Overview - GE t60 Instruction Manual

2 PRODUCT DESCRIPTION
2 PRODUCT DESCRIPTION 2.1INTRODUCTION
The T60 Transformer Management Relay is a microprocessor-based relay for protection of small, medium, and large three-
phase power transformers. The relay can be configured with a maximum of four three-phase current inputs and four ground
current inputs, and can satisfy applications with transformer windings connected between two breakers, such as in a ring
bus or in breaker-and-a-half configurations. The T60 performs magnitude and phase shift compensation internally, eliminat-
ing requirements for external CT connections and auxiliary CTs.
The Percent Differential element is the main protection device in the T60. Instantaneous Differential protection, Volts-per-
Hertz, Restricted Ground Fault, and many current, voltage, and frequency-based protection elements are also incorpo-
rated. The T60 includes sixteen fully programmable universal comparators, or FlexElements™, that provide additional flex-
ibility by allowing the user to customize their own protection functions that respond to any signals measured or calculated
by the relay.
The metering functions of the T60 include true RMS and phasors for currents and voltages, current harmonics and THD,
symmetrical components, frequency, power, power factor, and energy.
Diagnostic features include an Event Recorder capable of storing 1024 time-tagged events, oscillography capable of stor-
ing up to 64 records with programmable trigger, content and sampling rate, and Data Logger acquisition of up to 16 chan-
nels, with programmable content and sampling rate. Diagnostic features include a sequence of records capable of storing
1024 time-tagged events. The internal clock used for time-tagging can be synchronized with an IRIG-B signal or via the
SNTP protocol over the Ethernet port. This precise time stamping allows the sequence of events to be determined through-
out the system. Events can also be programmed (via FlexLogic™ equations) to trigger oscillography data capture which
may be set to record the measured parameters before and after the event for viewing on a personal computer (PC). These
tools significantly reduce troubleshooting time and simplify report generation in the event of a system fault.
A faceplate RS232 port may be used to connect to a PC for the programming of settings and the monitoring of actual val-
ues. A variety of communications modules are available. Two rear RS485 ports allow independent access by operating and
engineering staff. All serial ports use the Modbus
with baud rates up to 115.2 kbps. The RS232 port has a fixed baud rate of 19.2 kbps. Optional communications modules
include a 10BaseF Ethernet interface which can be used to provide fast, reliable communications in noisy environments.
Another option provides two 10BaseF fiber optic ports for redundancy. The Ethernet port supports MMS/UCA2, Modbus
TCP, and TFTP protocols, and allows access to the relay via any standard web browser (UR web pages). The IEC 60870-
5-104 protocol is supported on the Ethernet port. DNP 3.0 and IEC 60870-5-104 cannot be enabled at the same time.
The T60 IEDs use flash memory technology which allows field upgrading as new features are added. The following Single
Line Diagram illustrates the relay functionality using ANSI (American National Standards Institute) device numbers.
Table 2–1: DEVICE NUMBERS AND FUNCTIONS
DEVICE FUNCTION
NUMBER
24 Volts Per Hertz
27 Phase Undervoltage
27X Auxiliary Undervoltage
50/87 Instantaneous Differential Overcurrent
50G Ground Instantaneous Overcurrent
50N Neutral Instantaneous Overcurrent
50P Phase Instantaneous Overcurrent
51G Ground Time Overcurrent
51N Neutral Time Overcurrent
51P Phase Time Overcurrent
GE Multilin
®
RTU protocol. The RS485 ports may be connected to system computers
DEVICE FUNCTION
NUMBER
59N Neutral Overvoltage
59P Phase Overvoltage
59X Auxiliary Overvoltage
67N Neutral Directional Overcurrent
67P Phase Directional Overcurrent
81O Overfrequency
81U Underfrequency
87G Restricted Ground Fault
87T Transformer Differential
T60 Transformer Management Relay
2.1 INTRODUCTION

2.1.1 OVERVIEW

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