DDS Digital Transformer Protection High-speed, three-phase differential protection for transformer faults. ■ Multiple, configurable digital l/Os ■ Transformer configuration selection ■ Software winding connection compensation ■ Enhanced capabilities to ease servicing ■ GE-NESIS Windows®-based programming ■ High-speed differential and backup instantaneous differential three-phase protection functions for power trans- formers with two, three or four windings I enerVista.com compatible (see page 275) ■ Current differential protection ■ Dual-slope percentage restraint ■ Event and oscillography recording User Interfaces ■ 20 character keypad, alphanumeric two- ■ RS232, RS485, plastic or glass fiber optic ■ ModBus® communication protocol available

DTP DDS Digital Transformer Protection Protection and Control The DTP is a digital relay that provides high-speed differential and backup instantaneous differential three-phase protection for power transformers with two, three or four windings. Differential Protection For high-magnitude external faults, the DTP uses a current differential with percentage restraint to compensate for unbalance caused by variation in CT outputs. The DTP differential unit has programmable dual-slope percentage restraint with adjustable slope breakpoint. Discrete Fourier Transformation (DFT) provides excellent frequency...

DTP DDS Digital Transformer Protection record has a maximum capacity of 66 cycles. The number of prefault cycles can be selected from two to 10 cycles. Each of the records includes the following information: I Instantaneous values for current A keypad and display allow local communication. Self-Checking Functions Self-checking functions at startup and during normal operation will block operation if an error is detected. Additionally, the TARGET RESET button allows testing of LED. Setting Tables The DTP has three independent setting tables, stored in nonvolatile memory. Only one table may be active...

DTP DDS Digital Transformer Protection The communications protocol requires the use of the GE-LOCAL software to facilitate communication with different protection systems. It guarantees efficient data transfer (especially for oscillography and other large files) along with error detection and automatic communication recovery. I GE-INTRO enables the user to con- Two Windows -based software packages are included with the DTP: I GE-LOCAL enables the user to ® As an option, GE-OSC software enables the user to study the oscillography records. visualize the protection settings, alarms, LEDs, measurements...

DTP DDS Digital Transformer Protection DTP Technical Specifications PROTECTION General settings: Frequency: Winding CT ratio: Protection settings: Winding tap: Winding configuration: Winding time group: Winding CT configuration: Differential function settings: Sensitivity: K1 percentage restraint: K2 percentage restraint: K1 – K2 inflexion: 2nd harmonic restraint: 5th harmonic restraint: 87B tap: COMMUNICATIONS Mode: Half duplex Speed: 1200 to 19200 bps Physical media: RS232 (ports 1, 3) RS485 (port 2 optional) Plastic fiber optic (port 2 optional) Type of connector: HFBR-4516 Power supplied:...