Description
WOODWARD
TYP: XD1T55SAT
TRANSFORMER DIFFERENTIAL PROTECTION RELAY
XD1-T
UV: 35-275 VAC 19-390 VDC
FN: 50-60 HZ
IN: 5/5A
The Woodward XD1-T is a transformer differential protection relay designed to detect internal faults within power transformers by continuously monitoring current balance across transformer windings. When a fault condition such as a winding short, turn-to-turn fault, or insulation breakdown is detected, the relay operates rapidly to isolate the affected transformer, preventing escalation to wider switchboard or distribution failures. As a core component within a marine control system, this relay plays a critical role in safeguarding onboard power generation and distribution infrastructure, helping maintain electrical continuity and vessel safety during normal and abnormal operating conditions.
Key Features
✓ Differential protection function continuously compares current on both sides of the transformer winding to detect internal fault conditions with high sensitivity.
✓ Wide auxiliary supply range of 35–275 VAC and 19–390 VDC makes the unit adaptable across varied onboard power supply configurations; current input rated at 5/5A with frequency compatibility of 50–60 Hz.
✓ Suitable for integration within marine switchboard panels, power management systems, and transformer protection assemblies — specific panel or controller compatibility subject to confirmation based on vessel configuration.
✓ Designed for installation within protected electrical enclosures typical of engine room switchboards and main distribution panels; compliance with specific classification society requirements should be confirmed against vessel documentation.
✓ As a direct replacement or retrofit unit, the XD1T55SAT should be verified against existing relay socket type, trip output configuration, and current transformer ratios prior to installation to ensure correct system integration.
Marine Applications
✓ Main and emergency switchboard transformer protection on commercial cargo vessels, tankers, and bulk carriers where continuous power availability is operationally critical.
✓ Power distribution systems aboard offshore support vessels, platform supply vessels, and drilling units requiring high-integrity transformer fault isolation.
✓ Generator step-up and step-down transformer protection in vessels with complex power generation arrangements including shaft generators or multiple diesel-electric sets.
✓ Retrofit protection upgrades on older tonnage where legacy relay technology is being replaced to improve fault discrimination and response reliability.
✓ Passenger vessels and RoPax ferries where transformer fault protection is integral to maintaining SOLAS-compliant emergency power availability and reducing fire risk from electrical faults.
Why Marine Engineers Choose
The Woodward XD1-T series is a recognised solution in marine power protection, valued for its wide supply voltage tolerance, reliable differential fault detection, and suitability across diverse transformer configurations found in commercial and offshore fleets.
Ideal For
Cargo vessels, tankers, bulk carriers, offshore support vessels, drilling units, passenger ships, RoPax ferries, and any commercial vessel requiring dependable transformer differential protection within the main or emergency power distribution system.
Technical Support & Compliance
Technical assistance is available for troubleshooting, commissioning, and integration of this relay into existing marine power protection schemes. Support can be provided remotely or coordinated for onboard assistance depending on vessel location and scope of work. For retrofit or upgrade projects, engineering review of existing protection settings and current transformer ratios is recommended prior to installation. To confirm compatibility and suitability for your specific application, please share nameplate photographs, existing relay part numbers or drawings, switchboard manufacturer and model details, current transformer ratios, vessel name, IMO number, and the intended scope of work. All compatibility confirmations are subject to technical review.
