MiCOM Alstom P541, P542

MiCOM Alstom P541/P542 series provide high-speed current differential unit protection. The P541, P542 are designed for all overhead line and cable applications, interfacing readily with the longitudinal (end-end) communications channel between line terminals. The interface options support direct fibre optic or multiplexed digital links.

Optimum selectivity is assured, as the scheme measures the currents entering and leaving the protected plant item. Instantaneous tripping results for an internal fault, with stability for any out-of-zone fault. Tripping uses a proven characteristic comparing differential current with through current, for ease of testing. Phase differential elements of this type offer consistent detection of solid and resistive faults, with optimum faulted phase selection, tripping, and indication. 

Basic description:

  • Line differential protection with overcurrent backup protection and autoreclose
  • Application fields: distribution lines and cables

Key customer benefits:

  • Phase segregated differential with proven biased characteristic for distribution/sub-transmission networks
  • Graphical programmable scheme logic (PSL) eases protection scheme creation, and avoids the need for external logic controllers
  • Comprehensive communication optionsIdeal relay for the step from pilot wire to fibre or multiplexed end-end communications

Main characteristics:

  • Differential protection adaptable to different substation topologies: e.g. 2 or 3 terminal lines/cables, in-zone transformers, 3 pole tripping
  • Choice of communication protocols (IEC 60870-5-103, Modbus & Courier)
  • Time synchronisation via RS485, IRIG-B (modulated/unmodulated) or opto inputs
  • Harsh environment option to protect against corrosive gases such as H2S or SO2
  • 4 independent setting groups

Overall differentiation factors:

  • Feeders with in-zone transformers
  • Harsh environment protection extends the life of the product
  • An ideal economy solution for distribution applications
  • Small case width eases retrofitting tasks

Models Available:

  • P541 Line-Differential Protection IED
  • P542 Line-Differential Protection IED with Autoreclose

About MiCOM P40 Agile

Alstom’s philosophy is one of continuous improvement in our products and solutions.  Our emphasis on communication in MiCOM has become a focus which secures leadership in the digital substation.  To mark this phase of evolution, the brand “P40 Agile” is applied to the range.  P40 Agile is a mark of performance and quality, proudly available from Alstom, and only from Alstom.