Transformers
The transformer is the backbone of a power system. Among the conveniences that transformers offer is easy voltage regulation, and that is why in AC systems they are the preferred choice. A transformer is a static device that changes alternating current electrical energy from one circuit to another at the same frequency, the only thing that changes is the voltage level.
The windings of the transformer carry information about whether it is step-up or step-down. If the number of turns of the secondary side is greater than the number of turns of the primary side, then the transformer is a step-up transformer. In case the number of windings of the secondary is less, the transformer should be step-down.
Sentera’s autotransformers are step-down transformers.
Transformers are widely used in AC systems for the following reasons:
- Electrical energy can be generated at the most economical levels possible.
- Transmission voltage is stepped down at many stages for distribution and use for residential, commercial and industrial users.
An autotransformer and an isolation transformer are distinct in their design and functionality. An autotransformer employs a single winding (coil) that serves both as the primary and secondary winding. Different voltage taps are utilized to achieve varying output voltages while the isolation transformer has two separate windings, the primary and secondary, providing electrical isolation between the input and output.
Autotransformer allows for voltage adjustment through its various taps, offering a range of reduced voltages. When it comes to electrical isolation, it provides limited electrical isolation between the input and output, as the windings are not entirely separate.
The operation of a transformer is based on two basic principles:
1. The time-varying electric current in the primary coil creates a time-varying electromagnetic field.
2. The electromagnetic field creates by electromagnetic induction an alternating electric current via electromagnetic induction.
Sentera's autotransformers are characterized by a single coil configuration. Through the utilization of distinct voltage taps, these transformers offer varying reduced voltages. The singular winding of an autotransformer serves the dual purpose of acting as both the primary and secondary winding concurrently. This design yields a more compact and lightweight construction when juxtaposed with conventional dual-winding transformers.
This type of transformer is characterized by compact dimensions, high reliability and long service life. It is very often used for laboratory or experimental purposes in a number of industries and production processes, as well as for ordinary household purposes when certain physical quantities need to be regulated. The principle of operation of autotransformers is based on the fact that there is no galvanic separation of the primary winding from the secondary, just the opposite. The coils are connected directly, resulting in not only electromagnetic but also electrical connectivity. These qualities contribute greatly to the high efficiency, as only a part of the power is converted.
Typical application field of autotransformers
The autotransformer is commonly used for voltage regulation, especially in applications where a variable output voltage is required. It is also integrated into devices like motor speed controllers and power supplies.
Sentera’s autotransformers are integrated into the transformer fan speed controllers manufactured by the company. Moreover, they stand as standalone components, adeptly meeting the voltage reduction requirements in diverse applications.
To be used as standalone device, Sentera’s autotransformers feature terminal block connections. The screw terminal blocks facilitate easy connection and adjustment of voltage taps, allowing for precise control over the output voltage and simplifying both the installation and servicing process. By changing the point of connection, the different voltage ratios are achieved. The primary and secondary voltages are interconnected, i.e. the secondary voltage is derived from the same winding as the primary voltage.
The design of Sentera’s autotransformers is particularly suited for mounting in electric cabinets and switchboard mounting to be an integral part of control and distribution systems. Besides a mounting bracket, they have special impregnation, because even though the operated motor runs very silently, the autotransformer may produce some noise. Sentera’s special coating reduces this to the minimum level.
Sentera maintains an exclusive production line dedicated to autotransformers, underscoring our commitment to ensuring the highest standards of quality.