ABB REF615 L User Manual

It is recommended to use the second harmonic and the waveform
based inrush blocking from the TR2PTDF function if available.
5.1.5 Application
Transformer protections require high stability to avoid tripping during magnetizing
inrush conditions. A typical example of an inrush detector application is doubling
the start value of an overcurrent protection during inrush detection.
The inrush detection function can be used to selectively block overcurrent and earth-
fault function stages when the ratio of second harmonic component over the
fundamental component exceeds the set value.
Other applications of this function include the detection of inrush in lines
connected to a transformer.
A070695 V2 EN
Figure 283: Inrush current in transformer
1YHT530004D05 D Section 5
Protection related functions
615 series 539
Technical Manual

ABB REF615 L Specifications

General

Type	Feeder Protection Relay
Rated Frequency	50/60 Hz
Weight	Approx. 1.5 kg
Communication Protocols	IEC 61850, Modbus RTU, DNP3
Protection Functions	Overcurrent, Earth fault, Thermal overload, Under/Over voltage, Under/Over frequency
Enclosure	IP20