Circuit Breaker

1
Circuit Breaker
1 Bimetal principle
- with current
2 Engine start
4 Other risks
- Overload and risks
- quick switch off
3 Overload
5 Mechanism of short circuit
6 APPLICATIONS
Exit
2
Bimetal principle
 

B72M
Direct heating
Indirect heating
Switch on
Return
3
Current in the bimetal
 

B72M
Direct heating
Indirect heating
Switch off
Return
4
Engine Start
Intensity I
I start
ex 16A
I 10A
Time
Overload
Return
5
Engine Overload
Intensity I
I Over-current over-heating of devices
( Engine, electrical wires etc.)
ex16A
I 10A
Time
Risk???
Return
6
Over current risk
Over current means over-heating of equipment
- Over-heating of electrical wires
- Equipment is destroying
Protection system
Return
7
Protection system
Thermic protection Bimetal part is designed to
be stable with nominal current and to deflect in
case of overload in order to switch off the
circuit.
Bimetal
Return
8
Other risks
Icc Short Circuit
Intensity I
I high overload
I critic
I overload
I start
I normal
Time
Quick switch off
Returr
9
Quick switch off
Icc short circuit
Soft magnetic Core
Intensity I
I high overload
I Critic
I normal
Time
Coil
Return
Protection system
10
Protection system
Magnetic protection In normal use, current is
not high enough to attract the free armature. The
magnetic induction is too low circuit remains
switch off. When a defect appears, current
increases until to reach short circuit current
value. Then there is a strong magnetisation of
the free armature. Thus circuit becomes opened.
Coil at work
Return
11
APPLICATIONS
Circuit breakers
In function of uses - lights - engine -
heating - Domestic and industry Features are
different
Return