745 Transformer Management Relay

The 745 is a high speed, multiprocessor based, 3-phase, two or three winding, transformer management relay intended for the primary protection and management of small, medium and large power transformers.

New in SR745:

• Fast, flexible and reliable communications - Embedded 10BaseT Ethernet capability provides faster data transfer thus improves system performance
• Reduce installation & maintenance cost - Fewer components to install, commission and maintain
• Simplified remote communication - Easy integration to Wide Area Network provides effortless remote access to the devices
• Unique Security Audit Trail feature provides fast and easy troubleshooting, improved maintenance procedures and increased device security - Viewpoint Maintenance 3.0 can generate Security History Report from the 745 and clearly maps out detailed description of device configuration changes
• Enhanced fault and disturbance analysis - Expanded (doubled) sequence of event recorder and waveform capture (256 time stamped events and up to 128 cycles of oscillography data at a sampling rate of 64 samples per power cycle)
• Increased ease of use - New features have been added to 745 Setup Program to quickly and easily complete 745 commissioning, testing and maintenance tasks (see 745 release notes for details)

• Unique Protection Features - Optimum transformer life expectancy, harmonic de-rating, advanced loss of life algorithm, THD monitoring, built-in winding adaptive overcurrent elements for backup protection
• Best in class man machine interface (MMI) - Large backlit display with 40 characters to view relay information and settings in direct sunlight, full numerical keypad, and setpoint navigation keys
• Accurate metering under sever system disturbances - Tracks power system frequency and adjusts sampling rate accordingly
• Flexible and cost effective control for complex systems - Use FlexLogic™ to customize the functionality of your transformer protection & control system to address unique, site specific applications
• Minimize replacement time - Draw-out construction
• Improve uptime of auxiliary equipment - Through I/O monitoring
• Reduce system event analyzing time and cost - Sequence of event reports, oscillography, data logging, IRIG-B time synchronization
• Simplified testing - Built in simulation features and waveform playback for relay setting verification
• Cost effective access to information - Via Modbus RTU and DNP 3.0 Level 2 protocols, through standard RS232, RS485 & RS422 serial ports, and optional Modbus RTU over TCP/IP through embedded Ethernet 10BaseT Port to connect to 10MB Ethernet local or wide area networks.
• Advanced current monitoring - Current metering including phase & ground, demand, sequence components, differential and restraint, and ground differential
• Industrially hardened - With optional harsh environment conformal coating when installed in chemically corrosive and humid environments

• Primary protection and management of small, medium and larger power transformers
• Up to 3 restraint windings

• Percent differential
• Adaptive harmonic restraint
• Multiple overcurrent elements
• Adaptive time O/C elements
• Underfrequency
• Frequency rate-of-change
• Overexcitation (V/Hz)
• 4 setpoint groups
• Restricted ground fault (optional)
• 1 analog transducer input (optional)
• 16 digital (logic) inputs
• 7 analog transducer outputs (optional)
• 9 control outputs

• All currents
• THD and harmonics
• Demand
• Harmonic analysis
• Voltage
• Calculated 3 Phase Power
• Tap position
• Ambient temperature
• Analog transducer input
• Event recorder
• Oscillography & Data Logger
• Oscillography playback

• Front Panel LEDs, full key pad, and backlit LCD display
• Ethernet port, 10Mbps
• RS232, RS485 and RS422 ports - up to 19,200 bps
• Multiple protocols - ModBus™ RTU, ModBus™ TCP/IP, DNP 3.0 Level 2
• Time synchronization via IRIG-B Port
• Includes EnerVista Software