GE UR T60, Instruction Manual

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GE Multilin T60 Transformer Protection System 5-79
5 SETTINGS 5.4 SYSTEM SETUP
5
The T60 Transformer Protection System has been designed to provide primary protection for medium to high voltage power
transformers. It is able to perform this function on 2 to 5 winding transformers in a variety of system configurations.
b) GENERAL TRANSFORMER SETTINGS
PATH: SETTINGS

SYSTEM SETUP

TRANSFORMER

GENERAL
The general transformer settings apply to all windings. Settings specific to each winding are shown in the following section.
• NUMBER OF WINDINGS : Selects the number of windings for transformer setup.
• REFERENCE WINDING : When set to Automatic Selection, a CT ratio mismatch can occur in firmware versions up to
7.1x that can cause signal clamping and misoperation on the differential element. To avoid this, manually select the
winding as outlined in the T35/T60 Reference Winding Selection and CT Ratio Mismatch Application Note (document
GET-8548). For releases subsequent to 7.1x, contact GE Digital Energy to inquire if this applies.
• PHASE COMPENSATION : Selects the type of phase compensation to be performed by the relay. If set to “Internal
(software)”, the transformer phase shift is compensated internally by the relay algorithm. If set to “External (with CTs)”,
the transformer phase shift is externally compensated by the CT connections.
• LOAD LOSS AT RATED LOAD : This setting should be taken from the transformer nameplate. If not available from the
nameplate, the setting value can be computed as , where is the winding rated current and R is
the three-phase series resistance. The setting is used as an input for the calculation of the hottest-spot winding tem-
perature.
• RATED WINDING TEMP RISE : This setting defines the winding temperature rise over 30°C ambient temperature. The
setting is automatically selected for the transformer type as shown in the table below.
MESSAGE

WINDING 4

See page 5–81.
MESSAGE

WINDING 5

See page 5–81.
MESSAGE

THERMAL INPUTS

See page 5–90.

GENERAL

NUMBER OF WINDINGS:
2
Range: 2 to 5 in steps of 1
MESSAGE
REFERENCE WINDING:
Automatic Selection
Range: Automatic Selection, Winding 1, Winding 2,...,
Winding 5
MESSAGE
PHASE COMPENSATION:
Internal (software)
Range: Internal (software), External (with CTs)
MESSAGE
LOAD LOSS AT RATED
LOAD: 100 kW
Range: 1 to 20000 kW in steps of 1
MESSAGE
RATED WINDING TEMP
RISE: 65°C (oil)
Range: 55°C (oil), 65°C (oil), 80°C (dry), 115°C (dry),
150°C (dry)
MESSAGE
NO LOAD LOSS:
10 kW
Range: 1 to 20000 kW in steps of 1
MESSAGE
TYPE OF COOLING:
OA
Range: OA, FA, Non-directed FOA/FOW, Directed FOA/
FOW, Sealed Self Cooled, Vented Self Cooled,
Forced Cooled
MESSAGE
TOP-OIL RISE OVER
AMBIENT: 35°C
Range: 1 to 200°C in steps of 1
MESSAGE
THERMAL CAPACITY:
100.00 kWh/°C
Range: 0.00 to 200.00 kWh/°C in steps of 0.01
MESSAGE
WINDING THERMAL TIME
CONSTANT: 2.00 min
Range: 0.25 to 15.00 min. in steps of 0.01
P
R
I
n W
( )
2
R ×
=
I
n W
( )