Electric machine, regardless of its size, be it a small power tool or a gigantic set of manufacturing
equipment, will operate properly only on electrical
power with a voltage level that is within its allowable tolerance.
When the supply voltage fluctuates beyond a
machine’s tolerable limit, it results in over-voltage rounder-voltage stress, which can have detrimental effect on the machine.

Usually, over-voltage and under-voltage electrical
problems are beyond the control of any electricity
user. One of the possible means to tackle such
problems is by the use of automatic voltage stabilizer that can provide stable output voltage from fluctuating

Functional Block Diagram of Micro-Processor Controlled Multi 
Cascading Transformer (MCT) Stabilizer

How it works:
Three or more double-winding transformers arearranged in a cascade manner with their secondarywindings connected in series with the power linebetween the input and output circuit. The primarywindings of the transformers are connected to the mains supply via power switching devices that are commanded by a microprocessor.

Each transformer can be commanded to feed a specific amount of subtracting or adding voltage into the power line via its secondary winding to decrease or increase the output voltage respectively. All switching operations are carried out on the primary side of the transformer without interrupting the secondary winding that constitutes part of the power line circuit.

A microprocessor based closed–loop feedback control circuit is used to monitor and maintain the output voltage tolerance. A portion of the output voltage is fed-back to the microprocessor and compared with a preset reference that corresponds to the preset output voltage level to determine the amount of drift from the preset level. The microprocessor calculates the compensating voltage and activates the number of transformers to be switched into the circuit to restore the output to its rated voltage level.

All switching sequences are synchronized to the zero-crossings of the current waveform to eliminate switching transients. The switching operation can be configured to achieve very fast correction time to cater for specific application requirement.

Power line conditioners are stabilizers incorporated with voltage isolation or filter networks to suppress transient electrical disturbances such as voltage spikes and radio frequency interference (RFI).

Isolation transformer, power line filters or surge suppressors may be incorporated depending on load applications.


No Sliding Electrical Contacts
In motor-driven-variac technology, sliding contacts are the major contributor to the inherent wear and tear problem associated with the design. MCT stabilizer employs digital switching technology, eliminating the use of sliding contact, thereby achieving long term reliability.

High Efficiency
Motor-driven-variac technology uses two sets of power transformers: a variac and a boost-buck transformer, which contribute to almost all of the energy loss in the stabilizer. The multiple transformers used in MCT stabilizer have a loss of energy equal to that of the buck-buck transformer minus that of the variac. As a result, the power efficiency is almost improved by two fold.

Fast Correction Time
Depending on the application requirement, MCT stabilizer can be configured to attain its rated output voltage level in not more than 0.1 of a second responding to a full range of supply voltage variation.

Automatic Bypass Device
In the unlikely event of component failure that may result in the loss of output voltage regulation, MCT stabilizer is incorporated with automatic bypass device to switch the load directly to the supply, bypassing the stabilizer circuit, without interrupting the output power. Modular Design For Easy Maintenance The absence of complicated mechanical attachments and modular design offers ease of access to all internal components, considerably cut down time and cost of maintenance work.

Individual Phase Control
MCT three phase stabilizer is made up of three independent single phase stabilizers integrated into a single enclosure allowing 100% unbalance load or
three individual single phase load.

Intelligent Soft Start
When MST stabilizer is powered up, the output voltage is made to follow the input to avoid undervoltage or over-voltage problem. The voltage correction function is initiated to regulate the output voltage only in 5 seconds after the supply power is connected to the stabilizer.

Single Phase : 240V ±10%*
Three Phase : 415V ±10%*
Frequency : 50Hz / 60Hz ±5%
Power Factor : 0.98
Single Phase : 240V ±2%*
Three Phase : 415V ±2%*
Frequency : 50Hz / 60Hz ±5%
Harmonic Distortion : Nil
Efficiency : Better than 98%
Load Power Factor : 0.5 lagging / leading
* Difference range of input and output voltages is available on request.
Operating Temperature : 0 to 45 ºC
Relative Humidity : 0 to 90% non-condensing
Audible Noise at : <35dB
1 meter
• Power On Indicator
• Output Voltmeter (3KVA and above)
• Output Ammeter (10KVA and above)
• Input Breaker (90 KVA and below)
  • Availability: In Stock