M-3425A Comprehensive Generator Relay

Integrated Protection System for Generators of All Sizes.

  • Exceeds IEEE C37.102 and Standard 242 requirements for generator protection
  • Protects generators of any prime mover, grounding and connection type
  • Provides all major protective functions for generator protection including:
    • Out‑of‑Step (78)
    • Split‑Phase Differential (50DT)
    • Under Frequency Time Accumulation (81A)
    • Inadvertent Energizing (50/27)
    • Turn‑to‑Turn Fault (59X)
  • Expanded IPScom® Communications Software provides simple and logical setting and programming, including logic schemes
  • Simple application with Base and Comprehensive protection packages
  • Load encroachment blinders and power swing blocking for system backup protection (21) to enhance security during system abnormal conditions
  • Options:
    • Ethernet Connection
    • Field Ground/Brush Lift‑Off Protection (64F/B)
    • 100% Stator Ground Fault Protection by low frequency injection (64S)
    • Expanded I/O (15 additional Output Contacts and 8 additional Control/Status Inputs)

Standard Control Features

Base Package

  • Overexcitation (V/Hz) (24)
  • Phase Undervoltage (27)
  • Directional power sensitive triple‑setpoint Reverse Power, Low Forward Power or Overpower detection, one of which can be used for sequential tripping (32)
  • Dual‑zone, offset‑mho Loss of Field (40), which may be applied with undervoltage controlled accelerated tripping
  • Sensitive Negative Sequence Overcurrent protection and alarm (46)
  • Instantaneous Phase Overcurrent (50)
  • Inadvertent Energizing (50/27)
  • Generator Breaker Failure (50BF)
  • Instantaneous Neutral Overcurrent (50N)
  • Inverse Time Neutral Overcurrent (51N)
  • Three‑phase Inverse Time Overcurrent (51V) with voltage control and voltage restraint.
  • Phase Overvoltage (59)
  • Neutral Overvoltage (59N)
  • Multi‑purpose Overvoltage (59X)
  • VT Fuse‑Loss Detection and blocking (60FL)
  • Residual Directional Overcurrent (67N)
  • Four‑step Over/Underfrequency (81)
  • Phase Differential Current (87)
  • Ground (zero sequence) Differential Current (87GD)
  • IPSlogic takes the contact input status and function status and generates outputs by employing (OR, AND, and NOT) boolean logic and a timer.

Comprehensive Package

  • The Comprehensive Package includes all Base Package functions, as well as the following:
  • Three‑zone Phase Distance protection for phase fault backup protection (21). Zone three can be used for Out‑of‑Step Blocking. Load encroachment blinders can be applied.
  • Sync Check with Phase Angle, ∆V and ∆F with dead line/dead bus options (25)
  • 100% Stator Ground Fault protection using Third Harmonic Neutral Undervoltage (27TN) or (59D) Third Harmonic Voltage Differential (ratio)
  • Stator Overload (49) (Positive Sequence Overcurrent)
  • Definite Time Overcurrent (50DT) can be used for split phase differential
  • Out‑of‑Step (78)
  • UnderFrequency Accumulation (81A)
  • Rate of Change of Frequency (81R)

Optional Features

  • Field Ground (64F) and Brush Lift Off (64B) (Includes M‑3921 Field Ground Coupler)
  • 100% Stator Ground protection by low frequency injection (64S). The following equipment is required with the 64S option:
    • 20 Hz signal generator (430‑00426)
    • Band Pass Filter (430‑00427)
    • 400/5 A 20 Hz CT (430‑00428)

B-1347 External 20 Hz Generator, Bandpass Filter, and 400:5A CT (64S) Surface or Flush Mount

M-0331 PT Transformer – 240:120 Volt
(Required when 20Hz generator is supplied with 1-phase 220Vac)

M-0423 10′ RS 232 Serial Null-Modem Cable

M-0433 10′ USB to Serial Adapter with RS 232 Serial Null-Modem Cable

M-3904B Remote Monitoring Module

M-3908 Universal Contact Input Adapter

M-3921 Field ground (64F) External Coupler Module

M-3926 25′ Universal Connecting Cable TIA-232/485

M-3933 10′ TIA-232 Serial Modem Cable