Page 74 - SACE Tmax XT - Catalogue

t t
Extremely Inverse
Very Inverse
Standard Inverse
I7
t7
t t
steady
state
start-up
UV
U8
t8
t t
100% 200%
50% 150%
L
U9
OV
S
I I I I V 8
t8 t9
3/40 V I SACE TMAX XT LOW VOLTAGE MOLDED CASE CIRCUIT-BREAKERS
t t
I4 — f12 UF
t4
Ekip Touch/Hi-Touch
t12
t12
f
I
Protection functions
t t
I3 f13 OF
t13
f I
S2 - Second time-delayed overcurrent protection
t
t Extremely Inverse In addition to the Standard S protection, a second (excludible) time-constant protection is available
mean
Very Inverse
Standard Inverse that enables two independent thresholds to be set to ensure precise selectivity, especially under highly
voltage unbalance
I2 U14 crit
8ical conditions.
t2
U1 U2 U3 I I
Phase sequence
V1
t t t t Extremely Inverse This function gives an alarm in case of an inversion of the phase sequence.
Extremely Inverse
I1 Very Inverse
Very Inverse
Standard Inverse senso ciclico
t1
Standard Inverse
U8 8 8
UV
V3 t8 V2
I I I V
UV - Undervoltage (UV - ANSI 27)
t t t
With a constant trip time (t = k), this trips when the phase voltage falls below the set threshold.
U8
U8
UV
U9 UV
OV
t8 t8 t9
t8
V V V
OV - Overvoltage (OV - ANSI 59)
t t t
With a constant trip time (t = k), this trips when the phase voltage exceeds the set threshold.
U9
OV
U9 f12 OV
UF
t8 t9
t12 t8 t9
t12
V V f
t t t t UV2 & OV2 - Second protection against undervoltage and overvoltage (ANSI 27 and 59)
U9 This enables two minimum and maximum voltage thresholds to be set with different delays to discrimi-
OF
f13 nate, for example, between voltage dip transients due to the start-up of a motor and an actual fault.
f12
UF
t9 f12 U16 UF
t12 t16 t13
t12
t12
t12
f f V f
VU - Voltage unbalance (VU – ANSI 47)
t t
mean With a constant trip time (t = k), this protects against an unbalance between the voltages of the single
phases that are protected by the circuit-breaker.
f13
OF
f13 OF
U14 voltage unbalance
t13
t13
U1 U2 U3 f f
S(V) - Voltage controlled overcurrent protection (ANSI 51V)
t V1 1 mean This provide protection from a maximum current with a constant trip time (t = k) that is sensitive to the
mean
voltage value. Following a voltage drop, the current set threshold decreases in steps or linearly. It is
Ks U14 senso ciclico
voltage unbalance
voltage unbalance
U14
t20 possible to set the operating mode to: active, alarm only, or deactivated. The protection operates also
with the circuit-breaker open, thus allowing fault identification before circuit-breaker closing.
V3
U3 I
U2
U1
U2
U1 KsxI20 I20 U3 V2
V1
V1
senso ciclico
senso ciclico
V3
V3 V2
V2