M140 Series

Part of the 140 platform, the M140x feeder management relays provide an integrated solution for the complete protection, control and monitoring of overhead lines and underground cables, covering all distribution voltage levels.

Providing all essential information to efficiently maintain complex power systems and their components, the M140x relay family is user-friendly, allowing application on any electrical network.

The M140x is a feeder management relay platform with over current and earth fault protection, as well as auto reclose and a full suite of protection, control and monitoring functions.

The platform also provides main or back-up protection for MV, solidly earthed, and isolated neutral systems.

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Key benefits:

  • Full feeder management with efficient monitoring, control, recording and digital communications

  • Supports major digital control system protocols for integration into DCS, SCADA and engineering workstations.

  • Harsh environment protection extends the life of the product.


  • 3-stages of non-directional over current, earth fault, sensitive earth fault protection

  • Negative phase sequence over current, Broken conductor, Breaker fail protection.

  • Auto reclose & Cold Load Switching Feature.

  • TCS, CB Monitoring, Max Current Demand Supervision functions.

  • IEC 61850 with Rear FO Port, Modbus RTU or IEC60870-5-103 with RS 485 Rear Port for Remote Communication.

  • Front USB Port for User interface.

Special Application:

  • Auto reclose function offers multi shots reclosing to avoid discontinuity during transient fault tripping in transmission lines.

  • The standard curves offers reliable fault tripping, without constraining circuit loadability

  • Cold Load Switching feature avoids protection relay tripping due to inrush current, when a distribution circuit is re-energized following an extended outage.

Device Number Function
79 Auto reclose
86 Latching/Lockout Contacts
46BC Broken Conductor
50BF CB Failure
CLP Cold Load Pick Up
TCM Trip Circuit Monitor
50N Earth Fault Definitive Time Over current
51N Neutral/Ground IDMT Over current
SEF Sensitive Earth Fault
46 Negative Sequence Over current
50 Phase Definitive Time Over current
51 Phase Inverse-Time Over current
68 Inrush Blocking
CLP Cold Load Pick Up
TCM Trip Circuit Monitor
Three Phase & Earth Fault Over current protections With Three stages of settings- Low set, wide set, High set (True RMS measurement).

6 independent Characteristics for Phase and Earth Fault.

Settings with Password Protection.

16 Characters 2 Line LCD display with backlight- alphanumeric display

1Amp & 5 Amp CT secondary selectable by software

Aux Voltage: 24V, 30V, 48V, 110, 220 Vdc

DC transient free instantaneous High set with operating time <15 milliseconds @5times the setting. (Takes care of CT saturation)

Self Monitoring.

Secondary current values display.

Reset time feature for flashing faults.

Two group of protection settings.

Primary Metering.

Cold load Switching

Multi shot Auto reclose.

Trip circuit supervision.

Circuit Breaker failure protection.

Circuit Breaker monitoring.

External blocking feature.

Configurable Digital inputs.

Configurable Digital outputs.

Configurable dual color LED Indications.

Maximum current demand.

Feeder identification.

Relay test facility.

Communication: MODBUS- RS 485 Rear Port

Communication: IEC60870/103- RS 485 Rear Port

Communication: IEC60870/104- Ethernet Rear Port

Communication: IEC61850- FO Rear Port

User Interface USB Front Port


M140x PC STUDIO is a PC tool for configuring M140C and M140D relays that assemble all tools in a palette for simple entry, with intuitive navigation via fewer mouse-clicks.

Key benefits / features in the M140x PC STUDIO family

  •  Powerful free of charge PC interface tool
  •  Intuitive and versatile interface with file management facilities
  •  Parameterization facilities for IED settings
  •  Real-time measurement visualization
  •  Integrated configuration and monitoring features
  •  Send and extract setting files
  •  Event and disturbance record extraction and analysis