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Protecting mission-critical operations from damage, downtime and danger
HarmonixThe world's first cost-effective active harmonic cancellation filter. From Current Technology, the leading name in electrical power reliability for more than three decades.

At last, a well-engineered solution to the myriad problems created by excessive harmonic current: the Harmonix active cancellation filter from Current Technology. Developed in collaboration with faculty electrical engineers from Texas A&M University and extensively beta-tested at mission-critical customer sites, the patented Harmonix expertly handles the constantly changing harmonic currents inherent in today's busy facilities.

Unlike the passive harmonic cancellation devices of yesterday, the flexible Harmonix is easy to upgrade and automatically adapts to all changing facility loads. Harmonix models provide effective filtering without forming a resonant circuit with the source impedance. The result: as much as 200% more cancellation than "passive" harmonic technologies.

Retrofit or build-out: Harmonix eliminates costly, dangerous problems to ensure uptime and worry-free operation

Engineered for fast and simple installation in existing or new facilities, the proven, patented Harmonix is connected in parallel with the building's power network to eradicate all zero-sequence harmonics from the phases and neutral upstream in the distribution system, thereby safeguarding mission-critical equipment from:
    overheating of transformers, neutrals and connectors

    waveform distortion
    destruction of computer components
    burned relay contacts

    equipment malfunction
    blown fuses
5 Best Products of '98!     low power factors
    increased energy costs

    breaker tripping
    motor overheating

    increased ground potential
    high voltage differentials

From air traffic control towers to wastewater treatment plants: Harmonix' superior features and benefits actively safeguard mission-critical environments

Backed by more than a quarter-century of Current Technology's legendary power reliability product innovation, maintenance-free Harmonix models are stackable and parallelable for easy upgrade and expansion. Each factory-tested Harmonix model includes the following standard features and benefits:
    100 amp harmonic cancellation current
    active filtering of no less than 90% of all harmonic neutral currents
    cancels triplen phase harmonics (3rd, 9th, 15th)
    load-independent/active neutral current monitoring

    stand-alone modular design
    meter switch for triplen and total RMS current monitoring

    maximum cancellation current light
    pulse-by-pulse current limit protection
    thermal shutdown protection and indication light
    pass-through ports for easily upgradeable interconnection

    alarm bypass and indication light
    control panel battery backup/low battery indication light

    digital LCD neutral current and cancellation current meters
    form "C" dry contacts for easy connection to building management system
    control panel test switch to verify monitoring circuit integrity

    Three Year Product Warranty
    "24x7" around-the-clock Technical Hotline

What are harmonics?
The technical definition of a harmonic is "the sinusoidal component of a periodic wave or quantity having a frequency that is an integer multiple of the fundamental frequency." In music, harmonics are the overtones that distinguish the sound of one stringed or woodwind instrument from another by producing complex sounds. Similarly, electrical harmonic currents produce waveforms that may be broken into components. When a current sine wave is not proportional to the electrical systems' voltage, harmonics are present. Harmonic frequencies are integer multiple of the fundamental frequency.

How do harmonics damage electrically powered equipment?
Harmonic currents travel from the load through the electrical system and onto the power source. The amount of harmonic voltage and current that a system will tolerate is dependent upon both the load and the source. The continuing proliferation of single-phase nonlinear power electronic loads guarantees that damaging harmonic disturbances will only increase as equipment operation becomes faster and more sophisticated.

How does the Harmonix active cancellation filter work?

Harmonix active harmonic cancellation filters Harmonix inside...eliminate no less than 90% of harmonic neutral currents via an exclusive, patented engineering process. Neutral currents are sensed by a current sensor and processed through a notch filter to eliminate the fundamental component of the neutral current signal. This error signal is then amplified and modulated to generate full-bridge inverter gating signals. The inverter then actively injects an equal and opposite current to rapidly deliver closed-loop active cancellation.

Why is "active" harmonic filtering superior to passive technologies?
Some of the advantages of active harmonic filtering include performance independent of system impedance, cancellation of zero-sequence harmonics by measurement and closed-loop control, built-in current limit (no overloading), fast-response characteristics and sufficient bandwidth to cancel zero-sequence harmonics, smaller footprint, and stable operation. Harmonix is the only technology that provides guaranteed performance values regardless of phase balance, loading, or connection distances (within recommendations). As loads and distribution systems change over time, Harmonix performance characteristics do not degrade.

Harmonix cancellation is determined by the sensing circuit at the point of connection. This eliminates the possibility of the active device drawing harmonics from other locations in the distribution system and potential filter overloading. But the most important differences are the extremely high cancellation efficiency of the Harmonix' active technology, which delivers as much as 200% more cancellation than passive devices, the Harmonix' ability to handle changing currents, easy upgradability and long-lasting, reliable protection.
Ask an Engineer if you have any questions regarding this or other Current Technology products.


For more information about these or any other surge protection products or to speak with one of our sales reps, please contact us.

Tel: 407-380-9200 Fax: 407-380-3911 Email: jwest@psihq.com

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