Compact® NSF and NSJ 150 to 600 A Circuit Breakers

Section 4—Trip Units

Indications

Load indication (LED) in front (6):

Lights solid at 90% of Ir threshold

Flashes at >105% or greater of Ir threshold

Test

Test connector in front (7) for connection to test kit to check circuit breaker operation after fitting the trip

 

unit or other accessories.

Setting Example

Question: What is the overload protection threshold of a Compact NSJ400 circuit breaker equipped

 

with trip unit STR23SP where Io = 0.5 and Ir = 0.8?

Answer: In x Io x Ir = 400 x 0.5 x 0.8 = 160 A

The same trip unit with the same settings, mounted on an NSJ600 circuit breaker will have the following tripping threshold: In x Io x Ir = 600 x 0.5 x 0.8 = 240 A.

06153066

Io

.9

 

 

Ir

.8

 

.9

.93

 

 

 

.7

1

.88

 

.95

 

.63

 

.85

 

.98

 

.5

 

.8

 

1

 

x In

 

 

x Io

 

400 x 0.5 x 0.8 = 160 A

 

 

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Schneider Electric Class 615 dimensions Indications, Test, Unit or other accessories, Setting Example