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The types of circuit breakers



 it is a device a manual or automatic control, one of whose role is to protect the system against overload and short circuit.
it is composed:
* Several contacts has great breaking capacity.
* Of a thermal trip.
* D electromagnetic release (coil a plunger or armature).
 its operation is simple; the automatic opening of its contact has large switching capacity is realized:
* By action of the thermal release in the event of overload.
* By the action of electromagnetic trip in case of short circuit.

-c is a valid protection for all control and power circuit but the major drawback is its cost is high.

isolate a circuit.
Ensure it fit thermal and magnetic protection and differential of a circuit or a receiver by adding the trigger and ablir or break a circuit

CHARACTERISTICS OF THE NETWORK:
VOLTAGE:
The nominal voltage of the circuit breaker must be at least equal to the voltage between phases
network.
PERMANENT CURRENT:
I'intensité is the current in amperes flowing through the network on which the circuit breaker
is installed. The circuit breaker rating must exceed the continuous current
but lower than the current allowable by the same network.
The continuous current is determined for an ambient temperature of 20 "C.
THE CURRENT:
This is the maximum current in amps that can support the network constantly
according to certain criteria pose. (Tables Fig. 6 and Z § 6.1.6.).
 SHORT CIRCUIT CURRENT:
(Switching capacity)
The circuit breaker breaking capacity must be at least equal to the current three-phase short-circuit may occur point of contact where it is installed.
If the prospective short circuit current is limited by a protective device located upstream breaker breaking capacity can be reduced in a
report (Offspring between breakers § 20.20.)
FREQUENCY:
The normal operating frequency of the circuit breakers are between 50
and 60 Hz.
NUMBER OF POLES:
It depends on the earthing system and the desired function (protection, control, type
receivers, isolation ...).
OUTLINES LINKS:
To rail reRRe Plan IT, TN or lT
(Chapter a.)

 TYPES PROTECNON assignable TO BREAKERS:

 PROTECTION AGAINST INDIRECT CONTACTS:
In TT system is secured by a residual current device (RCD).
In TN regime and Li is assured by protective devices against short circuits; the current setting of these devices determines the maximum length of
following their section cables (NFC 15-100).
SHORT CIRCUIT PROTECTION:
The magnetic trip setting determines the maximum cable length
protection of their section (NFC 16-100).
In case of short circuit, the circuit breaker must pass an energy below
one that can support the cable.
PROTECTION ON CHARGES:
It depends on the type of receiver (motor, transformer ...)
The setting of the thermal release or SSR IDMT integrated in
breaker, provides such protection.


different type of circuit breaker symbol:

Q1: bipolar GFCI.
Q2: PN RCD.
Q7: pole RCD.
Q8: pole RCD.
Q9: disj sect bipolar differential.
Q10: PN disj sect.
Q11: disj sect pole differential.
Q12: single pole breaker.
Q13 pole RCD.
Q14: pole RCD.
Q15: disj sect pole differential.
Q16: disj bipolar sect.
Q17: disj unipolar sect.
Q18 bipolar GFCI.
Q19: disj sect bipolar differential.
Q20: pole breaker.
Q21: disj bipolar sect.
Q22: GFCI pole

Type of circuit breaker:
According to different criteria, there are different types of circuit breaker.
According to their media arcing circuit breaker can be divided:
oil circuit breaker.
Air circuit breaker.
SF6 circuit breaker.
vacuum circuit breaker.

According to their services breaker can be divided:
outdoor Circuit breaker
inner breaker.

According to the circuit breaker operating mechanism they can be divided:
Spring operated circuit breaker.
pneumatic breaker.
hydraulic breaker.

Depending on the level of voltage breaker facility types are designated:

High voltage circuit breaker.
Medium voltage circuit breaker.
Low voltage circuit breaker.

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