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Isolation Transformer - Line Conditioner

Three Phase Ultra Isolation Transformers - Line Conditioner

We are Manufacturer, Supplier, Exporter of Three Phase Ultra Isolation Transformer Line Conditioner from Ichalkaranji. Our set up is situated in Ichalkaranji, Kolhapur, Maharashtra, India.

VEPL – Ultra Fast Series Isolation Line Conditioners / Ultra Isolation Transformer A double wound transformer with multiple shielding for Capacitive or Faradic Isolation (reduction of capacitive coupling) Creates Galvanic Separation between Primary & Secondary Supplies. This transformer has very high attenuation of common mode transients thus preventing passage of voltage transients, spikes and galvanic leakage in the common mode from reaching sensitive electronic equipment like computers, medical equipment and CNC machines. It also addresses problems related to poor input neutral. The Ultra Isolation transformer can be designed to provide output voltages to suit machine requirement.

Isolation transformer, as its name indicates it isolates. Yes, it isolates powered device from power source, just for safety purpose we isolate them. In case is there any problem with the power source our device should be safe, It should not be damaged. The isolation transformer is basically a transformer with similar windings at both primary and secondary side. Isolation transformers provide galvanic isolation and are used to protect against electric shock, to suppress electrical noise in sensitive devices. This also used to block the interference due to ground loops. An isolation transformer is a transformer, often with symmetrical windings, which is used to decouple two circuits. An isolation transformer allows an AC signal or power to be taken from one device and fed into another without electrically connecting the two circuits. Isolation transformers block transmission of DC signals from one circuit to the other, but allow AC signals to pass. They also block interference caused by ground loops. Isolation transformers with electrostatic shields are used for power supplies for sensitive equipment such as computers or laboratory instruments. In electronics testing, troubleshooting and servicing, an isolation transformer is a 1:1 power transformer which is used as a safety precaution. Since the neutral wire of an outlet is directly connected to ground, grounded objects near the device under test (desk, lamp, concrete floor, oscilloscope ground lead, etc.) may be at a hazardous potential difference with respect to that device. By using an isolation transformer, the bonding is eliminated, and the shock hazard is entirely contained within the device. Isolation transformers are commonly designed with careful attention to capacitive coupling between the two windings. This is necessary because excessive capacitance could also couple AC current from the primary to the secondary. A grounded shield is commonly interposed between the primary and the secondary. Any remaining capacitive coupling between the secondary and ground simply causes the secondary to become balanced about the ground potential.

The transformer which has two kinds of windings be it be single phase transformer or three phase transformers. Every transformer does have input winding, which is called primary winding, and the output winding which is called secondary winding. Input voltage is fed to primary winding and the output of the transformer is connected to the load. The transformers generally used to isolate the input and the output supply. There is only magnetic coupling between primary winding and secondary winding. This transformer is called isolation transformers. These transformers are available in single phase and three phase. In single phase there will be three connections i.e., input line, input neutral and input earth. In three phase transformer there will be five wires connected to input of the transformer. Three connections are live connections, forth connection is neutral, and the fifth connection is earth or ground connection.

The purposes of isolation transformer are to isolate input power connections with output power connections of the transformer. Whatever the power quality problems exist on input side of transformer are magnetically transferred to output side of the transformer. It is observed that the leakage current between input and output can be reduced to the great extent by incorporating multiple shielding’s at primary and at secondary windings and at the transformer core. Most of the leakage currents can be reduced by incorporating multi stage and multiple shielding, these shielding are incorporated as per the design technique, while constructing the design of the transformer. There are many power quality problems exists on incoming power lines due to which there are lot of failures and premature failures and malfunctioning of the equipment’s are happening, and this equipment’s failures are causing a considerable waste of production, down time and money. Many such failures are occurring in electronic products because of not incorporating multi shield transformers which are fitted in the equipment’s. Most of the transformers used in electronic equipment’s do not exhibit low leakage and low capacitance. Since the electronic equipment’s are not fitted with multi shielded transformers the equipment’s are causing heavy losses to the user, and not incorporating multi shield transformer is one of the major causes of failure of equipment. The non-shield transformer will be having high leakage current and high coupling capacitance due to which many equipment’s are overheating and causing power losses and sometimes fire hazards. Most of the solid-state device’s semiconductor products and micro controller-based products do require quality power to operate smoothly. Many electrical and electronic products are being made “Smart” by using various micro controllers. The clean power is a life blood for trouble free functioning. Generally, there are many power quality issues being encountered continuously

