System information
™
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Masterpact™ NT and NW Universal Power Circuit Breakers
Trip Curves
174
05/2014
Micrologic 3.0 Trip Units
Figure 170: Micrologic 3.0A Trip Unit: Long-Time Pickup and Delay
1.5
1
1
CURRENT IN MULTIPLES OF Ir (Ir = LONG-TIME SETTING x In)
CURRENT IN MULTIPLES OF Ir
(Ir = LONG-TIME SETTING x In)
.5
.6
.7
.8
.9
1.5
2
3
4
5
6
7
8
9
10
15
20
30
40
50
60
70
80
90
100
.5
.6
.7
.8
.9
2
3
4
5
6
7
8
9
10
15
20
30
40
50
60
70
80
90
100
200
300
400
500
600
700
800
900
1000
1500
2000
3000
4000
6000
7000
8000
9000
5000
10000
.005
.006
.007
.008
.009
.01
.015
.02
.03
.04
.05
.06
.07
.08
.09
.1
.005
.006
.007
.008
.009
.01
.015
.02
.03
.04
.05
.06
.07
.08
.09
.1
.15
.2
.3
.4
.5
.6
.7
.8
.9
1
.15
.2
.3
.4
.5
.6
.7
.8
.9
1
1.5
2
3
4
5
6
7
8
9
10
1.5
2
3
4
5
6
7
8
9
10
15
20
30
40
50
60
70
80
90
100
15
20
30
40
50
60
70
80
90
100
150
200
300
400
500
600
700
800
900
1000
1500
2000
3000
4000
5000
6000
7000
8000
9000
10000
TIME IN SECONDS
CYCLE
2
1
1 CYCLE
150
24
20
12
.5
8
4
2
1
16
24
16
LONG-TIME PICKUP
x In = Ir
LONG-TIME DELAY
SECONDS AT 6 x Ir
Curve No. 0613TC0006
Drawing No. B48095-613-06
Micrologic 3.0A Trip Unit
Characteristic Trip Curve No. 613-6
Long-Time Pickup and Delay
The time-current curve information is to be used for
application and coordination purposes only.
Curves apply from -30°C to +60°C (-22°F to +140°F)
ambient temperature.
NOTE:
1. There is a thermal-imaging effect that can act to
shorten the long-time delay. The thermal-imaging
effect comes into play if a current above the long-time
delay pickup value exists for a time and then is cleared
by the tripping of a downstream device or the circuit
breaker itself. A subsequent overload will cause the
circuit breaker to trip in a shorter time than normal. The
amount of time delay reduction is inverse to the
amount of time that has elapsed since the previous
overload. Approximately twenty minutes is required
between overloads to completely reset thermal-
imaging.
2. The end of the curve is determined by the
instantaneous setting of the circuit breaker.
3. Total clearing times shown include the response times
of the trip unit, the circuit breaker opening, and the
extinction of current.
4. See trip curve 613-8 for instantaneous pickup trip
curve.