Beckwith Electric M-3311A Transformer Protection (2, 3, or 4-Winding) Relay

• For Transformers of All Sizes:

 • Two-, Three- or Four-winding Transformers for Transmission and

Distribution applications

 • Generator-Transformer Unit Overall Differential

 • Unit Protection of Other Electrical Apparatus and

certain Bus Arrangements (including those with a transformer in

the zone)

• Additional Applications: System Backup Protection, Load Shedding

(voltage and frequency), Bus Protection, and individual Breaker

Failure Protection for each winding input

• Available voltage configurations include zero, two or four voltage inputs

• Ground Differential configurations include one, two or three current

inputs

• Optional Ethernet Connection and Expanded I/O

• Optional Voltage Package includes, 24 Volts/Hz Overexcitation, 27

Phase Undervoltage, 59G Ground Overvoltage and 81O/U Over/Under

Frequency

Standard Protective Functions

• Negative-sequence inverse time overcurrent (46)

• Winding thermal protection (49)

• Four-winding instantaneous phase overcurrent (50)

• Breaker Failure (50BF)

• Instantaneous ground overcurrent (50G)

• Instantaneous residual overcurrent (50N)

• Four-winding inverse time phase overcurrent (51)

• Inverse time ground overcurrent (51G)

• Inverse time residual overcurrent (51N)

• Two, three or four-winding phase differential (87T) and high set

instantaneous (87H)

• Ground differential (87GD)

• IPSlogic®

Optional Voltage Protection Package

• Overexcitation (24) V/Hz, two definite time and one inverse time

elements

• Phase Undervoltage (27) function for load shedding

• Phase Overvoltage (59)

• Ground Overvoltage (59G)

• Over/Underfrequency (81O/U)

Standard Features

• Target Module

• Human-Machine Interface (HMI) Module

• Eight programmable outputs and six programmable inputs

• Oscillographic recording

• Through-Fault Monitoring

• 8-target storage

• Real time metering of measured and calculated parameters,

including demand currents

• Two RS-232 and one RS-485 communications ports

• Standard 19" rack-mount design

• Removable printed circuit board and power supply

• 50 and 60 Hz models available

• 1 or 5 A rated CT inputs available

• S-3300 IPScom® Communications Software

• IRIG-B time synchronization

• Sequence of Events Log

• Breaker Monitoring

• Multiple Setpoint Groups

• Trip Circuit Monitoring

• Includes MODBUS and DNP 3.0 protocols

• Summing Currents from multiple sources for 49. 50. 51. 50N,

51N, 87 GD and Through Fault functions

Optional Features

• Redundant Power Supply

• Ethernet Port RJ-45 10/100 Base-T (MODBUS over TCP/IP)

• Ethernet Port RJ-45 10/100 Base-T (DNP over TCP/IP)

• Serial Port TIA-232 with RJ-45 Connector (DNP)

• Serial Port TIA-485 with RJ-45 Connector (DNP)

• Ethernet Port RJ-45 10/100 Base-T (IEC 61850 Protocol)

• M-3801D IPSplot® Plus Oscillograph Analysis Software

• Expanded I/O (8 additional outputs and 12 additional inputs)

• Standard and Expanded I/O Models available in vertical panel mount

• Close Circuit Monitoring on Expanded I/O units