Digital Transformer Protection Relay

• The GWPR300-TNE Transformer Non-Electrical Quantity Protection Relay is designed for transformers rated up to and including 132 kV. Built on a high-performance 32-bit microcontroller platform with an integrated DSP and FPU, the relay provides protection processing, output logic, event recording, disturbance recording, and communication with substation supervisory systems. It continuously acquires and evaluates non-electrical quantity signals from the transformer main tank and on-load tap changer and initiates the corresponding trip or alarm outputs.
• The relay is primarily intended for transformer non-electrical quantity protection applications. It can receive signals associated with Buchholz alarm, Buchholz trip, temperature, cooling-system failure, pressure-relief device operation, oil level, and other non-electrical conditions. Trip or alarm outputs are initiated according to the configured logic and time-delay settings to help ensure safe and stable transformer operation.
• The relay supports two Ethernet ports using IEC 60870-5-104, two optional Ethernet ports using IEC 61850, and one RS-485 communication port using Modbus RTU. Supported time-synchronization methods include communication-message synchronization, SNTP, and IRIG-B. The relay also supports a serial dot-matrix printer for printing setting values and event records.

The GWPR200-T is a digital transformer protection relay designed for power systems rated up to 33 kV. It integrates protection, measurement, control, communication and fault recording functions.It can be installed in a centralized protection panel or locally in a switchgear cubicle.

• The relay supports RS-485 with Modbus RTU,
• optional dual Ethernet ports with IEC 60870-5-103 over Ethernet,
• and time synchronization via communication messages, SNTP or IRIG-B.

GoWatron GWPR300‑TB transformer backup protection relay is designed for transformers with 33kV‑132kV voltage classes. Select GWPR300‑THB for high‑voltage side and GWPR300‑TLB for low‑voltage side. It enables flexible backup protection configuration for high‑, medium‑ and low‑voltage sides of transformers, integrating protection, measurement & control, communication and fault recording functions. Equipped with a 32‑bit high‑performance MCU and DSP floating‑point arithmetic unit, it adopts 16‑bit high‑precision AD sampling. Featuring modular hardware design and galvanic isolation between strong and weak circuits, it delivers excellent EMC performance, adapting to harsh substation environments with high temperature and severe electromagnetic interference. It provides comprehensive fault protection and real‑time data acquisition & monitoring for power transformers.

• Communication: Dual Ethernet ports and RS‑485 interface; supports IEC‑104, Modbus‑RTU protocols, with optional IEC61850 (MMS).
• Time Synchronization: IRIG‑B code time synchronization, SNTP network time synchronization.
• Supports external printer for outputting protection settings, event reports and fault recording files.

• The GWPR100-I digital integrated protection relay is independently developed by GoWatron. It adopts a 32-bit embedded microprocessor architecture that integrates protection, measurement, control and communication functions into one single unit. The device is especially suitable for protection applications in ring main units and package substations. It applies to medium and low voltage distribution systems with rated voltages up to 11 kV and 13.8 kV, covering feeders, distribution transformers, shunt capacitor banks, bus tie breakers and asynchronous motors.
• This relay complies with IEC and GB EMC standards. It supports cyclic storage of 128 fault event logs and 8 groups of non-volatile setting groups, and is equipped with a Chinese LCD human-machine interface. Two installation modes are available: decentralized mounting on local switchgear panels and centralized rack mounting in control rooms, making it suitable for complex operating conditions of industrial plants, photovoltaic power stations and substations.

Independently developed and manufactured by GoWatron, the GWPR300-TD Transformer Differential Protection Relay is specially designed as the main protection for two-winding and three-winding power transformers with a voltage class of 132 kV and below. It supports both on-site cabinet mounting and centralized panel mounting in control rooms, integrating transformer differential main protection, non-electrical quantity acquisition with independent hardware tripping output, three-side current measurement, fault recording, sequence-of-event recording, multi-protocol communication and clock synchronization into a single unit.

• Equipped with dual Ethernet ports and RS485 dual communication channels, the relay is compatible with all types of substation integrated automation systems.
• Standard communication protocols: IEC 60870-5-104 and Modbus RTU, which support the upload of measured values, status signals, fault events, fault recording files and protection setting parameters.
•  Optional communication protocol: IEC 61850 (supports MMS and GOOSE), meeting the networking requirements of intelligent digital substations.

The GWPR350-TF is a multifunctional IED that combines transformer protection, measurement & control, and protocol gateway capabilities. It provides dedicated trip protection for the box-type substation, aggregates data from combiner boxes, inverters, and video surveillance systems, and forwards it to the SCADA system. With support for both on-site control and remote supervision, it ensures maximum security and stability for renewable energy.

• Features 2 self-healing optical-fiber interfaces and 3 self-healing electrical ports for optical-fiber ring-network formation.
• 2 CPU-integrated Ethernet communication interfaces.
• 2 CPU-integrated RS485 communication ports.
•  Supports communication protocols including Modbus, IEC 60870-5-103, IEC 60870-5-104, with IEC 61850 as an optional protocol.
• Protocol conversion: Fitted as standard with 10 RS485 interfaces and 2 Ethernet communication interfaces to function as a communication manager.

The GWPR300-TI Transformer Integrated Protection Relay is designed primarily for transformers of 132kV, 66kV, 33kV and 11kV voltage classes with a rated capacity of 10,000 kVA or less.

It incorporates all functions of one GWPR300-TD Transformer Differential Protection Relay plus all functions of one GWPR300-THB Transformer Backup Protection Relay. Integrating main and backup protection into a single device, it delivers the full capabilities of two separate relays in one unit.

• Interfaces: 2 × Ethernet, 2 × RS485 (the second RS485 port is shared with the time sync port, selectable via configuration).
• Protocols: IEC 103, IEC 104, Modbus RTU; IEC 61850 (optional).
• Time Synchronization: SNTP, IRIG-B, and message-based time sync.
• Printing: Supports serial dot-matrix printers for output of setting parameters, event logs, and fault waveform records.