ non-linear loading
  • Inrush currents (< 8x rated) and audible noise (3dB lower than standard) are extremely low
  • Ideal for Solar Power or other applications where transformer loading varies widely and electricity rates are high

ULLTRA-H1E™ – Harmonic Mitigating Transformer

In applications where non-linear loading is expected to be severe, the ULLTRA-H1E combines the proven harmonic mitigating properties of Mirus’ Harmony™ HMT line with superior energy efficiency, low inrush, and low audible noise found in the ULLTRA design.

  • Voltage distortion (flat-topping) is minimized by cancelling zero sequence fluxes within the secondary windings and eliminating circulating currents in the primary windings
  • Treats triplen harmonics (3rd and 9th) within the transformer and 5th and 7th upstream
  • The highest efficiency harmonic mitigating transformer from the company that first introduced HMT’s to the market in the early 1990’s
  • Highest efficiencies in the industry at any load profile and at all load levels
  • Lowest ‘Life Cycle Costs’ for best paybacks and improved bottom line
  • Improves reliability by reducing voltage distortion
  • Exceeds CSL-3 and NEMA Premium requirements in a wider load range
  • Exceeds NEMA TP-1 efficiencies under non-linear loading
  • Energy savings are realized even during peak load conditions when environmental impact is greatest
  • Lower losses minimize energy waste and protect the environment by reducing greenhouse gas emissions
  • Contributes to LEED (Leadership in Energy Efficient Design) in Energy & Atmosphere and Innovation & Design categories
  • Performance validated through linear and non-linear load testing in Mirus’ Harmonics & Energy Lab
  • Inrush magnetization currents are the lowest in the industry
  • Lower audible noise levels: 3dB to 5dB below NEMA ST-20 requirements
Harmony™ Series Transformers

Harmony™ Series Transformers

HARMONY™ SERIES isolation transformers and autotransformers combine very low zero sequence impedance outputs with phase shifting for effective harmonic mitigation. They are designed to replace standard or k-rated transformers, especially when servicing single phase (120V L-N) non-linear loads, such as personal computers and other power electronic equipment.



NEMA STD TP1 Compliant Harmonic Mitigating Isolation Transformers with low zero sequence impedance secondary windings. Available with either 0° or 30° phase shift between primary and secondary windings.

Configuration of the secondary windings cancels the fluxes generated by the triplen harmonics in the load current thereby minimizing triplen harmonic voltage distortion. Choice of phase shift permits cancelling of 5th and 7th current harmonics against those of other loads fed from the same primary supply.

Harmony-2E™ and Harmony-3E™

NEMA STD TP1 Compliant Multiple output phase shifting transformers with extremely low zero sequence impedance (patented). Available in both isolation or autotransformer configurations.

All models have secondary windings which cancel the triplen harmonic fluxes to minimize triplen harmonic voltage distortion. 5th, 7th and other higher order harmonics are cancelled as well to further reduce heating, voltage distortion, and upstream harmonic currents.

Harmonics treated by the secondary windings are as follows:

Harmonic No. Product
3rd, 5th, 7th, 9th, 15th, 17th Harmony-2™*
3rd, 5th, 7th, 9th, 11th, 13th Harmony-2™
* pairs of Harmony-2™ transformers can be configured to treat 11th & 13th on the primary bus.

The impedance of standard or K-factor transformers will often introduce anywhere from 5-15% voltage distortion when servicing non-linear loads. Multiple output Harmony™ transformers will typically add only 1-3% voltage distortion when servicing similar non-linear loads.

Eliminator™ Series

Eliminator™ Series

Low Zero Sequence and Phase Shifting Autotransformers


Neutral Current Eliminator™ (NCE™)

A 3-phase, low zero sequence impedance autotransformer, which when connected near to and in parallel with the harmonic generating non-linear loads (usually connected at the distribution panel), provides an alternate path for 3rd, 9th, & 15th current harmonics (triplens) which the loads create. Patented Field Adjustable Impedance (FAI) feature allows for adjustment of NCE™ zero sequence impedance to field conditions.

Reduces neutral current and neutral-to-ground voltage as well as both current and voltage triplen harmonic distortion.

Combined Neutral Current Eliminator™ (CNCE™)

A patented phase shifting autotransformer with a low zero sequence impedance at its output. When connected in series on a 3-phase, 4-wire service to non-linear loads, it provides an alternate path for the triplen harmonics. The CNCE™ also phase shifts 5th and 7th current harmonics by 180º so that they cancel with 5th and 7th harmonics from other loads on the distribution system. Optional FAI feature allows for removal of triplens from the CNCE™ input side as well as secondary.

Reduces neutral current, and neutral-to-ground voltage, as well as both current and voltage harmonic distortion at 3rd, 5th, 7th, & 9th harmonics.

