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New generation IZM97, 99 low voltage air circuit breaker instruction manual
MN013010EN February 2020 www.eaton.com.cn
Section 6: Protective characteristic curves
IZM97(99)...V(U)...PXR20/25 Instantaneous(I) Curves
I-Protection: Adjustable
Notes:
1. The Instantaneous settings have conventional 100% ±10% as the pickup points.
2. The nominal Instantaneous trip time is 60ms with auxiliary power supply and 100ms without.
3. Instantaneous protection could be disabled by setting Instantaneous PU switch to OFF position.
4. The curve is shown as a multiple of the Current Rating (I
n
).
5. The end of the curve is determined by the interrupting rating of the circuit breaker.
6. Curves applies from -20°C to +50°C ambient. Temperatures above +85°C will cause over temperature trip.
7. This curve is for 50Hz, 60Hz applications.
8. These curves are comprehensive for series IZM97/99 circuit breakers including all frame sizes, ratings, and constructions.
The total clearing times shown include the response time for trip unit, the breaker opening and the interruption of the current.
.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
100
1
2
3
4
5
6
7
8
9
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
15
12
10
8
7
6
5
4
2
Current in Multiples of Rating (I
n
)
Time in
Sec
o
nds