Voltage fluctuations, Power failures, black out, brown out, under voltage, over voltage, sags, dips, surges, swells, impulses, spikes, notches, transients, EMI effects, RFI effects, TVI effects, EMP effects, harmonics effects, differential mode, events, common mode events etc. are some of the reasons which is causing heavy stress on all semiconductor equipment’s. Apart from voltage fluctuations which are visible there are many invisible power quality problems which is present on power lines. They are sags, are cycle to cycle decrease in power line voltages on any of the phase power lines in the three-phase power system. There are voltages dips are very short time occurrences. Some dips are visible some are not visible which can be solved by using the best quality isolation multi shield transformers. Surges are cycle to cycle increase in power line RMS voltage on any of the three phase lines on very short time. Spikes are over voltage an impulse which is ranging from 1000 volts to 10000 volts for very short time super imposition on AC power sine waves. Notches are very short time impulse voltages which are similar to spikes but it is reverse polarity to the instantaneous value of the AC sine wave. Notches are typically too fast to observe. These typically last long as spikes but can be upon several milli seconds in the duration. Spikes and notches are usually appearing on power lines as a pair and oscillate on lines. For every notch there will be immediately following spikes due to line inductance and capacitance.

Transients are very short-term event which occurs on power lines, all power line disturbances are transient by definition. EMI broad spectrum electromagnetic noise interference either conducted on AC Power lines directly or radiated to the power lines than conducted to the susceptible equipment. RFI is electromagnetic noise interference in the radio spectrum. TVI is electromagnetic interference in the television spectrum. EMP is a very large and very fast rising electromagnetic pulse caused by catastrophic events. such as lightning strikes and nuclear detonation.

Harmonics are sinusoidal currents and voltages with frequencies that are integral multiples of the fundamental power line frequency the Harmonics distort the normal the normal sine wave. There are normal and differential mode seven harmonics which occur across the normal current carrying of the power lines hot wires to neutral wires. Also called as transverse is metallic mode. Common mode events occur from current carry wires and hot and neutral wires. Relative to the safety ground wire.

To provide multi-level protection to all costly equipment’s we have designed a power protection equipment with ultra-high isolation transformer with RFI/ EMI filters, surge suppressors, gas discharge tubes and MOV’s as per the site conditions.

Most of electrical related problems can be encountered with the multiple shielding transformers with box type shielding. Each transformer is fitted with appropriate capacity line filters RFI/EMI filters surge protection equipment’s there by most of line bound power quality issues can be tackled with this multi shield transformers.

Our technology designed innovative shielding technology transformers are manufactured the following manufacturing method.

The transformer is designed at 150% of its rated load. The core is designed with low losses transformer core. The primary winding has been slitted in to two coils for each phase. There is a gap has been incorporated in primary windings. The primary winding is provided with three shielding’s. The secondary winding has been spilt in to two parts for each phase there is a gap provided between two parts of secondary winding and total secondary winding has been provided with three shields. One common shielding is provided for entire transformer covering core of the transformer. Thus, transformer is having seven shielding. By incorporating with the multiple shielding the coupling capacitance of the transformer is greatly reduced and magnetic leakage is greatly reduced through core and coils. This design and construction of the transformer which provides very high protection against many types of power quality electrical problems. We claim patenting about the design of transformer, the construction of transformer, the shielding construction of the transformer.

Primary to Secondary Coupling Capacitance.

Coupling capacitance occurs in transformers due to the physical proximity of and electro static coupling between the primary to the core, primary and to the secondary windings, from the secondary windings to the core and between turn to turn in all coils. The capacitance is distributed between the different layers within the windings between primary and secondary windings. The coupling capacitance or capacitor in the transformer only allows AC signals between the capacitors and blocks the AC signals. Spikes, surges, noises, harmonics notches, transients, RFI/EMI noises are in the nature of high frequency compare to fundamental frequency.

