GE Multilin 745 Transformer Management Relay

These instructions are not intended to cover all details or variations in the equipment, nor do they provide whether installation, operation or maintenance requires further information or presents special problems

For the buyer, those not adequately covered shall refer to General Electric Company.

To the extent required, the products described herein comply with applicable ANSI, IEEE, and NEMA standards; however, with respect to local codes and ordinances, as they vary widely.

The 745 Transformer Protection System™ is a high-speed, multiprocessor-based three-phase, two-winding or three-winding transformer management relay.

for the protection and management of primary small, medium and large power transformers.

The 745 combines percentage differential, overcurrent, frequency and overexcitation protection elements as well as individual harmonic and total harmonic distortion (THD) monitoring in one economical package.

The relay offers a variety of adaptive relaying functions:

-Adaptive harmonic suppression, which resolves in inflow

-Adaptive time overcurrent element, which can be based on the harmonic content of the transformer capacity calculated when supplying high load currents

-Multiple set point groups that allow the user to enter and dynamically select from up to four relay settings to address different protection requirements for power system configurations

Dynamic CT ratio mismatch correction for monitoring on-load tap positions and automatically correcting CT ratio mismatches.

FlexLogic™ which allows PLC-style equations based on logic inputs and protections to be assigned to any of the 745's output elements.

The 745 also includes powerful test and simulation capabilities.

This allows protection designs to be based on captured or computer-generated relay operation test capability waveform data, which can be converted to a digital format and downloaded to the 745.

The 745's analogue buffer can be used for “playback”. The recorded waveform capture feature also provides waveform data for fault, surge or alarm conditions.

The auto-configuration feature eliminates the need for any special CT connections by eliminating the need for all CTs with Y-connections.