Digital Differential Protection Relays

• GWPR350‑BD Busbar Differential Protection Relay is a 7‑bay numerical busbar differential protection device launched by GoWatron. Designed for 11‑33kV single‑bus non‑sectionalized unearthed neutral distribution systems, it supports up to 7 protection branches. Adopting a percentage biased differential algorithm, it integrates busbar differential protection, branch backup overcurrent protection, abnormal alarm, fault recording and multi‑interface communication. It can rapidly clear internal busbar short‑circuit faults and prevent station‑wide blackouts, delivering a reliable main‑protection solution for medium‑voltage distribution busbars.
• 2‑port 10/100M adaptive Ethernet (IEC 60870‑5‑103 supported, IEC 61850 optional)
• 1 port optically‑isolated RS485 (Modbus‑RTU)
• IRIG‑B time synchronization, enabling remote signaling, remote measurement and remote control.

• GWPR300‑GT Generator‑Transformer Unit differential Protection Relay is an integrated protection, measurement and control device launched by GoWatron specifically for generator‑transformer units. It is designed for small‑to‑medium‑size generator‑transformer units with capacity up to 10 MW (typical application scope; other capacities can be customized), compatible with generator‑transformer connections at voltage levels up to 132 kV. It supports both centralized panel‑mounted and decentralized field‑mounted deployment. It is mainly applied for relay protection and local / remote measurement‑control requirements of generator‑transformer units in self‑supply power plants and small‑scale power stations.
• Communication: Dual Ethernet ports support IEC 60870‑5‑104 / 103 protocols, IEC 61850 is optional; RS485 supports Modbus‑RTU.
• Time Synchronization: Supports IRIG‑B (DC code), SNTP, message‑based time synchronization and other time‑sync modes.

• The GWPR300-MI is a motor integrated differential protection relay developed by GoWatron. It is applicable to 0.4kV~13.8kV low and medium voltage asynchronous motors and compatible with various CT and PT connection configurations. It comprehensively covers fault protection under all motor operating conditions, real-time electrical quantity acquisition, remote monitoring and local commissioning, realizing integrated protection, measurement & control and communication functions.

The device is equipped with multiple independent communication interfaces:

• Dual Ethernet ports: Support IEC 104, IEC 61850 optional, meeting redundant networking requirements for intelligent substations;
• RS485 port: Standard Modbus-RTU, suitable for local cabinet monitoring.

The GWPR320-LD Fiber-Optic Line Differential Protection Relay is independently developed and manufactured by GoWatron, designed for power transmission and distribution lines rated at 66kV, 33kV and 10kV. It serves as the main protection device for overhead transmission lines, cable feeders and transformer outgoing feeders. The device supports flush mounting on local switchgears and centralized panel mounting in control rooms. It integrates fiber-optic current differential main protection, comprehensive directional phase and zero-sequence backup protection, multi-channel remote signal acquisition, electrical parameter measurement, fault recording, sequence-of-events (SOE) recording, multi-protocol communication and multi-mode time synchronization functions into a single compact unit.

Equipped with dual-Ethernet and dual-channel RS485 communication hardware, the device is fully compatible with various substation integrated automation systems.

• Standard Communication Protocols: IEC 60870-5-104, Modbus RTU. It supports full uploading of measured electrical values, remote signaling status, fault event records, fault recording files and protection setting parameters.
• Optional Communication Protocol: Full IEC 61850 standard protocol suite (supporting MMS and GOOSE profiles), which meets the networking requirements of digital intelligent 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 GWPR300-GD Generator Differential Protection Relay is mainly designed for differential protection of 10 MW hydro generators and steam turbine generators rated up to 100 MW. It is usually mounted on the same panel alongside the GWPR300-GRE Generator Rotor Earth Fault Protection Relay and GWPR300-GB Generator Back-up Protection Relay to form an integrated generator protection system.

• Communication;2× Ethernet (IEC 103/104) + 1× RS485 (Modbus-RTU). Optional: 2 extra Ethernet for IEC 61850.
• Time Sync；IEEE 1588 PTP, SNTP, IRIG-B.
• Fault Recording；128 protection/alarm/remote signals, 128 operation logs, 16 self-test logs, 32 fault waveforms (full timestamps & data).
• Measurement & Control；Monitors 3-phase electrical parameters. 21 DI, 13 relay outputs, 1 power-loss alarm output.