sepam 20 user manual - Schneider Electric

3
Protection functions Phase-to-phase overvoltage
ANSI code 59
3/28
MT10876
Operation
This protection is three-phase:
b it picks up when one of the phase-to-phase voltages concerned is greater than
the Us set point
b the protection includes a definite time delay.
Block diagram
U21
U32
U13
Characteristics
Us set point
U > Us
Setting 50 % Unp to 150 % Unp (2)
Accuracy (1) ±2 % or 0.005 Unp
Resolution 1 %
Drop-out/pick-up ratio
Time delay T
97 % ±1 %
Setting 50 ms to 300 s
Accuracy (1) ±2 %, or ±25 ms
Resolution
Characteristic times
10 ms or 1 digit
Operation time pick-up < 35 ms (typically 25 ms)
Overshoot time < 35 ms
Reset time
(1) In reference conditions (IEC 60255-6).
(2) 135 % Unp with TP 230 V / 3.
< 40 ms
T
0
time-delayed output
“pick-up” signal
PCRED301005EN - 06/2008