Beckwith M-3311A Transformer Integrated Protection Device

Beckwith M-3311A Transformer Integrated Protection Device

Beckwith M-3311A digital multi winding transformer protection device original factory complete operation manual, covering the entire process of hardware, protection logic, human-machine interface, upper software IPScom, communication, installation, setting, and on-site verification; The equipment is designed for 2/3/4 winding power transformers (main transformers, plant transformers, autotransformers) and can also be used for generator transformer sets, busbar protection, and feeder backup protection. It supports 50/60Hz systems and has 1A/5A CT secondary options, complying with IEEE and IEC power relay protection standards.

Hardware configuration and optional accessories

1. Standard hardware foundation

Sampling input: up to 4 sets of winding three-phase CT+grounded CT, up to 4 PT voltage inputs; Zero sequence grounding current dedicated acquisition circuit;

Control circuit: Standard configuration includes 6 programmable status inputs and 8 outputs (6 normally open+2 conversion); Optional expansion I/O (additional 12 inputs+8 outputs);

Communication ports: front panel COM1 RS232, backplane COM2 RS23, COM3 RS485; Optional RJ45 Ethernet; Support IRIG-B timing (BNC interface);

Storage: fault waveform recording, 8 sets of trip target records, 512 SOE records, ground fault statistics, overcurrent accumulation records;

Power supply: Wide AC/DC universal power supply, dual redundant power supply is standard for extended I/O models, and redundant power modules can be added for ordinary models;

Installation: Standard 19 inch rack, divided into standard height/extended I/O height, supports horizontal and vertical cabinet installation.

2. Optional supporting modules

M-3931 HMI local operation panel: 2-line 24 character LCD, three-level permission password, local view of measurement/modification of settings;

M-3911A Target Fault Indicator Module: 24 channel protection dedicated LED, visually distinguishing various fault actions;

S-3300 IPScom upper software: Windows remote tuning, waveform download, real-time phasor monitoring;

M-3801D IPSplot Plus waveform analysis software is used to analyze COMTRADE waveform files;

Dedicated communication cable, redundant high and low voltage power supply, serial port modem kit.

Complete protection function (ANSI standard numbering division)

Divided into two main modules: standard standard standard protection and optional voltage protection package, with built-in universal programmable logic IP Slow.

（1） Standard basic protection (all factory equipped)

46 Negative sequence overcurrent (2/3/4 winding independent configuration): timed/inverse time limit, to prevent rotor overheating caused by three-phase imbalance, phase failure, and asymmetric short circuit; Provide multiple sets of IEC/IEEE standard inverse time curves.

49 winding thermal overload protection: I ² t thermal accumulation model, single winding independent activation, monitoring transformer long-term overload heating.

50 instantaneous phase overcurrent (multiple independent components): short circuit quick break protection within the zone;

50G instantaneous grounding overcurrent: instantaneous grounding tripping inside the winding;

50N instantaneous residual overcurrent;

50BF circuit breaker failure protection: discrimination of circuit breaker failure in each winding, and tripping of adjacent switches after failure;

51 timed/inverse time overcurrent: phase to phase short circuit backup;

51G/51N inverse time grounding, residual overcurrent: grounding fault delay backup;

87T winding phase differential main protection: dual slope braking, built-in 2/4/5th harmonic blocking (to suppress excitation inrush current), equipped with 87H high-value instantaneous differential;

87GD grounding differential protection: internal grounding protection of neutral point grounding winding, capable of direction discrimination;

IPSigmic programmable logic: multiple sets of and/or/non delay logic to achieve load shedding, LTC voltage regulation locking, interlock tripping, and automatic switching of fixed values;

TCM trip circuit monitoring, CCM closing circuit monitoring (extended I/O exclusive);

BM circuit breaker wear monitoring: integrate I ² t to calculate arc loss, reach threshold alarm;

Through Fault records: Count the number of external short circuits, accumulate I ² t damage, and evaluate transformer insulation aging.

（2） Optional voltage protection kit (optional upon ordering)

24 V/Hz overexcitation protection (2 fixed time limits+1 reverse time limit to prevent iron core saturation)

27 three-phase undervoltage (multi-stage constant value, used for low-voltage load shedding)

59 phase overvoltage, 59G open delta zero sequence overvoltage (winding turn to turn, grounding monitoring)

81O/U four segment high and low frequency protection (unit islanding, system frequency abnormality)

Measurement, recording, and diagnostic functions

1. Real time measurement and monitoring

Three phase phase voltage, line voltage, and zero sequence voltage; Positive/negative/zero sequence current; Active, reactive, and power factors of each winding;

15/30/60 minute demand current, peak band time scale storage;

Real time graphical display of differential braking current, various harmonic currents, and 87T double slope curve;

Phasor diagram function, visually verifying CT/PT polarity and phase matching.

