Series

STATIC Power Factor Correction Equipment

400 Vac  50 Hz    Capacitors MFHC  460 Vac  3 In

Static P.F.C. equipment differs from the standard equipment for the following reasons:

·    The reactive power regulator has a switching time of the banks extremely quicker than the standard regulator

·    The device for switching the capacitors banks is electronic, controlled by thyristors, with the capability of switching the capacitors at zero crossing.

Static switching by thyristors has the following advantages:

Static P.F.C. equipment differs from the standard equipment for the following reasons:

·    The reactive power regulator has a switching time of the banks extremely quicker than the standard regulator

·    The device for switching the capacitors banks is electronic, controlled by thyristors, with the capability of switching the capacitors at zero crossing.

Static switching by thyristors has the following advantages:

Industrial plants where the load varies greatly throughout normal operation will require automatic P.F. equipment in order to connect the necessary capacitive power.

WHY SHOULD POWER FACTOR BE IMPROVED?

THE BENEFITS ARE THE FOLLOWING:

REDUCED UTILITY CHARGES

INCREASED SYSTEM CAPACITY

The thermal capacity of generators, transformers and cables limit the kVA that can be supplied by the system. Reducing the KVAR demand from existing load by installing capacitors, allows additional load to be added to the system.

IMPROVED VOLTAGE

High demand of reactive power increases the voltage drops across transformers, cables and other system components. The result is a decreased utilization voltage.

The voltage drops can be limited by increasing the power factor.

REDUCED CIRCUIT LOSSES

Rated voltage of P.F.C. Equipment is the voltage for which the equipment has been designed.

To ensure that premature failure of the equipment is eliminated, the operating voltage should not be greater than the rated voltage.

Voltage factor x Un

Working temperature  is a fundamental parameter for the safe functioning of P.F.C. Equipment. Consequently, it is very important to have  sufficient heat dissipation inside the P.F.C. Equipment cubicle. Ventilation should be adequate to prevent the temperature rise exceeding the limits of the capacitor design.

Standard Power Factor Correction Equipment are not suitable to be used in places where the following special conditions occur:

The ever-increasing use of static converters, rectifiers and other generators of harmonic current and voltage distortion on the supply network make it essential to carefully evaluate the installation of P.F.C. equipment in order not to create a resonance condition, which amplifies overcurrent and overvoltage, becoming dangerous for the capacitors and other connected loads.

The choice of the right P.F.C. equipment is related to the power of the non-linear loads and the power rating of the transformer.

THDI max. %

THDI alarm %

THDI%-OFF

THDI MAX

In recent years, P.F. correction has evolved greatly due to the presence of harmonic generated loads.

These loads produce harmonic currents and voltage which distorts the network waveforms.

The main source harmonic generated loads are AC/DC static converters used for drive and UPS systems.

For these reasons it is essential that any installation of P.F.C. equipment must be carefully evaluated, the possible presence of harmonic currents in the network could create conditions of parallel resonance between the reactor of the network and that of the capacitors, generating overcurrents and overvoltages, which would cause premature failure of the power factor correction capacitors.

Rated Voltage

400 Vac – Max Overvoltage 1.1 Un

                 Max Overcurrent 2.0 In

Rated Frequency

50 Hz (60 Hz on request)

Rated Power

Referred to rated frequency and voltage

Voltage of Auxiliary Circuits

110 Vac feeded by a single-phase transformer

Working Temperature Range

-5°C/+50°C

Cubicle

20/10 mm sheet steel, protected against corrosion by a phosphating treatment. Epoxy powder painted, RAL 7032 colour (other colours on request)

External Protection Degree: IP30 (IP40-IP54 on request)

Locking system: by key

Ventilation

Forced

Isolating Switch

Three-pole with door interlocking device

Supply

Cable entry from the bottom

Wiring

By N07VK CEI 20-22 flame retardant cables.

Aux. circuits are identified as in the electrical drawing

Fuses

Each bank of capacitors is protected by a set of three fuses (NH00 type) with high breaking capacity. Also the auxiliary circuits are protected by fuses.

Activation

Thyristors zero-crossing static devices.

Capacitors

Self-healing bimetallized paper and polypropylene single-phase capacitors, equipped with overpressure safety device and discharge resistor. Biodegradable non toxic filling, PCB free. Delta connection.

MFHC 460 Vac 3 In Series.

IMQ approved.

Capacitance tolerance: -5% +10%

Dielectric losses: <0.3W/kvar

Temperature class: -25/D (55°C)

Regulator

Varmetric measurement by means of a C.T. (secondary 5A) – not supplied

Reference Standards

Comply with L.V. 73/23 (93/68) EEC Directive

Capacitors: CEI EN 60831-1/2

Equipment: CEI EN 60439-1

Options (on request)

·   Protection and Control Instrument SPC2

Protection Degree: IP40 - IP54

G type: cable entry from the top

Power

at

400 Vac

Power

of banks

Isolating

switch

Rated

Power

at

415 Vac

W x D x H

A

500x

500x

600x

625x

600x

625x

1815

600x

625x

1200x

625x

1200x

625x

1200x

625x

2065