Download AVOP-ELEKTRO-SKA-011

Tutorial: Mechanic - electrician
Topic:
Basics of electrical engineering
the 2nd. year
Three-phase current
Circuit breaker
Prepared by: Škarka Miloš
Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002
je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.
The circuit breaker is an electric device, which
during the excessive current (so called over
current) (usually during overload or short-circuit)
automatically disconnects electric circuit and by
that protects operating personnel against possible
injury caused by an electric current and protected
electric device against damage.
Circuit breaker provides in electric circuit
these basic functions:




Safe automatic disconnection of the circuit
in case of short-circuit
Safe automatic disconnection of the circuit
in case of overcurrent
Manual disconnection of the circuit
Manual connection of the circuit
Circuit breaker characteristic values are:
•Nominal voltage, which it is designed for
•Nominal current, which is permanently transmitted
without circuit disconnection
•Short-circuit current, which is able to turn off (on
ordinary home appliances typically 6 to 25
kiloampers).
•Disconnection characteristic determines the
dependence of the disconnection time on the
amount of overcurrent or short-circuit current.
1.
2.
3.
4.
5.
Control lever
Locking mechanism
Contacts
Supply bolt terminal
Bimetal component for overload
facilities
6. Regulation component for
sensitivity setting (usually not
on ordinary home circuit
breakers)
7. Electromagnetic trigger for
short-circuit facilities
8. Quenching chamber
One-pole circuit breaker
Three-pole circuit breaker
Connection of the pad and circuit breakers using connection battens
0,2 A
- 1,6 black
A
16 A
grey
20 A
blue
2A
pink
25 A
yellow
4A
brown
32 A
purple
6A
green
40 A
black
8A
Light green
50 A
white
10 A
red
63 A
copper
13 A
sand
Usage: for electric circuits protection
B – with devices not causing current impacts
(protection of lines)
C – with devices causing current impacts (bulb
groups, lines with motors)
D – with devices causing high current impacts
(transformers, two-pole motors)
Picture 1
• Main components of
the current breaker in
picture 1
• Current breaker main
functions
• Main parameters of
current breakers
• Current breaker
characteristics
http://www.bonega.cz
http://www.google.cz
http://cs.wikipedia.org