Everything You Need To Know About Servo Stabilizer And Its Testing

Voltage stability is essential in electrical systems to guarantee secure and dependable equipment functioning. An unstable voltage can harm sensitive electronic equipment, which can also interfere with business operations and delay or cost-prohibitive repairs.

Using a toroidal core transformer, the servo-controlled stabilizer is a popular remedy that regulates output voltage within a small range, often within 1% of the standard voltage. This exact control regulates input voltage variations while safeguarding equipment and maintaining peak performance. This blog discusses servo stabilizers, how they function, and how to test them. 

What is a Servo Voltage Stabilizer?

A servo stabilizer is a system that uses a buck/boost transformer booster to supply the best voltage under the control of a servo motor. It controls current to the proper output by utilizing elements like control cards, dimmers, comparators, transistors, and MOCS. Together, the key elements work to offer the best possible voltage supply in building maintenance.

A dimmer is a circular variable transformer with a particular turn ratio of copper wire and a silicon CRGO toroidal core. Its main job is to modify the voltage supplied to the buck-boost transformer. The Buck Boost Transformer handles the remaining 50% of the output voltage, with the dimmer handling the other 50%. The dimmer will raise the input voltage, for instance, from 160V to 190V, while the Buck Boost Transformer completes the remaining work.

In servo stabilizers, the carbon brush is a movable component installed in the shaft to make contact with dimmers. If input voltage change is frequent, it may be erased early and require frequent replacements. Therefore, premium carbon brushes should be used by servo stabilizer producers.

As the name implies, it delivers the signal to different servo stabilizer components, such as the motor, dimmer, etc., so they may function by that signal and help in voltage stabilization as needed.

The fundamental component of a servo stabilizer, as the name implies, is a servo motor. Depending on the input voltage, the motor turns the arm attached to the dimmer either clockwise or anticlockwise.

Buck Boost Transformers have an EI CRGO core and are rectangular in shape. For further protection, they are submerged in a varnish tank. Before servo stabilizers are ready for regress testing, transformer varnish encases the windings to prolong coil life and shield them from the elements. Any wire coil can utilize it as an insulator. There are also isolation transformers, which are not the same as buck-boost transformers.

The purpose of a contactor is to shut off any servo stabilizer’s output if it rises over a certain threshold.

In contrast to MCCB, which is often utilized for overload protection, the MCB is used to turn on and off the servo stabilizer and provides short-circuit protection.

Advantages of Servo Stabilizer 

In contrast to conventional stabilizers, which could have observable steps or interruptions, servo-controlled stabilizers provide stability and smooth voltage change. This is especially advantageous for delicate weights or machinery.

Because of their adaptability and flexibility, these stabilizers can handle various voltage changes, guaranteeing efficient output voltage control and stabilization to satisfy particular application needs. Servo stabilizer testing services for commercial locations are helpful since low voltage circumstances may be tolerated while nighttime high voltage requirements can be satisfied.

What is the use of a Servo stabilizer?

The benefit of a servo stabilizer over a conventional stabilizer based on relays is that it is a dependable energy device and a voltage fixing system. Servo has many advantages for us, including the following:

1. A voltage correction output with a high degree of precision of one.

2. A system with fewer switches stabilizes varying voltage levels.

3. A sizable functional area, including Servo Stabilizer Testing Services for corporate offices, residences, and schools.

4. Strong load capacity, supporting at least 5000 KVA.

5. Step-less correction is the foundation for voltage.

6. Perfect hospital stability is ideal for complex equipment, including X-ray machines, CAT scans, radiation, and diagnostic tools.

7. Budget-friendly oil- and air-cooled transformers.

Servo Stabilizer Testing Services

Executing routine testing and maintenance on servo stabilizers is crucial to guarantee their dependable performance. 

In-person testing is essential for confirming that these stabilizers are in good functioning order. The testing procedure frequently involves a variety of checks and measures. This procedure aids with locating any potential problems or shortfalls that could have an impact on the functioning of the stabilizer.

Another crucial step in the testing procedure is insulation testing. It is feasible to evaluate the insulation’s integrity using a 500 V megger to measure the insulation between the stabilizer’s terminals and body. The widespread consensus is that a minimum insulation value of 5 M, measured at an environment temperature below 45°C, is appropriate. This can be done with the help of Servo Stabilizer Testing Services for residential homes.

The last phase in the testing procedure is load testing. This entails putting the stabilizer under the real load of the apparatus for at least six hours while keeping an eye on the output voltage and temperature. The stability of the stabilizer may be evaluated by ensuring that the output voltage and temperature stay within predetermined ranges.

Servo Stabilizer Testing Services in Hyderabad 

The autotransformer and servo motor are frequent areas of failure in servo stabilizers, so it’s crucial to use reliable parts to reduce failure risks and guarantee lifetime. For satisfactory operation, choosing the right variac rating and service in Hyderabad is essential. For air-cooled systems, 10-15% variation is advised.

Experienced professionals can assist you in negative circumstances, such as low input voltage and excessive load current, frequently causing various malfunctions. Potential failure is further impacted by carbon brush wear and tear as well as decreased spring tension. Contact a good professional for routine inspection and maintenance to resolve problems and ensure maximum performance.


Servo-controlled stabilizers are dependable for voltage stabilization in a variety of applications because they provide exact voltage regulation, smooth operation, and adjustable voltage fluctuation. A secure and stable electrical environment is provided for equipment and systems by thorough testing and regular maintenance, which ensures their performance and lifetime.