DE2138804A1 - Electric contact protection device - Google Patents

Description

Applicant: General Electric. Company, Schenectady, New York, NY, USA

Electrical contact protection device

The invention relates to an electrical contact protection in the direction.

Known contact protection devices are used to automatically switch off a live conductor when one comes into contact with this conductor and at the same time with another conductor or earth, so that an injury occurs an electric current could flow through the body. Usually institutions of this type operate in such a way that one Touch by a person through whose body at least a small portion of the flow is to the opposite side of the Circuit leads without going through a predetermined part of the conductor step through, for which a detection device is provided. As a result, there is an asymmetry of the entire current passage all conductors at the location of the detection device. This is because some of the current is shunted around the Detection device is derived along a path that runs through the person's body.

In order to achieve speed and detection sensitivity 109887/1353

aim, which is necessary to protect the person concerned, the contact protection device must target extremely small current differences or address extremely small asymmetries in the current in the shortest possible time. The unbalance of the currents becomes common detected by a differential transformer containing a winding that surrounds all of the conductors in the circuit and serves as the secondary winding of a transformer of which the circuit conductors serve as primary windings. If the algebraic sum of the currents in the circuit item zero is, the voltage generated in the secondary winding is also zero. When a certain stream is shunted around The differential transformer is derived, however, occurs a signal voltage across the secondary winding. Since this signal voltage is usually very small, an amplifier or a very sensitive relay (or both devices) can be used to achieve a usable output power. The output signal of the amplifier or the relay is passed on to an electrically operated device, which Contacts in series with one or more of the conductors will open, removing the tension and protecting the person from a blow is protected. There are also other verification devices for Evidence of an asymmetry of the current flow known, which can also be used in this context.

Known contact protection devices are usually used in two ways. In a first type of installation, the device is provided in a suitable casing, for example in a metallic housing, which is arranged at a desired location for the input cable and output conductor, which are connected to the relevant electrical load, for which a protection against accidental contact is intended. This requires the use and installation of a separate housing in addition to the usual switch panel housing, which is used to accommodate and arrange the control and protection device for the power that is to be fed to a building or part of a building and which contains electrical protection devices, which others circuits supply, ^u £ ie no Berührungsschutzeinrich-

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is required. In the second type, the contact protection device is designed to be portable, so that it has its own housing and having conductors and connection means for connection to a given voltage source, and output terminals or base for connection to the loads to be protected. However, this type is not intended for permanent installation intended or suitable.

In each of the cases mentioned, it can be seen that the contact protection device requires a special housing and input and output connections. With a permanent installation Such a protective device must be suitably attached to the wall of a building and with a ladder or other Connection device to be connected to the switchboard and the load "center, which the other protection devices for the building or part of the building.

Known protective devices of this type also contain a device to hold the various components and the wiring, a part of which is installed during the installation is used to connect the components.

It is therefore the object of the invention to provide an electrical contact protection device indicate, which is designed completely and very compact, and which the user during installation only needs to make as few connections as possible. The facility is said to be readily available as a unit in Existing switchboard arrangements with protective circuits and in " Load distribution points can be installed. It should be in the Device a circuit breaker part of conventional design are provided, the arrangement of which is essentially unchanged should be in the form of conventional circuit breakers, so that the contact protection device can be easily integrated into existing ones Protective devices and load centers can be installed. The touch protection device should have the following components include: circuit breaker ,. Detection device for an asymmetrical current flow, an electron switch and a Electrically operated device for tripping the circuit breaker, whereby all components against damage by incidental physical contacts are protected, and the ge

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all wiring for connecting the components in the appropriate Way is covered and protected so that the only exposed conductive parts are the terminals / which the user must connect when installing the device. a detection device for asymmetrical current flow, a very sensitive relay or an electronic switch, as well as an electrical actuator for the circuit breaker, which components are all arranged in a uniform housing, which has a shape and dimensions, which is suitable for an arrangement of the device at conventional switching points. Furthermore, this touch protection device should the main components each occupy a place which generally corresponds to that given by a monopolar usual circuit breaker is taken, which for an arrangement in a conventional circuit device of the mentioned type is suitable.

