EP1685578B1 - Circuit breaker comprising a fuse - Google Patents

Abstract

An aim is to make wiring accessories in distribution boards more compact. The aim is achieved by integrating fuses in switching protective devices that are used for functional switching, interrupting, and overload protection such that switching protective devices including fuses can be produced in a housing while short-circuit protection can be coupled to the interruption function if necessary by isolating one fuse from the contact/s.

Description

The present invention relates to a contactor with an operating switching device for switching on and off of a device to be controlled, a disconnecting device for disconnecting an input terminal of an output terminal, which is connectable to the device to be controlled, and a protective device for protecting the device to be controlled against short circuit.

Electronic switching devices, which often have silicon thyristors as switching elements, can be subdivided into two types of devices: solid-state contactors and soft starters. Soft starters are mainly used to start motors and control or regulate the voltage during startup by means of phase control. Semiconductor contactors only switch on and off. Semiconductor contactors are often used to switch ohmic loads, mainly electric heaters. For this purpose, the so-called vibration packet control for temperature control or - control is often used.

Silicon thyristors can not actively switch off a short circuit. Therefore, either circuit breakers or fuses must be connected upstream. In this case, the short-circuit protection can be performed by assignment type 1 or 2. According to assignment type 1, the switching device is destroyed in the event of a short circuit and must be completely replaced. After assignment type 2, the switchgear remains fully functional after a short circuit. The switching device remains intact. With today's prospective short-circuit currents (> 30 kA), the assignment type 2 can only be realized with special semiconductor protection fuses. The short-circuit protection and the disconnector function are commonly implemented in a unit upstream or downstream of the electronic switching device. For this Either circuit-breakers or fuse-disconnectors with fuses are suitable.

From low-voltage networks, the power is usually decoupled via so-called "branches". Each branch should have the functions of load switching, overload switching, disconnection, short-circuit protection and overload protection. These functions are typically handled by multiple standalone devices. As an exception Télémecanique a device is known which is electromechanically switched and has the functions of disconnection, short-circuit, overload protection and operational switching. Otherwise, this variety of functions is realized by at least two devices.

In the case of a fused branch with an electronic switching device without overload protection, an overload relay must still be added to the circuit arrangement. In the case of a feeder with circuit breaker according to assignment type 2, additional semiconductor fuses must be provided. In both cases a total of three devices are connected in series. Especially for branches with assignment type 2, i. where fuses must be used, so relatively large space is required. Since the fuse holder or fuse load disconnector are usually not tuned to the width of the electronic switchgear, results in the cabinet no efficient space utilization. This results in high costs for the control cabinet and the room in which the control cabinet is installed.

EP0067914A discloses a fuse unit for home installation. With this fuse unit it is possible to change a fuse without tools.

The object of the present invention is thus to propose more compact switching devices for switching and protecting electrical loads.

According to the invention, this object is achieved by a switching protection device with an operating switching device according to claim 1, ie a switching device for operational switching on and off of a consumer to be controlled, a separator for Disconnecting an input terminal from an output terminal connectable to the device to be controlled, and a protection device for short-circuit protection, the protection device comprising at least one short-circuit cut-off fuse, and wherein the operation switching device, disconnecting device, and protection device are connected in series per phase and are integrated in a housing.

• Eine optimale Platzausnutzung wird ermöglicht.
• Alle Komponenten können aufeinander abgestimmt werden.
• Es kann eine Einsparung von Verdrahtungsaufwand erzielt werden.
• Der logistische Aufwand wird erheblich reduziert, da nur ein Gerät beschafft und gelagert werden muss. Ohne die erfindungsgemäße Integration müssten für die gleiche Funktionalität Sicherungslasttrenner, Sicherungen und ein elektronisches Schaltgerät einzeln gehandhabt werden.

The integration of the at least one fuse and the separator with isolator properties into a switchgear results in the following advantages:

• Optimum space utilization is made possible.
• All components can be coordinated with each other.
• It can be achieved a saving of wiring effort.
• The logistical effort is considerably reduced since only one device has to be procured and stored. Without the integration according to the invention, fuse load disconnectors, fuses and an electronic switching device would have to be handled individually for the same functionality.

The switching protection device according to the invention is designed as a soft starter, also called semiconductor motor control unit, or semiconductor contactor.

Preferably, the at least one fuse can be removed from the housing from the outside, for example, for replacement. The at least one fuse includes a semiconductor fuse or semiconductor protection fuse. Thus, with regard to a short circuit, the assignment type 2 can be met with electronic switching points.

Advantageously, the protective device is arranged between the separating device and an output terminal to the device to be controlled. Thus it is possible that when opened Separation point a voltage-free fuse change from au-βen can be done.

The separator is combined with the fuse, separating and releasing the fuse for removal of at least one contact when open. The fuse is arranged in a movable part of the separator. For the movable part of the separator, a rotating or sliding mechanism can be provided.

Preferably, the separator has two separation points. Furthermore, the separator may have the functionality of a fuse load disconnector.

Preferably, the fuses are designed as cylindrical fuses.

In addition, a monitoring device for registering a triggering of the at least one fuse may be provided. This can be used to report the release of the backup and process it further.

To reduce power dissipation, electronic switches can be bridged with mechanical contacts (e.g., relays or contactors).

Furthermore, an overload device, in particular with a thermal overload relay, e.g. integrated with bimetallic strip or with electronic overload relay. In this case current transformers can be used for current measurement. With the current signal, the overload protection can then be realized.

The switching protection device according to the invention or the entire branch circuit can be integrated into a construction and wiring system, with an exchange of the complete Device is possible by plug-in technology. This reduces the effort required to change a device to a minimum. However, the device should only be pluggable in the OFF position. This can be done for example by a mechanical locking of the fuse load disconnector with the "basic carrier", ie the device can only be replaced with an open fuse load disconnector.

