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05-10-2026

Three-phase electrical systems are widely used for operating equipment such as lifts, UPS systems, air conditioners, motors, pumps and different types of machinery. In such applications, maintaining the correct sequence of all three phases is important for proper electrical operation. At Selfguard Automation and Controls, we provide our Automatic Phase Sequence Corrector (PSC) to keep all three phases in the correct RYB sequence, irrespective of the sequence coming from the input supply.

 

Understanding Phase Reversal

In a three-phase system, the phases are required to remain in the correct sequence. The Selfguard Automatic Phase Sequence Corrector is specifically designed to ensure that the output maintains the correct RYB phase sequence even when a different sequence is received from the incoming supply.

This makes phase sequence management especially relevant for three-phase installations where equipment depends on a properly arranged three-phase mains supply.

 

What Can Cause an Incorrect Phase Sequence?

The incoming three-phase supply may not always be available in the required RYB sequence. Instead of depending on the incoming sequence, our Automatic Phase Sequence Corrector automatically keeps all three phases in the correct sequence. The unit therefore helps manage situations where the phase order available from the input supply is different from the required sequence.

The Selfguard PSC is designed specifically for installation with a Three Phase Mains Supply.

 

Where Correct Phase Sequence Is Important

Our Automatic Phase Sequence Corrector can be used with a variety of three-phase electrical equipment. According to its designed applications, the unit is suitable for:

  • Three-phase lifts
  • UPS systems
  • Air conditioners
  • Motors
  • Pumps
  • Machinery

By maintaining the correct RYB sequence, the unit provides a practical solution for installations where three-phase equipment is connected to the mains supply.

 

Additional Protection for Three-Phase Systems

Phase sequence correction is not the only function provided by our unit. The Selfguard Automatic Phase Sequence Corrector also provides protection against imbalanced voltage. In addition, the unit is equipped with an inbuilt Single Phase Preventer.

These features make the PSC suitable for three-phase installations that require phase sequence correction along with protection against imbalanced voltage and single-phase conditions.

 

Preventing Phase Sequence Problems with Selfguard PSC

The most direct way our product helps prevent phase sequence problems is by ensuring that all three phases remain in the correct RYB sequence, regardless of the sequence received from the input supply. Our Automatic Phase Sequence Corrector is available in different capacities depending on the electrical requirement. The available ratings include:

15 KVA, 25 KVA, 40 KVA, 62.5 KVA and 82.5 KVA.

This range allows the product to be considered for different three-phase applications and installation requirements.

 

Selfguard Automation and Controls

Selfguard Automation and Controls was established in 1990 and is engaged in manufacturing electrical and electronic products related to mains, generator and agricultural automation. We use the latest microcontroller technology and aim to manufacture quality products according to customer requirements.

With our Automatic Phase Sequence Corrector, we provide a solution designed to maintain the correct RYB sequence in three-phase mains systems while also offering protection against imbalanced voltage and an inbuilt Single Phase Preventer. For three-phase lifts, UPS systems, air conditioners, motors, pumps and machinery, the Selfguard Automatic Phase Sequence Corrector provides a dependable way to maintain the required phase sequence from the incoming mains supply.