In the first embodiment of the invention, the contact protection device contains a part with a circuit breaker, whose housing corresponds in shape and dimensions to that of a conventional circuit breaker for a Attachment to a switchboard panel is suitable. This touch protection device contains additional parts in addition to the circuit-breaker part, which are connected to it as a unit and which contain an electrically operated tripping device for opening the circuit breaker, as well as a device for Generating electrical signals to a predetermined signal to be released when a predetermined, relatively small asymmetry of the currents occurs in predetermined conductor parts. Furthermore, a sensitive relay or an electronic switch is provided in order to control the electrical release device excite when the said signal occurs.

In a special embodiment of the invention, the parts contain the electrical part in addition to the circuit breaker part Release device in a first laterally adjacent chamber, as well as a signal amplifier or an electron switch in a second laterally adjacent chamber. Further

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the signal generating device contains a differential transformer, pass through the conductor of the circuit controlled by the circuit breaker.

According to another feature of the invention, the contact protection device provided with a device for arrangement and connection with a switchboard panel, which a contains central row of connector plugs that connect to the voltage source are connected, as well as a series of retaining hook parts, which are provided at a distance from the connector plugs is to keep circuit breakers in the switchboard bay. The touch protection device can, however, also instead have devices that can be screwed by plug-in devices.

The circuit breaker part of the touch protection device is provided with a plug contact and with at least one Holding device, which can grip a hook part of the switchboard panel, around an arrangement of the touch protection device to enable on the switchboard panel through plug-in contacts. The adjacent parts of the touch protection device, which enclosing the electrical actuator and the amplifier are provided with clearance openings which the Allow attachment of the assembly in the manner of multi-pole circuit breakers and occupy a space that is usually is required for single-pole circuit protection devices of the usual type.

As will be explained in more detail below, contains a touch protection device according to the invention the circuit breaker part a multi-pole circuit breaker, for example a three-pole circuit breaker, during the remaining part of the device is formed in the manner described above.

The invention is to be explained in more detail with the aid of the drawing. Show it:

1 shows a view of a switchboard panel used for protective purposes of the usual type, with a contact protection device arranged therein according to the invention, which panel field in the installed state on a vertical wall surface represents

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is placed but the cover is omitted?

FIG. 2 shows a side view of the input part of the contact protection device in FIG. 1;

FIG. 3 shows a circuit diagram of the contact protection device in FIG. 1; FIG.

4 shows a perspective view of the contact protection device in Fig. 1, wherein the holder of the switchboard panel is shown separately;

5 shows a circuit diagram of the connections between the contact protection device in Fig. 1, the main lines and the neutral connection line of the switchboard panel; and

6 shows a circuit diagram of a modified exemplary embodiment of the invention, wherein a contact protection device with a number of secondary circuit breakers in connection and therefore enables contact protection for a corresponding number of separate circuits, while the Switchboard field also contains a device for supplying energy to other circuits that are not connected to the touch protection device stay in contact.

The control panel field, which is shown in FIG. 1, is used for protection purposes and consists of a box-shaped metallic housing IO surround. An upper insulating carrier 11 and a lower insulating carrier 12 carry two arranged parallel to one another Busbars 13 and 14. The busbars 13 and 14 are provided with screw-on connection connections 15 and 16, which are used to connect the panels 17 and 18 for the power supply. The housing 10 also carries a connection device, the consists of a neutral rail 20, which is connected, for example, by a clamping device 21 and a cable! 22 is attached to the housing 10, which connector for connecting the rail 20 to a neutral input conductor 23 is used, which is grounded at 23A. A tubular metallic sleeve 24 surrounds the rail 2O and carries a number of clamping screws 25 by which a conductor is clamped can be, the end of which into an opening, not shown

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which is provided in the side wall of the sleeve 24 is used. The neutral rail 20 and sleeve 24 are common electrically connected to the housing 10.

The bus bars 13 and 14 have a number of transverse ones Connecting strips 27 (of which only one is shown), which end in protruding, transversely extending contact nippers 28, of which only two are shown are. The housing IO also contains a support device

29 (Fig. 4) showing a series of inwardly bent hook parts

30 on each side to perform in a known manner 32 to hold (compare US-PS 3403 301 and 3,463,967).

