GB 24350-2009Selective circuit breakers for overcurrent protection for household and similar installation (English PDF)

3.1 Electric

3.1.1

For making and breaking one or more electrical circuits in current devices.

3.1.2

With separable contacts to open or close one or more electrical circuit switching equipment.

3.1.3

When the current exceeds a given value for a sufficient time to melt through one or more specially designed and proportionate melt off their access circuit and breaking current switching equipment.

3.1.4

Can turn, carrying and breaking currents under normal circuit conditions and under specified abnormal circuit conditions such as short circuit current, but also to take Pass, carrying a certain time and breaking current automatic mechanical switching equipment.

3.1.5

One kind of current-limiting circuit breaker. Can turn, carrying and breaking current in the circuit. In particular, it should be able to take place in the lower loop over separation Under the current circumstances, if the lower-level overcurrent protection device can cut off the current, limiting itself only and does not cut off the overcurrent. Meanwhile, in the present Under the conditions specified in the standard, it should be able to meet on the lower level overcurrent protection device selective protection requirements.

3.1.6

3.2 General terms

3.2.1

Any current exceeding the rated current.

3.2.2

Current generator electrically lossless circuit too.

Note. If the overload current for a long enough period of time may also cause damage.

3.2.3

During normal operation, the impedance between the potential of different parts of negligible faults resulting overcurrent.

Note. The short-circuit current may be caused by a fault may also be caused by an incorrect connection.

3.2.4

Including all conductive parts SMCB in its closed and open circuit inside.

Note. completely or partially connected in parallel with the main circuit to circuit called a sub-circuit can also be seen as the main circuit.

3.2.5

SMCB for closing or opening operation or operations for both circuits (except the main current path of the circuit).

NOTE. The control circuit of the power supply is connected through power grid applied.

3.2.6

All conductive parts in addition to the main circuits and control circuits outside the SMCB included in the SMCB.

3.2.7

SMCB components only with a separate conductive paths connected to the main circuit, the main circuit itself has a touch for connecting and disconnecting head. It does not include those for the respective poles of each pole together and operate together parts.

3.2.7.1

Over-current release (see 3.3.6) pole.

3.2.7.2

No over-current release (see 3.3.6) of the pole, but in other respects the same SMCB usually very protective with the same performance.

Note 1. To ensure compliance with the technical requirements of the unprotected pole may protect the gate structure identical or special structure.

Note 2. If the unprotected pole short-circuit capacity and protection very different, marked by the manufacturer.

3.2.7.3

Only for opening and closing the neutral line need to have an extremely short-circuit capacity.

Note. When SMCB off, opening and closing to allow neutral pole remains closed.

3.2.8

SMCB ensure the continuity of the main circuit a predetermined position.

3.2.9

There predetermined position clearances between the main circuit to ensure SMCB break contact.

3.2.10

3.2.10.1

Under specified conditions determined SMCB surrounding air temperature (for enclosed SMCB, refers to the air temperature outside the enclosure).

3.2.10.2

As the time - overcurrent characteristic reference ambient air temperature.

3.2.11

Movable contacts conversion or reverse conversion from the open position to the closed position.

NOTE. If the operation should be distinguished is the electrical sense (ie, making and breaking) referred to the opening and closing operation, and the operation in the mechanical sense (ie closing and opening) said Mechanical operation.

3.2.12

Conversion from one position to another and then back to the starting position of continuous operation.

3.2.13

Continuous operation with a predetermined time interval specified.

3.2.14

SMCB main contact in the closed position, through a long period of uninterrupted work at a steady current system (power-on time can be a few stars Period, months or even years).

3.2.15

Each test SMCB in the manufacture and/or after manufacture conducted to determine if it meets certain criteria.

3.3 Structural components

3.3.1

SMCB main circuit contacts in the closed position to carry the current of the main circuit.

3.3.2

Arcing contacts formed thereon.

Note. The primary contact arcing contact and can be designed the arcing contacts into a single contact, it contacts other than after the first opening and closing, in order to protect other Contacts from damage.

3.3.3

SMCB connected to the control circuit by SMCB contacts mechanically operated.

3.3.4

Connected to the auxiliary circuit and mechanically operated by SMCB contacts (for example, used to indicate the position of the contacts).

3.3.5

And on SMCB mechanical connection (or the composition of the whole), to release the retaining mechanism and SMCB automatic disconnection device.

3.3.6

When the release of the current exceeds a predetermined value, so that there is a delay or no delay SMCB disconnect the trip.

Note. In some cases, this value may be related to the rate of current rise.

3.3.7

And over-current delay value is inversely proportional to the operation after overcurrent release.

NOTE. This release may be designed to over-current is large, approaching a minimum of delay determined.

3.3.8

SMCB directly from the main circuit current excitation of overcurrent release.

3.3.9

Used as overload protection overcurrent release.

3.3.10

It can be conductive, but not necessarily used to carry the operating current member.

3.3.11

Under normal circumstances do not live, but may become live under fault conditions is easily accessible conductive parts.

NOTE. Typical exposed conductive member is a metal wall of the housing and metal parts and other operations.