The branch can be 1 or 3-pole. For 3-pole devices, only two current paths can be switched, i. be provided with switching elements.

FIG 1

ein Schaltbild eines "geschlossenen" Verbraucherabzweigs mit elektronischer Schaltstelle ohne Überlastschutz;

FIG 2

ein Schaltbild eines "offenen" Verbraucherabzweigs mit elektronischer Schaltstelle ohne Oberlastschutz und mit einer Trennstelle;

FIG 3

ein Schaltbild eines "offenen" Verbraucherabzweigs mit elektronischer Schaltstelle mit Überlastschutz und mit zwei Trennstellen;

FIG 4

ein Schaltbild eines "offenen" Verbraucherabzweigs mit mechanischer Schaltstelle mit Überlastschutz und mit einer Trennstelle; und

FIG 5

eine perspektivische Ansicht eines erfindungsgemä-βen Schaltschutzgeräts.

The invention will now be explained in more detail with reference to the accompanying drawings, in which:

FIG. 1

a circuit diagram of a "closed" load feeder with electronic switch without overload protection;

FIG. 2

a circuit diagram of an "open" load feeder with electronic switching point without upper load protection and with a separation point;

FIG. 3

a circuit diagram of an "open" load feeder with electronic switching point with overload protection and with two separation points;

FIG. 4

a circuit diagram of an "open" load feeder with mechanical switching point with overload protection and with a separation point; and

FIG. 5

a perspective view of a device according to the invention β-switchgear.

The embodiments explained in more detail below represent preferred embodiments of the present invention.

This in FIG. 1 reproduced inventive switchgear 1 is used to switch a 1- or 3-pole line. For a 3-pole cable is accordingly a 3-pole device consisting of three current paths to form.

The switching protection device 1 has simplified an electrical switching device 2 and connected in series with a fuse 3. In the circuit shown on the left side of FIG. 1 the fuse is reproduced in the closed circuit. In FIG. 2 the fuse 3 is shown in the open position. In this position, the circuit, not shown, is interrupted by a voltage network to a consumer. If the required clearances and creepage distances are complied with by this separation, it can be said that there is a standardized separation characteristic. If both terminals of the fuse are disconnected from the circuit, there is a double separation point. This makes it possible in any case to replace the fuse 3 without voltage.

In FIG. 3 is a further alternative of a erfindungsgemä-βen, compact switching protection device reproduced. In the illustration, fuse 3 is disconnected from the current path at two separation points. Thus, the fuse 3 can be removed from the contactor 1 voltage-free. After the switching device 2, which is also reproduced here as a thyristor, an overload device for protection against overload is arranged in the switching protection device 1.

An illustrative example of a shunt protection device is shown in FIG FIG. 4 shown. Compared to the embodiment of FIG. 3 Here is only one separation point provided on the fuse 3. Thus, the fuse 3 when removing, ie when the load feeder is open, may be in a non-voltage-free state. In the embodiment of FIG. 4 is the electronic switching device 2 of FIG. 3 replaced by a mechanical switch. This makes it clear that the individual in connection with the FIGS. 1 to 4 shown Components in the switchgear devices can be combined in any way.

FIG. 5 shows a switchgear 1 in perspective view. It has input terminals 4 and output terminals 5. The fuse 3 is housed in a movable part 6 of the disconnecting device. Via a handle 7, the movable part 6 can be given according to the arrow to the outside. In this tilting movement, the fuse 3 is released from the contacts (not shown) on both sides and can be removed without tension. This ensures the function of a fuse switch disconnector.

The switching protection devices according to the invention can be used both in installation technology and in industrial technology.

Claims (12)

1. Protective switching device, which is in the form of a semiconductor motor controller or a semiconductor contactor, having

   - an electrical switching device (2) for switching a load on and off during operation,

   - a disconnection device for disconnection of an input terminal from an output terminal which can be connected to the appliance to be driven, and

   - a protective device for protection of the appliance to be driven against short circuits,

   the protective device having a fuse (3) in each phase for disconnection in the event of a short circuit, with the electrical switching device, the disconnection device and the protective device being connected in series and being integrated in a housing, with the disconnection device, when in the open state, blowing and releasing the at least one fuse (3) for removal of at least one contact, for removal, the at least one fuse (3) being arranged in a moving part (6) of the disconnection device, the at least one fuse (3) being in the form of a semiconductor protective fuse.
2. Protective switching device according to Claim 1, in which the at least one fuse (3) can be removed from the housing.
3. Protective switching device according to one of the preceding claims, in which the protective device is arranged between the disconnection device and an output terminal to the appliance to be driven.
4. Protective switching device according to one of the preceding claims, in which the disconnection device can be opened and closed by means of a rotary or slide mechanism.
5. Protective switching device according to one of the preceding claims, in which the at least one fuse (3) is in the form of a cylindrical fuse.
6. Protective switching device according to one of the preceding claims, in which the disconnection device has the functionality of a fused load disconnector.
7. Protective switching device according to one of the preceding claims, in which the disconnection device has two disconnection points.
8. Protective switching device according to one of the preceding claims, which has a monitoring device for recording of tripping of the at least one fuse (3).
9. Protective switching device according to one of the preceding claims, in which electronic switching points can be bridged by mechanical contacts.
10. Protective switching device according to one of the preceding claims, which has an overload device.
11. Protective switching apparatus according to Claim 10, in which the overload device has an overload relay.
12. Protective switching device having three current paths according to one of the preceding claims for three-pole appliances, in which one of the current paths has no operating switching device.

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