The circuit breakers 32 have an input connection with ' a base, not shown, between the jaws of which the contact blades 28 can be inserted. The circuit breakers 32 have output connections with clamping screws 32Ά with which the conductor ends, not shown, can be pinched, which lead to the electrical load caused by the relevant Circuit breaker is controlled.

The passage of current through one of these circuit breakers takes place in the following way. The input current flows through conductors 17 and 18 to busbars 13 and 14 »The current flows from the contact blades 28 to each of the circuit breakers 32, through the output terminals 32Ά of the circuit breakers 32 and to the relevant load, and back from the relevant load " via the neutral rail 20 to the neutral conductor 23. For phase-to-phase loads, the load would be between the conductors 17 and 18 connected by a two-pole circuit breaker, the current through one of the busbars 13, 14, through one of the poles of the circuit breakers, through the load and back to the other of the bus bars 13 and 14 via the other pole of the two-pole circuit breaker flows.

According to the invention, the contact protection device 36 according to the invention has a substantially rectangular insulating one Housing with a number of chambers. The specific shape, type of construction and assembly of the insulating Housing can be designed in different ways.

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Due to the special shape and construction shown, however, certain advantages can be achieved.

According to a preferred embodiment of the invention « the insulating housing of the contact protection device 36 contains two essentially rectangular housings 37 and 38 as well as a third L-shaped housing (Fig. 4). The housing section 37 contains a conventional circuit breaker with its insulating Housing which is essentially rectangular and includes a main part 37A and a cover part 37B (Fig. 2), which closes the open side of the main part 37A and carries the parts of the circuit breaker, as well as the operating device 40 of the circuit breaker.

Housing section 38 also includes a self-contained, generally rectangular, insulating housing of two parts, similar to the part 37 for the circuit breaker, with a main part 38A and a cover part 38B. An actuating device 41 is also provided here.

The remaining part of the housing of the touch protection device 36 includes a generally L-shaped housing portion 39 formed by interengaging upper and lower Insulating pieces 42, 43 (Fig. 4) is formed. The insulating pieces 42, 43 have substantially flat lower sides and upper sides and side walls extending perpendicular thereto. The insulating pieces 42, 43 are then, for example, by screws 44 attached to each other. The housing sections 37, 38 are joined together and on the remainder of the housing section with the aid of transverse bolts or rivets 45 held.

From Fig. 3 it can be seen that there are four main chambers in the insulating structure according to the invention are. Namely the chamber 47 for the circuit breaker, the chamber 48 for the electrical tripping device, the chamber 49 for the amplifier or the electronic switch, as well as the chamber 50 for the detection device for detecting the asymmetry of the current curve, which contains a differential transformer 60. In the illustrated embodiment, the chambers are 49 and 50 are adjacent or are in connection with one another.

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It should be noted that the shape and arrangement of the chambers changed can be achieved, although certain advantages can be achieved by the illustrated preferred embodiment.

The housing section 37 of the contact protection device 36 according to the invention essentially contains a conventional circuit breaker (US Pat. No. 3,288,965). The housing section 38 has a housing similar to the housing of the housing section 37, which is why the same housing and actuating parts can be used for it. In any case, however, all parts of the housing for the contact protection device 36 are rigidly and permanently connected to one another in order to form a housing unit which is secured against unauthorized access and protects the components contained therein, which will be described in more detail below. The g only exposed portions or conductors are the ones that are to be used in the isolation of the device, namely two terminals for connecting the circuit for the power supply and two terminals for connection to the conductors for the power supply to the load.

The housing section 37 (Fig. 3) of the touch protection device contains a circuit breaker, which is known per se Way can be designed. According to the invention, however, the housing section 37 contains contact springs 37C for insertion of the stationary contact blade 28. A corresponding opening is formed in the housing. The housing section 38 also includes an opening 38C, and the housing portion 42 of the housing portion 39 has an opening 42A. Sections 37 ■ and 38 and part 42 have retaining parts which can be engaged under the hooks 30 of the control panel. Because of these mentioned devices, the contact protection device can be arranged in a conventional control panel field by hooking it under selected hooks 30 and inserting a contact knife 28 into the contact springs 37C.

