Three-Phase Thermal Protection For Feeders, Cables And Distribution Transformers T1Pttr - ABB RELION Series Technical Manual

Section 4
Protection functions
4.1.3
4.1.3.1
4.1.3.2
4.1.3.3
252
Table 267: (F)DPHLPDOC Technical revision history
Technical revision
B
C
D
E
Three-phase thermal protection for feeders, cables and
distribution transformers T1PTTR
Identification
Function description
Three-phase thermal protection for
feeders, cables and distribution
transformers
Function block
A070691 V3 EN
Figure 135: Function block
Functionality
The increased utilization of power systems closer to the thermal limits has generated
a need for a thermal overload function for power lines as well.
A thermal overload is in some cases not detected by other protection functions, and the
introduction of the three-phase thermal protection for feeders, cables and distribution
transformers function T1PTTR allows the protected circuit to operate closer to the
thermal limits.
An alarm level gives an early warning to allow operators to take action before the line
trips. The early warning is based on the three-phase current measuring function using
a thermal model with first order thermal loss with the settable time constant. If the
Change
Added a new input NON_DIR
Step value changed from 0.05 to 0.01 for the
multiplier setting.
Monitored data VMEM_USED indicating voltage
memory use.
Internal improvement.
IEC 61850 IEC 60617
identification identification
T1PTTR 3lth>
1MRS758755 A
Time
ANSI/IEEE C37.2
device number
49F
REC615 and RER615
Technical Manual