3.3.12

Terminals are SMCB conductive member may be re-used with an external circuit electrical connections.

3.3.13

Wiring for connecting a wire and subsequent disconnection of these wires, or for two or a few detachably interconnecting wires Terminal, which is connected directly or indirectly with a variety of screws or nuts to complete.

3.3.14

Wire into a hole or cavity, by the end of the screw to compress screw-type terminal lead, which can be used directly by the screw fastening pressure Nail ends or applied through a transition element of pressure applied by the end of the screw.

NOTE. The sample pillar terminals are shown in Figure F. 1.

3.3.15

Wire fastening screw head below the screw-type terminal. The clamping pressure may be applied directly or through a transition to zero by the head of the screw Member, such as. gaskets, plywood or a locking device is applied.

NOTE. Screw terminals example shown in Figure F. 2.

3.3.16

The conductor is clamped under a nut screw-type terminal. The clamping pressure can be directly from a suitably shaped nut or through an applied Transition parts, such as. gaskets, plywood or a locking device is applied.

Note. Examples of stud terminals are shown in Figure F. 2.

3.3.17

Wire fastening screw-type terminal in the saddle plate by two or more screws or nuts.

NOTE. saddle terminals example shown in Figure F. 3.

3.3.18

Using a screw or nut fastening screw terminals or screw terminals cable lug or bus.

NOTE. The sample lug type terminals is shown in Figure F. 4.

3.3.19

Wiring for connecting a wire and subsequent disconnection of these wires, or for two or a few detachably interconnecting wires Terminals. Which is connected directly or indirectly to complete by means of springs, wedges, eccentrics or cone wheel, etc., in addition to strip the insulation, the need for lead Line for special processing.

3.3.20

3.3.21

Screwed deformation resistance with high deformation resistance material than the material of low screw hole screws.

Tapered screw threads, bore their ends threaded conical shape.

Threaded by the screw action generated to reliably formed only after the screw is rotated a sufficient number of turns beyond the threaded portion of the cone.

3.3.22

Tapping screw having a continuous thread, the thread does not function from the hole cutting material.

NOTE. Thread tapping screw extrusion molding example is shown in Figure 1.

3.3.23

Tapping screw having a discontinuous thread, which has a threaded hole from cutting the material functions.

Note. The thread cutting self-tapping screws example shown in Figure 2.

3.4 Operating Conditions

3.4.1

SMCB conversion from the open position to the closed position of the operation.

3.4.2

SMCB from the closed position to the open position of the operation.

3.4.3

Entirely by human action is directly applied, so that the speed and force of the operation depends on the action of the operator.

3.4.4

Energy derived from human, and storage and release of stored energy operating in a continuous operation, and thus the operation speed and force of the operator's move as irrelevant.

3.4.5

After the closing operation starts, if the automatic opening operation, even if the instruction remains closed, its movable contact can return to and remain in the open position the SMCB.

NOTE. To ensure the normal breaking the current may have been generated, you may need to make the contacts momentarily reach the closed position.

3.5 Characteristic value

Unless otherwise specified, all current and voltage are RMS.

3.5.1

Used to determine the value of any one characteristic of a predetermined amount of SMCB design and manufacture of working conditions.

3.5.2

SMCB)

If the impedance of each pole with a negligible wire SMCB instead, the current flowing in the circuit.

Note. The current can also be expected as an actual current, for example. prospective breaking current, prospective peak current.

3.5.3

After switching on the expected peak transient current.

Note. This definition assumes that the current is ideal SMCB turned on, that is, its zero impedance instantaneously change from the infinite, current can flow through several different paths Circuits, such as multi-phase circuit, this definition further assumes that the current is turned on simultaneously in all poles, even considering only the current one pole.

3.5.4

Current switched occur that may lead to the moment of the maximum prospective peak current when.

Note. For multi-phase multi-pole circuit SMCB, refers only to the maximum expected peak current unipolar.

3.5.5

Under specified conditions, with SMCB to access, load and breaking their off-time AC component of the prospective current with an effective value of.

3.5.5.1

Under the test procedure, which does not include the specified conditions SMCB carrying the appointed time at rated current breaking capacity.

3.5.5.2

Under the test program, which prescribed conditions include SMCB carrying the appointed time at rated current breaking capacity.

3.5.6

In the process of breaking arc is generated at the moment a very SMCB current flowing.

3.5.7

Just before turning current is applied between the terminals SMCB a pole voltage.

Note. This definition refers to the monopole SMCB. Multi-polar SMCB, the applied voltage is the voltage between the power supply terminal SMCB.

3.5.8

After breaking current between terminals SMCB pole voltage appearing.

Note 1. This voltage may think there are two successive time intervals, the first one appeared transient voltage interval, followed by a second time interval only appear Power frequency recovery voltage.

Note 2. This definition refers to the monopole SMCB. Multi-polar SMCB, recovery voltage is the voltage between the power supply terminal SMCB.

3.5.8.1

During the time a significant feature of the transient recovery voltage.

Note. Depending on the characteristics of the circuit and SMCB transient voltage may be oscillatory or non-oscillation of both. This includes a multi-phase circuit voltage neutral point shift Voltage.