ELSPEC Equalizer ST - The Ultimate Motor Start-Up Solution
The Equalizer-ST is a real-time, dynamic reactive power compensation system for medium and low voltage drop motor startups that utilizes a proven industrial technology to provide the ultimate motor protection control solution for the challenges related to large motor startups.
Exclusive Technology
Cost effective fast reactive power compensation. Improves the power quality of the electrical network. Designed to limit voltage drop motor startup to local standards. Transient free switching. Centralized motor startup solution.
The Electrical Challenge
A motor start demands very high reactive power for a relatively short period of time. This demand creates typical reactive currents of 6-7 times the nominal current of the motor; consequently a voltage drop is developed in the local network that is usually not designed to withstand these temporary high currents. This voltage drop can create problems for other loads in the network and, if excessive, can prevent the motor from starting.
The Ultimate Solution
A more cost effective solution than Variable Speed Drives or Variable Frequency Drives.
In cases that there is a need to reduce the starting torque as well, EQUALIZER-ST is not used a standalone solution, but rather is combined with a soft starter to provide for the complete requirements of the motor:
In areas with weak electrical networks, a soft starter may not reduce the voltage drop enough for the motor to start each time. In this case, a EQUALIZER-ST can be used as a considerably less expensive substitute than a Variable Speed Drive (VSD) or Variable Frequency Drive (VFD) if speed control is not necessary for a manufacturing process.
In cases that there are Power Quality problems during the motor start, EQUALIZER-ST can improve the power quality
PFC Technology
Capacitor Group Switching
Elspec's systems switch capacitor groups on and off using state-of-the-art electronic switches (full compensation in less than 2/3 of a cycle). The connection and disconnection of capacitors occur precisely at zero-current crossing. This smooth connection avoids transient effects typically created by electromechanically switched power factor correction (PFC) systems, extending the life expectancy of the EQUALIZER dramatically.
Fast and Accurate Measurements
The controller uses FFT (Fast Fourier Transform) analysis of all phases each cycle. Power information, system status and detailed logs of events are displayed on a large backlit graphic LCD screen, or via communication using the user-friendly PowerIQ software.
Ideal PFC Control
Using exclusive automatic control algorithms and rapid electronic switching, total acquisition time (complete compensation of reactive current) is achieved in 2/3 cycle typical (50Hz = 13.3 ms; 60Hz = 11.1 ms), irrespective of the number of steps required. The power factor is controlled very accurately through an advanced open and closed-loop control & measuring system that uses information from all three phases, as well as accounts for the effect of harmonics (1 through 63). Minimum, maximum and average power factor modes, as well as threshold levels, can be selected for perfect compliance with specific network requirements. The EQUALIZER includes a unique solution for line-to-line loads, in which it calculates a transformer’s internal currents and compensates accordingly. Third party measurements have proven the EQUALIZER to be the ultimate solution to offer precise compensation for voltage drop and flickering.
SCAN Mode
The EQUALIZER is equipped with a unique SCAN feature that protects capacitors from exploding and contributes to longer life expectancy by reducing over-current and minimizing capacitor heating. The electronic switching element (unlimited operations) connects one capacitor group simultaneously as another group is disconnected. This operation occurs every few seconds, engaging each capacitor group in turn, with total compensation unchanged. This results in mean current reduction due to lower duty cycle (engagement time to cycle time). Together with the unique reactor design, temperature rise of the reactors is substantially reduced and the potential for cabinet overheating is minimized.
Consistent Capacity
Conventional electromechanical capacitor banks suffer from an ongoing cumulative reduction in capacity due to the effect of transients during connection and disconnection. This can be especially detrimental in tuned and detuned electromechanically switched systems where changes in the ratio between the capacitors and reactors shift the resonant frequency. This scenario can cause resonance, which can cause extreme damage to equipment in the facility. The EQUALIZER prevents this scenario, resulting in longer system life, lower maintenance costs and more consistent harmonic filtration over time.