The housing part 37 (FIG. 3) contains, in addition to the contact springs 37C, separable contacts 52A and 52B and one connected in series Release device 53 and a connecting screw 54.

An actuating device 40 (Figs. 2 and 4) is also

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if provided, to manually actuate contacts 52A, 52B to be able - The actuating mechanism used for this is not shown, as it can be a common mechanism; (See U.S. Patent 3,288,965). The release device connected in series 53 can be a temperature-sensitive device or a device of a type known per se that responds to magnetic forces, or a complicated device which is designed to remove the wiring and / or the load attached to the circuit breaker is connected, protects against unusual current conditions. If these protective functions are used during the installation, are not required, the triggering device 53 can be omitted if the actuation mechanism for the contacts is designed so that switching can take place by an electrically operated device, as will be described shall be.

Housing section 38 contains a shunt trip device or a coil 55 which is connected in such a way that when energized the circuit breaker 37 is triggered and the contacts 52A, 52B are opened automatically. The shape and arrangement of the coil and release mechanism can be different Manner (see e.g. US Pat. No. 3,256,407). The housing section 49 contains an electron switch 56 to be described later.

A test switch 57 is also arranged in the chamber 48 in such a way that it is actuated by the actuating device 41 can be and is biased into the open position by a spring, not shown, so that the actuating device 41 is always in the open position when there is no manual operation. In the chamber 48 there is also a resistor 58 is provided for a purpose to be described, as well as a connection screw 59.

The housing part 42 carries connecting members 61 and 62 in order to be able to connect conductors 63, 64 which lead to a load 65 .

As shown in Fig. 3, a conductor 54A extends from the terminal 54 to the terminal 61, thereby making a connection

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is present via an error signal generating device with a differential transformer 60. The current path runs from the terminal 61 via the load 65 and the conductors 65 and 64, back to the terminal 62 and from there again to the differential transformer 60 via a conductor 59A which connects the terminals 62 and 59. The connection 59 is connected to the neutral rail 20 via a conductor 67. As can be seen from FIGS. 1 and 4, the conductor 67 is integrally connected to the contact protection device 36 with a curved course in order to simplify the installation. Optionally, a conventional wire connection can be provided, as will be described in connection with the exemplary embodiment in FIG. 6. In any case, it is apparent that two pipe connections are provided, a first lead terminal comprising a base 37C, and a second line connection% with a conductor 67 or other connecting device. Two load connections are also provided, namely a first load connection 61 and a second load connection 62.

The output of the differential transformer 60 becomes fed to the electron switch 56 via conductors 68 and 69. The electron switch 56 is energized via the conductors 70, 71 which connect the electronic switch in parallel to the power conductors 54A and 59A. The output of the electron switch 56 is fed to the electrically actuatable triggering device 55 via the conductors 72, 73.

The electronic switch can be of any desired design. form and does not necessarily have to be an electronic device so long as the low power input signal from differential transformer 60 reaches a predetermined Size can be used to actuate the tripping device 55 in order to trip the circuit breaker 37 cause.

An electron switch that can be used for this purpose is, for example, from the manual for silicon-controlled rectifiers by General Electric Company, 4th Edition 1967, pages 166-167.

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When the circuit breaker 37 is closed during operation and the load 65 is connected, a hazardous situation is indicated at the point 75 if a person accidentally comes into contact with conductor 63 while it is in contact with earth or closes a current path that leads to conductor 67 returns a path other than through conductor 59A. It can be seen that the current flowing through the person is through the primary winding 54A passes but not through primary winding 59A. The circuit to the neutral conductor 23 is via the ground is closed by a "shunt" of winding 59A an imbalance exists between the currents on conductors 54A and 59A, causing a signal voltage from the differential transformer 60 is given-. When this signal voltage is sufficient Has size, the electronic switch 56 is operated. An actuation of the electronic switch 56 causes an actuation the coil 55, which switches the circuit breaker 37 and interrupts the connection to the conductor 54A, so that on the conductor 63 no voltage is applied and also no longer on the person who is endangered by contact.

