35
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) and Short Delay(S) Curves
S-Protection with: I²t-Characteristic curve ON
.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
24
4
15
2
7
0.5
1.5
10
6
0.5
0.1
0.3
0.4
1
3
0.5
Time
in
Se
conds
Current in Multiples of Long Delay Pickup (Ir)
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
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.
