Hammond Power Solutions RM SERIES Features and Benefits

SECTION 3

RM SERIES

Why Choose A Line Reactor?

Utilizing variable speed drives to control motor speed has impacted industry both in energy savings and

increased efciencies. The challenge for today’s designers is dealing with non-linear wave shapes generated by

solid state devices.

By choosing a HPS line reactor, many line problems can be eliminated. Additionally, performance, life

expectancy and efciency of both the motor and the drive itself are signicantly enhanced.

ELIMINATE NUISANCE TRIPPING

Transients due to switching on the utility line and harmonics from the drive system can cause intermittent

tripping of circuit breakers. Furthermore, modern switchgear, equipped with solid state trip sensing devices is

designed to react to peak current rather than RMS current. As switching transients can peak over 1000 volts, the

resulting overvoltage will cause undesirable interruptions. A reactor added to your circuit restricts the surge

current by utilizing its inductive characteristics, and therefore eliminates nuisance tripping.

SECTION 3

EXTEND THE LIFE OF SWITCHING COMPONENTS

Due to the attenuation of line disturbances, the life of your solid state devices are extended when protected

by the use of a HPS line reactor.

SATURATION

Due to the care in the selection of the core material with its optimum ux density, HPS line reactors will not

saturate under the most adverse line conditions. Since the inductance is linear over a broader current range,

equipment is protected even in extreme overcurrent circumstances.

EXTEND THE LIFE OF YOUR MOTOR

Line reactors, when selected for the output of your drive, will enhance the waveform and virtually eliminate

failures due to output circuit faults. Subsequently, motor operating temperatures are reduced by 10 to 20 degrees

and motor noise is reduced due to the removal of some of the high frequency harmonic currents.

Normal sine wave from the utility supply.

LOW HEAT DISSIPATION

Particular attention has been focused on the design and eld testing of this product line. The result is

reactors with ideal operating features including low temperature rises and reduced losses. HPS reactors will

operate efciently and heat dissipation in your equipment will be of minimal concern.

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© Hammond Power Solutions Inc.

Data subject to change without notice.

SECTION 3 LINE REACTORS

MINIMIZE HARMONIC DISTORTION

Non-linear current waveforms contain harmonic distortion. By using a HPS line reactor you can limit the

inrush current to the rectier in your drive. The peak current is reduced, the waveform is rounded and harmonic

distortion is minimized. Current distortion typically is reduced to 30%.

Severe harmonic current distortion can also cause the system voltage to distort. Often, high peak harmonic

current drawn by the drive, causes “at-topping” of the voltage waveform. Adding a reactor controls the current

component, and voltage harmonic distortion is therefore reduced.

The total harmonic distortion of variable speed drives produces complex
wave shapes such as the phase current shown above. The challenge for
today’s designers is to effectively minimize these line problems.

SECTION 3

SHORT CIRCUIT CAPABILITY

HPS line reactors can withstand current under short circuit conditions, reducing the potential of severe

damage to electronic equipment. In a short circuit, the inductance of the coil is necessary to limit overcurrent

after the core has saturated. HPS has extensive experience in designing and testing dry-type transformers to

withstand short circuits for the most demanding applications, and this experience has been applied to line reactor

design.

REDUCE LINE NOTCHING

Whenever AC power is converted to DC by a rectier using a non-linear device, such as an SCR, the

process of commutation occurs. The result is a notch in the voltage waveform. The number of notches is a

function of both the number of pulses and the number of SCR’s in the rectier.

Line reactors are used to provide the inductive reactance needed to reduce notching, which can adversely

effect equipment operation.

A voltage waveform illustrating line notching. Line
reactors are used to provide the inductive reactance
needed to reduce such notches.

© Hammond Power Solutions Inc.

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Data subject to change without notice.