43
IZM32 / IN32 low voltage air circuit breaker
MN013017EN May 2022 www.eaton.com
Section 5: Protective characteristic curves
IZM32...V(P)...PXR20/25 Long Delay(L) Curves
L-Protection: I
4
t-Characteristic curve
.01
.02
.03
.04
.05
.06
.07
.08
.09
.1
.2
.3
.4
.5
.6
.7
.8
.9
1
2
3
4
5
6
7
8
9 10
20
30
40
50
60
70
80
90 10
0
1
2
3
4
5
6
7
89
10
20
30
40
50
60
70
80
90
100
200
300
400
500
600
700
800
900
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
.1
.2
.3
.4
.5
.6
.7
.8
.9
Time
in
Se
conds
Current in Multiples of Long Delay Pickup (I
r
)
24
4
15
2
7
0.5
1.5
10
6
0.5
0.1
0.3
0.4
1
3
0.5
Notes:
1. This curve shown as a multiple of the LONG PU setting(I
r
). The actual pickup point occurs at 110% of the I
r
, with ±5% tolerance.
2. SDPU = 1.5x to 10x of I
r
, have 100% ± 10% tolerance.
3. LD Time = 0.5s to 24s, have 100% +0 / -30% tolerance.
4. SD Slope = I²T. The short pickup points have ±10% tolerance.
time setting from 0.1s to 0.5s, with steps of 0.1s, except 0.2s.
tolerance is 100% +0 / -30% except 0. 1s, has tolerance 100% +0 / -40%.
5. I²
r
for top of band with FLAT time minimum value prevailing for bottom of band. For all curves the
response time value projected to I²T line will determine the other break point and shape of the curve.
6. If long delay thermal memory is enabled, trip times may be shorter than indicated in this chart.
The total clearing times shown include the response time for trip unit, the breaker opening and the interruption of the current.
