Specifications
800 – 2000A Instantaneous Pickup for Illustrative Purposes
Adjustable Instantaneous Pickup
The Instantaneous Pickup adjustment is used to set the
current level at which the breaker will trip without an inten-
tional time delay. Non-delayed tripping, as a result of a severe
overcurrent condition, minimizes potential damage to electrical
systems and equipment. On trip units for 800, 1200, and
2000A SB breaker sizes, Instantaneous Pickup adjustment
may be set to 1.5, 2, 3, 4, 5, 6, 7, 8, 10, or 12 times I
n
. On trip
units for 3200, 4000, and 5000A frame sizes, Instantaneous
Pickup adjustment may be set to 1.5, 2, 3, 4, 5, 6, 7, 8, 9, or 10
times I
n
.
Instantaneous Pickup
Instantaneous Override
On all trip units, an instantaneous override function has been
provided. It is set nominally at the short time rating of the
respective breaker frame size.This allows the breaker to ride
through high faults up to its short time capability; however, it
is self-protecting above these values.
Discriminator Circuit (Making Current Release)
This circuit overrides the short time delay function should the
breaker attempt to close into a faulted system, tripping the
breaker instantaneously.This discriminatory function is enabled
for the first 6 cycles of current flow, after which normal short
time characteristics operate.
Instantaneous Override (Illustrated with Short Time Fixed Delay)
Operations – Instantaneous Fault Protection
Adjustable Instantaneous Pickup
16
Instantaneous
Pickup
xl
n
12
1.5
2
3
4
5
6
7
8
10
Breaker Frame Size
Short Time kA Rating
(t=0.5 seconds)
1200A 25
2000A 35
3200A 50
5000A 65
Instantaneous
Pickup
xl
n
10
1.5
2
3
4
5
6
7
8
9
Available
Switch
Settings
Continuous
Operating
Current
Long
Time
Delay
Instantaneous
Pickup
0.1
10,000
1, 0 00
100
10
0.01
0.1
1
110100xl
n
Time In Seconds
Continuous
Operating
Current
Long
Time
Delay
Short
Time
Pickup
Short Time
Fixed Delay
Instantaneous
Override
0.1
10,000
1, 0 00
100
10
0.01
0.1
1
110100
xl
n
Time In Seconds
800, 1200, 2000A
Frame Sizes
3200, 4000, 5000A
Frame Sizes
12
1.5
2
3
4
5
6
7
8
10