For good power quality these spikes, surges, noises, harmonics, notches, transients, RFI/EMI to be blocked at input side of transformer which is possible only when the transformer coupling capacitance is extremely low. Hence the new method of reducing coupling capacitance has been introduced and implemented.

Leakage current and its effects on the performance of capacitance of the transformer. The leakage current flows from coupling capacitance. If coupling capacitance is high there will be more current flows due to which power quality is detorated. Once the coupling capacitance is less the performance of power quality maintenance increases due to multi shield transformer. Hence multi shield transformer technology is developed to reduce the coupling capacitance and to reduce leakage current. The transformers which are used for medical purpose and power quality improvisation purpose the transformers must exhibit very low leakage current and very low coupling capacitance. Due to introduction of multi shield low capacitance low leakage transformers will increase power quality and saves substantial power and reduce failures of electronic circuits and gadgets and associated machineries.


  • Better Heat Transfer
  • Lower Temperature Rise
  • Lower Weight
  • Better Surge with Standing Capacity
  • Better Suited for Harmonics
  • No Hot-spots
  • More Efficient
  • Low inter-winding capacitance
  • Good DC galvanic isolation
  • High attenuation -100 dB in common mode up to 10 kHz
  • Optimum transformer design ensures good load regulation

Technical Specifications:

  • Connection Details DELTA: STAR / STAR: DELTA Vice Versa.
  • Input Voltages 200V/380V/415V/480V/575V 3 Phase 3 Wire / 4 Wire.
  • Output Voltages 200V/380V/415V/480V/575V 3 Phase 3 Wire / 4 Wire.
  • Ratio 1:1 / 2:1
  • Operating Temperature 55 Deg Celsius.
  • Cooling Natural, Forced Fan Air Cooled, Oil Cooled as per requirement
  • Regulation Better than 3.0%
  • Power Factor 0.8 lagging
  • Insulation 2.5kV for 1Min
  • Megger Value Greater than 1000 Mega Ohm.
  • Leakage Current > than 15uA
  • Common Mode Attenuation 80dB to 100dB
  • Line Transients Acts as Series Filter Eleminates Line Voltage Transients
  • Also Eliminates Neutral / Star related problems.
  • EMI / RFI Interference Serves as Passive Filter reduces effects of mains line problems.
  • Designed to Meet UL 60950-I standards, Protection class IP 20.
  • As per is 2026 part I & II (IS 1171)


  • CNC Machines
  • Bio Medical Equipment’s
  • Printing Machineries
  • Mobile Towers / Transmitters.
  • Scientific Equipment’s
  • Textile Machineries.
  • Oil & Gas Plants
  • Large Computer Installations
  • Garment Equipment’s and many more.

Ultra - Isolation Line Conditioner
Oil Cooled Ultra Isolation Transformer
Dry Type K Rated Ultra Isolation Transformer
  Static Voltage stabilizers Servo voltage Stabilizers Tap changing Voltage Stabilizers
Technology IGBT converterbased DSP controlled Electromechanicalvariac based Auto transformerwith SCR based tap control
Correction speed 2000V/sec Typical 35V/sec Slow
Correction time Less than 10 msec 1000 ms - 5Sec 200 ms-1Sec
Auto bypass Yes No No
Voltage Stability 1% 10% 2%
Cycle by cycle Voltage regulation Yes No No
System protections - Short circuit
- Over current
- Over/under voltage
None None
Overload capability 125% for 10 min
150% for 1 min
No No
Load protection capabilities Excellent None None
Interrupts power path at the time of regulation No No Yes
Power cycling transients No Yes Yes
Dynamic load handling capability Yes - suitable for all kind of loads No No
Regenerative load handling capability Yes No No
Soft start features Yes No No
Individual phase compensation Yes No No
Communications for remote monitoring or SCADA compatibility RS 485, Modbus, TCP/IP and others on request none none
Reliability Excellent Good Fair
Size Very Compact Bulky as its oil cooled Compact
Maintenance No Yes Yes (In case of Relay)