Signals; Settings - ABB RELION REX640 Technical Manual

1MRS759142 C
4.1.5.7
4.1.5.8
Table 411: T2PTTR Group settings (Basic)
Parameter Values (Range)
Env temperature Set
Temperature rise
Max temperature
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REX640
Technical Manual
Single time constant
(min)
50
55
60
65
70
75
The default Max temperature setting is 105°C. This value is chosen since even though
the IEC 60076-7 standard recommends 98°C as the maximum allowable temperature
in long-time loading, the standard also states that a transformer can withstand the
emergency loading for weeks or even months, which may produce the winding
temperature of 140°C. Therefore, 105°C is a safe maximum temperature value for a
transformer if the Max temperature setting value is not given by the transformer
manufacturer.

Signals

Table 409: T2PTTR Input signals
Name
I3P
BLOCK
AMB_TEMP
Table 410: T2PTTR Output signals
Name
OPERATE
START
ALARM
BLK_CLOSE

Settings

Unit
-50...100 °C
0.0...200.0 °C
22.0...200.0 °C
Short time constant (min) Long time constant (min) Weighting factor p
5.1 82
5.6 90
6.1 98
6.7 107
7.2 115
7.8 124
Type Default Description
SIGNAL - Three-phase currents
BOOLEAN 0=False Block signal for activating the blocking mode
FLOAT32 0 The ambient temperature used in the calculation
Type Description
BOOLEAN Operate
BOOLEAN Start
BOOLEAN Thermal Alarm
BOOLEAN Thermal overload indicator. To inhibite reclose.
Step Default
1 40
0.1 78.0
0.1 105.0
Section 4
Protection functions
0.4
0.4
0.4
0.4
0.4
0.4
Description
Ambient temperature used when no
external temperature measurement
available
End temperature rise above ambient
Maximum temperature allowed for the
transformer
373