FAQs regarding voltage stabilizer and regulators.

A voltage stabilizer is a device that delivers stable voltages. Every regulator is designed for a specific voltage band. As long as the input voltage is within that band, it will correct it and ensures constant voltage at its output. Thus, it offers protection to the devices connected to it from voltage fluctuation. It also enhances equipment lifespan.

Power coming from the utility grid is not always pure, stable, and safe. It has Sag, Swell, overvoltage, overcurrent, spikes, and surges. All these compromises power quality. Every machine demands a pure power supply. Thus, a voltage stabilizer helps to supply fluctuation-free voltages. It stops all power impurities and protects your load.

Based on the working principle, there are three types of voltage stabilizers. Servo, relay, and static systems are three types. Everyone has its advantages and disadvantages.

It is a voltages stabilizer working on the servo motor controlled mechanism. A servo voltage stabilizer consists of an autotransformer or dimmer, buck-boost transformer. Also, it has a servo motor with an electronic circuit. The primary side of the buck-boost transformer is fed by a dimmer.

A rotating arm with a carbon brush is connected to the servo motor, and it can change the number of turns of the dimmer. So, when low or high voltages are at the input, the electronic circuit gives a single to the servo motor. Servo motor moves the arm to increase or decrease the turn of the dimmer, and hence primary voltage of the buck-boost transformer changes. As a result, the buck-boost transformer can adjust the output voltage to keep it stable.

Unlike a servo motor-controlled unit, a static voltage regulator has a complete electronic design without moving parts. It has a power module, buck-boost transformer, and DSP controller. The power module is generally made up of IGBTs. Hence, it is also known as an IGBT stabilizer. Voltage correction occurs by adding or subtracting the privacy voltage of the buck-boost transformer connected to the power module’s output. And Power module can generate voltage with the help of the PWM method governed by the DSP processor.

There are the following differences are as follow:

1. Servo regulator has moving parts while static regulators have pure electronic design without any movie part. Hence, the static unit has low maintenance and long life than the servo unit.
2. The static stabilizer has the flexibility to customize easily. We can incorporate EMI/RMI filter or automatic bypass without any additional cost.
3. The static voltage regulator has a faster voltage correction speed & more output voltage stability than the motor-controlled unit. 
4. The electronic units are lightweight & compact than the equivalent capacity of the servo regulator.
5. We can implement short circuit protection in the static system without adding additional hardware. 

It depends on the type of load you have. Thus there can be the following possibilities:

1. If you only three-phase load, then select 3 phase regulator.
2. If you only single-phase load, then you can choose a single-phase or three-phase unit. Make sure that 3 phase unit has independent phase control to avoid phase unbalancing.
3. If you mix single & three-phase loads, then you should choose a 3-phase stabilizer only. Single ph load needs to distribute on all phases equally. 

It is regular static or servo voltage regulator that is housed in a weatherproof covering. This weatherproof covering protects the unit from water, dust, and heat. In short, it can fight harsh weather conditions without compromising performance. These outdoor cabinets are designed as per IP54 or IP55 protection standards.

In some applications, need to install equipment in the open space. For example, consider a case of telecom tower, traffic lights, airports, or advertisement holdings. All these applications need a stable power supply. But, there is no covered space to install the regulator. The unit needs to protect itself from weather and vandalism. Thus, we need an outdoor voltage stabilizer with robust weatherproof IP55 or IP55 casing in such cases.

It is nothing but a static voltage stabilizer that uses IGBTs in its power module. There are many advantages of using IGBTs over SCRs. For example, it offers low input THDi, high rating, and more reliability.

It is because of its electromechanical design. Even with a built-in AVR, a generator’s output constantly fluctuates. The voltage variation can damage the computer, ACs, and other home appliances. Thus, whenever using a Disele generator to supply temporary power, it is always an excellent practice to connect a voltage stabilizer at its output. The rating of the voltage regulator should be at least 30% more than the generator’s capacity. Also, the number of phases should match.

An isolation transformer creates galvanic isolation, avoids ground loop, and reduces voltage between ground and neutral. It physically isolates the input from the output and hence avoids shocks to the use.

1. A ground isolation transformer can create new light neutral. Hence, it can reduce neutral to ground voltage to zero, which many Electronic loads need.
2. It can reduce the noise level in electronic and electrical circuits. Thus, it is often used with telecom and broadcasting equipment.
3. A medical transformer is connected at the input of medical devices to offer the operator and patient safety. 
4. It can correct and reduce the harmonics.
5. A Marine isolation transformer can protect the load from surges.

A constant voltage transformer consists of a high voltage resonant winging and a capacitor to correct the fluctuating voltage. It has to compensate & neutralize winding with a capacitor connected between compensating and secondary winding. Thus, it is also called a Ferroressonant transformer.

A frequency converter or a frequency changer is a device that can convert input frequency to desired output frequency value. It is required to run 60Hz appliances in a country with a 50hz power grid. 50Hz to 60Hz converter often used to run in UAE that imported from the USA. Also, it uses for motor & pump control and energy saving.

Worldwide, counties use eight 50 or 60Hz power grids. Due to this, we need 50Hz to 60Hz converters to run a machine that needs input power with 60Hz frequency in many countries. For example, devices import from the USA is designed for 60Hz frequency. We need this Hertz converter if we want to run these devices in Qatar, Kuwait, Oman, or UAE.

Both types of frequency changers have their pros and cons. For higher kVA motor loads, a rotary-type system is more economical. But, for smaller ratings, a static frequency converter is more practical. The rotary unit achieves conversion by coupling the motor to the generator shaft. In other words, it is designed for a specific output frequency that can not change. However, we can convert the same unit from 50Hz to 60Hz to 60Hz to 50Hz or 400Hz system in static design.

To calculate the required capacity of the voltage regulator, we need to add up the KVA, KW, or Amp rating of all loads that you want to connect to that regulator. For single-phase load, we can calculate KVA capacity can by multiplying voltage to the current requirement of that load. Similarly, we can get a KVA rating for three-phase loads by multiplying line voltage to line current and multiplying the result by three. Once you calculate KVA for each device at your facility, add them to get the total required rating of the voltage stabilizer.

The primary difference is the mode of cooling. As the name suggests, an air-cooled stabilizer uses forced air to cool its components. On the other hand, the oil-cooled regulator used oil as a cooling medium. An oil-type voltage stabilizer needs regular maintenance to change its oil. However, an air-cooled system does not require any similar maintenance. An oil-type unit and robust but heavy and not environmentally friendly.

Voltage stabilizers have been used in all sectors, right from home to heavy industries. Most commonly, it is used in the following sectors:

• At broadcasting and telecom stations.
• For cold storage room equipment.
• It is used along with the Disele generator used for a temporary power supply.
• It helps to protect CNC machines from voltage fluctuations.
• Lift and elevators need a servo voltage stabilizer.
• Textile, Packaging, Hospitals industries need servo regulators.
• Datacenter, server rooms, and other electronic equipment bases machines need static voltage regulators.

Variac is nothing but an autotransformer with tapping at outputs to generate different voltages. It is used for boosting line voltages and simulate overvoltage or Undervoltage conditions for testing of equipment. Manual and motorized are the two types of variac available with three or single-phase configurations.