5-7, 11-13 and 5-13 Eliminators™

3-phase, 3-wire autotransformers with 30°, 15° or 20° phase shift between input and output. They are connected in series with the supply to variable frequency drives, UPS systems, and other 3-phase rectifier loads.

By phase shifting against other similar loads, they reduce 5th and 7th or 11th and 13th harmonic currents at point of common coupling which, in turn, reduces voltage distortion as well.

  • Diverts the flow of harmonic currents away from neutral and upstream transformer
  • Reduces high neutral current and neutral-to-ground voltage
  • Eliminates the need for doable ampacity neutrals upstream
  • Reduces losses and lowers operating temperature in upstream distribution transformer
  • Substantially reduces primary winding circulating currents in distribution transformers
  • Reduces current distortion at UPS, generator or Utility service
  • Saves energy by reducing harmonic losses
  • Prevents voltage flat-topping caused by non-linear loads
  • Lowers voltage distortion to prevent premature equipment failure
  • Restores ride-through capability of computer equipment
  • Improves Power Factor
  • Integrated ammeter measures neutral current removed
  • Field adjustable impedance option offers improved application flexibility
  • Helps meet IEEE Standard 519 harmonic limits
Drive™ Series Transformers

Drive™ Series Transformers

Phase shifting isolation transformers and autotransformers designed to produce cancellation of the characteristic harmonics of 3-phase rectifiers to produce effective 12-pulse 18-pulse, and 24 pulse schemes.


Drive Tamers™

Designed to replace standard drive isolation transformers, the Drive Tamer™ is built to not only withstand the harsh harmonic environment produced by Variable Frequency Drives (VFD), but to also induce cancellation of harmonics upstream and thereby reduce voltage distortion throughout the distribution system.

By alternating 0° phase shifting models with 30° models, 5th and 7th harmonics are cancelled upstream. Where 3 loads are being serviced +20° , 0° , -20° models can reduce 5th, 7th, 11th and 13th harmonics, thereby dramatically reducing the voltage distortion these harmonics produce.

Drive 12/24™, Drive 18™ & Drive 24™

Multiple output auto or isolation transformers ideally suited for reduction of harmonics generated by VFDs or other 3-phase rectifier loads.

Drive 12/24™ produces a 12 pulse scheme (cancellation of 5th and 7th) when servicing two 6 pulse drives. A 24 pulse scheme is produced upstream (cancellation up to 23rd harmonic) when multiple Drive 12/24™ are used. Drive 18™ are used when servicing three 6 pulse drives to produce an 18 pulse scheme. The Drive 24™ will produce a 24 pulse scheme when servicing 4 drives. Each of these configurations will substantially reduce voltage distortion on the distribution system.



Harmonic Analysis Software

SOLV™ is a powerful simulation program that will calculate current and voltage distortion levels by simulating the Mirus Lineator™ and Variable Speed Drive (VSD) / Variable Frequency Drive (VFD) based on your load requirement. By simply entering some basic information about your source and VSD system, MIRUS’ SOLV™ will help you find the right solution for your VSD application by accurately predicting the performance level you can expect without the need of a costly harmonic study. You can download SOLV™ for free – download now!

SOLV™ also allows you to perform energy analysis by providing evidence of how energy can be saved by removing harmonic losses introduced by VFDs and justifying the use of Lineators based on energy savings. Its kW calculation includes all harmonic losses in transformers and cables and provides total kW, kVA and kVAR at the Point of Common Coupling (PCC), Distribution Panel in the Summary Report. SOLV™ eliminates the guesswork in evaluating the best performing solution for your harmonic challenges.

This software is a valuable tool for consulting and specifying engineers, utility operators, OEMs and anyone who needs to evaluate and compare solutions for treating harmonics in VFD applications. A trusted tool since 2004, SOLV™ is used by power quality professionals that represent a wide spectrum of industries including Oil & Gas, Marine, HVAC, Water/Wastewater, Industrial, Government, Education, to name a few.

  • Friendly, easy-to-use
  • System and load parameters are entered with a simple one-line diagram editor
  • Built in library contains all Lineator™ AUHF filters and load models for alternate solutions
  • Powerful Simulation Engine provides fast and accurate analysis
  • Harmonic voltage and current distortion evaluation (THD & IHD)
  • Calculates Telephone Interference Factor (TIF) and I*T Product
  • Performs energy analysis
  • View onscreen Waveforms, Spectrum and Phasor diagrams
  • Report tool provides detailed IEEE 519 compliance, harmonic distortion and TIF reports
  • Ability to Export Harmonic Spectrum data to a spreadsheet
  • Units can be set to Imperial or Metric
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