Mains Protection


A family of mains protection modules that provide the necessary protection functions to meet the requirements of all applications where generators operate in parallel with the mains.

Maintaining power supply stability

As the installed capacity in decentralized sources of energy continues to increase, the distribution system can become less stable resulting in a fluctuation of grid parameters such as voltage and frequency. To keep the equilibrium and ensure safe operation of the grid, mains protection is essential for every power source operating in parallel to grid.

As a result, Utilities and Distribution Network Operators (DNOs) issue regulations, which every site generating power must comply with. These regulations highlight the need for protection relays in order to protect the distribution network from dangerous effect of asynchronous generation and minimises the likelihood of equipment damage caused by disturbances coming directly from the mains network.

The importance of mains protection to Utility Companies

  • Ensures safe balanced operation of the distribution system
  • Guarantees reliable delivery of high quality electricity
  • Allows smooth involvement of the distributed generation
  • Enables remote control of power supply sources

The importance of mains protection to Plant Operators

With the responsibility for reliable protection of plant, operators must install and maintain adequate protection equipment. Protection settings at the interfaces between the network operator and the plant operator/connection owner is governed using country specific guidelines, whilst the network operator determines whether and which protection devices are to be sealed or otherwise protected against alterations*.

The plant operator then must ensure

  • Compliance with locally applicable standards and rules
  • Compliance with technical conditions on connection to the distribution network
  • Prevention of generator damage caused by grid parameters out of limits
  • Reduction of down time after generation disconnection / interruption

* extract from German standard BDEW


InteliMains NT

InteliMains NT BaseBox

InteliMains NTC BaseBox

MainsCompact NT




MainsPro LITE