Three-phase overvoltage protection (PHPTOV) - Arc protection - Merging unit - Transformer protection - 2 winding - Product Guide - RET615 Transformer Protection and Control - Relion 615 series - 5.0 FP1 IEC - IEC - 24.05.2023

RET615 Product Guide

Table 1. Three-phase overvoltage protection (PHPTOV)
Characteristic Value
Operation accuracy Depending on the frequency of the measured voltage: f n ±2 Hz
±1.5% of the set value or ±0.002 × U n
Start time Minimum Typical Maximum
U Fault = 1.1 × set Start value

23 ms

27 ms

31 ms

Reset time Typically 40 ms
Reset ratio Depends on the set Relative hysteresis
Retardation time <35 ms
Operate time accuracy in definite time mode ±1.0% of the set value or ±20 ms
Operate time accuracy in inverse time mode ±5.0% of the theoretical value or ±20 ms
Suppression of harmonics DFT: -50 dB at f = n × f n, where n = 2, 3, 4, 5,…
1 Start value = 1.0 × U n, Voltage before fault = 0.9 × U n, f n = 50 Hz, overvoltage in one phase-to-phase with nominal frequency injected from random phase angle, results based on statistical distribution of 1000 measurements
2 Includes the delay of the signal output contact
3 Maximum Start value = 1.20 × U n, Start value multiples in range of 1.10...2.00