2. Four major record storage systems

Target Trip Record: Stores the complete information of the last 8 trips, including the operating components, time stamps, and current and voltage at the time of the fault;

SOE event sequence recording: 512 millisecond level time stamps, recording input displacement, protection start, trip, and communication status;

Through Fault Fault Recorder: Independently records the number of external short circuits, duration, and cumulative I ² t;

Fault Oscillograph: 16 times power frequency sampling, supports 1-24 partition storage, saves waveforms before and after faults, exports to standard COMTRADE format, can be analyzed by IPSlot software; Loss of waveform data due to power outage.

3. Whole machine self diagnosis

Power on self-test, real-time hardware monitoring, and fault codes are output through flashing DIAG indicator lights; The verification code and software and hardware versions can be viewed locally through HMI or on the upper level.

Human machine operating system: local HMI+IPSgom upper software

1. M-3931 local HMI panel

Third level access permissions (1 read-only/2 adjustable value/3 system configuration), customizable 4-digit access password;

Menu hierarchy: measurement status, fault record, waveform recording, constant value setting, system configuration, communication, clock, user-defined identifier;

Support viewing phasor, differential braking curve, cumulative wear of circuit breakers, and maximum required current;

Four independent constant value zones can be manually switched to adapt to different working conditions of transformer no-load/load, grid connected/offline.

2. S-3300 IPScom computer software (core operation and maintenance tool)

Complete functional menu: file management, communication connection, real-time monitoring, relay settings, tool settings;

Monitoring interface: primary/secondary measurement, harmonic, differential curve, I/O status, phasor vector diagram;

Fixed value management: read, write, compare, save fixed value files, and batch distribute devices;

Record operations: download SOE, fault target, traverse fault, record waveform;

Communication configuration: serial port/Ethernet/modem parameters, protocol (Modbus/DNP3/IEC61850);

Auxiliary tools: output testing, firmware upgrade, device calibration, access code modification.

Complete specifications of communication system

physical interface

COM1: Front panel RS232 (local debugging);

COM2: Backplane RS232, turn off after enabling Ethernet;

COM3: Backplane 2-wire RS485 bus (multi device networking);

Optional RJ45 network port; IRIG-B time scale BNC;

Supported protocols: Modbus RTU/TCP, DNP3.0, BECO2200, optional IEC 61850;

Clock synchronization: IRIG-B modulation/demodulation signal, with millisecond time scale to unify all events;

Networking capability: Up to 32 units of the same series of protection can be mounted on the RS485 bus.

System configuration and tuning system

1. Four independent fixed value zones

The device has 4 sets of complete fixed values built-in, with switching modes: HMI manual, upper communication, and external passive contact triggering; Support copying any fixed value area to other partitions.

2. System basic settings items

Number of windings (2/3/4 windings), CT/PT ratio, transformer wiring group (Y/D/autotransformer standard/custom phase compensation), phase sequence, zero sequence filtering on/off, output pulse/self hold mode, monitoring of closing and tripping circuits, number of recording zones, trigger source configuration.

3. Protect the setting parameter specifications

Each protection provides adjustable starting value, delay, curve selection, and output contact allocation; Differential protection supports dual slope and multi order harmonic braking threshold; All functions support separate switching and flexible selection of protection configurations.

Mechanical, Environmental, and Safety Standards

Installation: Standard 19 inch rack, divided into regular I/O (3U) and expansion I/O (4U), providing horizontal/vertical opening drawings;

Environment: Operating temperature -20 ℃~+70 ℃, storage -65~+100 ℃, 95% non condensing humidity; Meet IEC vibration and impact tests;

Insulation and EMC: 2kV power frequency withstand voltage, 5kV impulse withstand voltage; Electrostatic 8kV air/4kV contact, electric fast pulse 4kV, RF radiation anti-interference; Class A radiation emission;

Certification: UL508, CSA, CE, compliant with IEC 60255 General Standard for Relay Protection;

Contact capacity: 250Vdc short-term 30A connection, long-term 8A load, meets the requirements of trip circuit capacity.

Wiring, installation, and on-site testing

Terminal definition: distinguish between CT, PT, status input, trip/alarm output, communication IRIG‑B； Provide standard primary and secondary wiring diagrams for 2/3/4 windings;

Construction specifications: CT secondary must not be open circuited, PT secondary must be reliably grounded; Pull out the plug-in protection device before the pressure test;

Whole machine verification chapter: divided into hardware self-test, input/output testing, independent simulation verification steps for each protection, supporting standard testing circuits, and allowable error ranges;

Maintenance: No regular disassembly and maintenance, only periodic protection transmission tests; Replace the circuit board of the faulty machine.