Description

The BECKWITH M-3425A-CS6SFS5HHA1TH0H10 is a high-end, multifunction generator protection and control relay engineered specifically for the comprehensive safeguarding of synchronous generators in utility-scale and industrial power generation applications. As part of Beckwith Electric’s flagship M-3425A series, this model integrates over 50 protection functions—including 100% stator ground fault detection, loss-of-excitation, out-of-step, reverse power, and vector shift—into a single, ruggedized platform compliant with IEEE C37.102 standards for generator protection.

Designed for hydroelectric, gas turbine, steam turbine, and diesel-driven generators up to 800 MVA, the BECKWITH M-3425A-CS6SFS5HHA1TH0H10 goes beyond conventional relaying by incorporating advanced automation features such as automatic synchronization, voltage regulation interface, and real-time synchrophasor measurement (IEEE C37.118). The unit includes a full-color touchscreen HMI for local monitoring, configuration, and diagnostics, eliminating the need for external software during commissioning. With dual Ethernet ports supporting Modbus TCP, DNP3, and IEC 61850 (optional), the M-3425A-CS6SFS5HHA1TH0H10 seamlessly integrates into modern SCADA and substation automation systems while maintaining backward compatibility with legacy control schemes.

Technical Specifications

Main Features and Advantages

100% stator ground fault protection with dual-method validation:
The BECKWITH M-3425A-CS6SFS5HHA1TH0H10 uniquely combines third-harmonic voltage differential and low-frequency injection (LFV) techniques to detect ground faults anywhere in the stator winding—even at the neutral point. This dual-scheme approach eliminates blind zones and provides fail-safe coverage critical for large generators where undetected ground faults can escalate to catastrophic phase-to-phase failures.

Integrated generator automation suite:
Beyond protection, the M-3425A-CS6SFS5HHA1TH0H10 functions as a complete generator controller. It performs auto-synchronization with live bus, monitors synchronism check parameters, interfaces directly with excitation systems via 4–20 mA or discrete signals, and executes load-sharing logic in parallel generator setups. Its built-in metering (kW, kVAR, PF, MWh) reduces the need for external meters, lowering system cost and complexity.

Advanced situational awareness and cyber resilience:
Equipped with a high-resolution touchscreen, the BECKWITH M-3425A-CS6SFS5HHA1TH0H10 displays real-time phasor diagrams, sequence components, and oscillography without requiring a laptop. It records up to 128 fault events with pre- and post-fault waveforms and streams synchrophasor data for wide-area monitoring. All communication stacks are hardened against cyber threats, featuring encrypted configuration backups and secure remote access—ensuring compliance with NERC CIP and evolving grid codes.

Modular hardware for future readiness:
The M-3425A-CS6SFS5HHA1TH0H10’s architecture supports field-upgradable I/O modules and communication cards. Whether adding fiber-optic links for pilot protection or expanding binary I/O for breaker control, the platform adapts without full replacement. Its robust metal chassis and conformal-coated PCBs ensure reliability in high-humidity, dusty, or corrosive environments typical of hydro plants or islanded microgrids.

Application Field

The BECKWITH M-3425A-CS6SFS5HHA1TH0H10 is the protection solution of choice for independent power producers (IPPs), municipal utilities, and industrial facilities operating medium- to large-scale synchronous generators. In hydroelectric plants, it protects Francis or Kaplan turbines with sensitive stator ground and overspeed backup functions, while its rugged design withstands high ambient humidity and temperature swings. For combined-cycle gas turbine (CCGT) facilities, the M-3425A-CS6SFS5HHA1TH0H10 provides coordinated protection during black-start sequences and islanded operation, including vector shift and rate-of-change-of-frequency (ROCOF) detection.

In mining and petrochemical complexes with on-site cogeneration, the BECKWITH M-3425A-CS6SFS5HHA1TH0H10 safeguards steam turbine generators tied to process steam systems, ensuring rapid isolation during internal faults while minimizing false trips during load transients. Renewable energy integrators also deploy this relay in biomass and waste-to-energy plants, where generator stability during fuel variability demands adaptive protection logic. Additionally, the M-3425A-CS6SFS5HHA1TH0H10 is frequently used in military bases and data centers with critical backup generation, where NERC compliance, cybersecurity, and autonomous operation are non-negotiable. Its ability to function as both protector and controller makes it ideal for microgrids seeking simplified architecture without sacrificing reliability.

Related Products

M-3425A-CS6SFS5HHA1TH0H00: Base variant without HMI touchscreen; requires external configuration tool
M-3425A-CS6SFS5HHA1TH1H10: Enhanced version with additional analog outputs for AVR interfacing
M-3420: Legacy generator relay predecessor; M-3425A offers superior processing and I/O density
M-6300: Beckwith’s transmission line protection IED; shares platform architecture but optimized for feeders
SEL-400G: Competitor generator relay from Schweitzer Engineering Laboratories; common cross-reference
B30: GE Multilin equivalent; used in similar applications but with different protocol emphasis
M-3450: Beckwith’s bus differential protection relay; often deployed alongside M-3425A in generator switchyards

Installation and Maintenance

Pre-installation preparation: Prior to installing the BECKWITH M-3425A-CS6SFS5HHA1TH0H10, confirm CT/VT ratios, polarity, and burden ratings match the application. Mount the unit in a ventilated 19″ rack with adequate clearance for airflow and cable management. Use shielded, twisted-pair cables for all analog and communication wiring, grounding shields at the relay end only. Connect CT secondaries through shorting blocks before termination to prevent open-circuit hazards. Verify that the station battery supply meets the 125 VDC or 240 VDC control voltage requirement specified in the order code.

Maintenance recommendations: The BECKWITH M-3425A-CS6SFS5HHA1TH0H10 features self-diagnostics for internal hardware, power supplies, and communication links—accessible via the touchscreen or remote protocols. Perform annual functional testing using a three-phase relay test set to validate trip times and logic coordination. After any system disturbance, download event reports and oscillography for performance review. Firmware updates should be applied only after validation in a test environment, using Beckwith’s official update package with digital signature verification. Store configuration backups securely with encryption, and rotate spare units every 5 years if held in long-term inventory to preserve capacitor integrity.