Setting Example - ABB REG670 Applications Manual

1MRK 502 071-UEN -
17.10.3
17.10.3.1
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual
Table 71: Suggested maximum temperature limits
Type of Normal life
temperature expectancy loading
Insulated winding 120
hot spot
temperature in °C
Top oil 105
temperature in °C
IEEE standard has also suggested the limits of temperature and load for loads higher
than transformer nameplate.
• For distribution transformers with 65°C hot spot temperature rise:
• Top oil temperature = 120°C
• Hot spot winding temperature = 200°C
• Short-time loading (1/2 h or less) = 300%
• For power transformer with 65°C hot spot temperature rise:
• Top oil temperature = 110°C
• Hot spot winding temperature = 180°C
• Maximum loading = 200%
Settings related to warning and alarm are:
WrnHPTmpLev1: This setting is used to set the level 1 value for hot spot temperature
warning.
WrnHPTmpLev2: This setting is used to set the level 2 value for hot spot temperature
warning. This should be more than the WrnHPTmpLev1 setting.
tDelayToAlarm1: This setting is used to set the time delay for the level 1 hot spot
temperature alarm. This time setting can be less than the winding time constant. For
example if the winding time constant is 420 sec, this setting can be 400 sec.
tDelayToAlarm2: This setting is used to set the time delay for the level 2 hot spot
temperature alarm. This should be less than time setting in tDelayToAlarm1.

Setting example

Transformer Rated Data
Table 72: Transformer Rated Data
Parameter
Frequency
Rated Power
Voltage ratio
Table continues on next page
Planned loading Long term loading
beyond nameplate
rating
130 140
110 110
Value
50 Hz
500 MVA / 500 MVA / 20 MVA
415 kV / 230 kV / 20 kV
Section 17
Monitoring
Short term loading
180
110
Note
665