To understand how the facility works after installation To be able to test, a switch 57 is provided in the chamber 38, which is closed by actuating the actuating device 41 can be. This causes current to flow from conductor 54A on the load side of the differential transformer passing through the neutral Rail can flow back via conductor 76 and resistor 58 without having to go through differential transformer 60 again flow. Therefore a controlled earthed fault current is generated. The value of resistor 58 is selected to accommodate this fault current has a predetermined small value, for example 7 mA, corresponding to a current strength against which a person is protected shall be. This again results in a difference or an asymmetry, whereby the device is actuated and its effectiveness can be demonstrated. '

According to the invention, the electrically actuatable device 55 can be provided in the circuit breaker 37. One special compact and economical structure can be achieved,

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while the winding of the coil 55 is arranged in such a way that a magnetic flux is generated which acts on an armature which is already is provided in the circuit breaker, for example on the armature 24 of the circuit breaker 10 (Fig.) In the aforementioned US-PS 3 288 965. For this purpose, the winding of the coil 55 can be provided on the field core 37 of the aforementioned prior publication. Other equivalent arrangements can also be used.

FIG. 6 shows another exemplary embodiment of the invention, which provides additional advantages over the exemplary embodiment in FIGS. 1 to 5. A casing 110 is provided which carries connections 115 and 116 which correspond to connections 15 and 16 in FIG. 1. Further, the first neutral rail is ä ne provided 124, which is connected to a neutral conductor 123 via a terminal 122nd A second, neutral rail 124A is arranged on the casing 110, for example by means of an insulating block 124A ¹ , but is not connected to the casing 110 in an electrically conductive manner.

Two main busbars 113 and 114 are insulated in the enclosure 110 and have laterally extending connecting members 128 which are connected to the busbar 113 or 114 are connected in the manner indicated so that they are alternately connected to the bus bars 113 and 114 and two each adjacent contact members 128 are connected to different busbars. J

In the exemplary embodiment of a contact protection device 136 according to the invention, which is used here, there is a similar construction as provided for the device 36 in FIGS. 1 to 5 with the exception that an additional circuit breaker pole 137A, which is connected to simultaneously operated with pole 137 and triggered at the same time. Therefore, poles 137 and 137A form a two-pole circuit breaker, wherein a pole 137 is connected to a contact member 128 which is connected to the bus bar 113 in connection, while the other pole 137A is connected to a contact member 128 which is connected to the busbar 114. The contact protection device 136 also contains a chamber U8 for an electrical Trip device, which device how the device

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213880A

55 in the embodiment in FIGS. 1 to 5 is designed to operate the two-pole circuit breaker 137-137A. The contact protection device 136 also contains a chamber 139 for an electron switch 156, which is not shown, and how the switch 56 in the exemplary embodiment in FIGS. 1 to 5 can be designed. In addition, the device 136 contains a chamber 50 for receiving a differential transformer, not shown, which can be designed like the transformer 60 in FIGS. 1 to 5. The secondary winding of the differential transformer in this case surrounds three conductors 154A, 154A 'and a conductor, not shown, which is connected between terminals 162 and 162A and connects conductors 167 and 167A. Therefore, a magnetic core is provided around which the conductors 154A, 154A ¹ and 159A are wound and serve as primary windings. A fourth winding 160A is also wound around the core and serves as a secondary winding so that a signal voltage is generated if there is an imbalance in the currents in the primary windings.

Terminals 161 and 161A are connected to a second set of bus bars 165, 166 by conductors 163 and 163A, where a connection is made through terminals 167 and 168. The busbars 165 and 166 are provided with contact parts 169, similar to the contact parts 128 of the bus bars 113 and 114. A number of circuit breakers or switching devices such as 170 and 171 may be provided in the lower portion of the enclosure 110 and connected to the bus bars 165 and 166. The differential transformer 160 is connected to the power switch 156, the output of which is the electrical trip device 155 controls. A test switch like the one in FIG. 1 to 5, which the actuating device 41 and the contacts 57 auf -, / si.3t, is also preferably provided in chamber 138.

The contact terminals L69 in the lower portion of the envelope llö can be connected to either single pole circuit breakers such as switches 170 or double pole circuit breakers 171. The two-pole circuit breaker 171 controls a load which, as a result, is connected across the two busbars 165, 166 ir, t, the load supplied by the circuit breaker 170 is between

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between this circuit breaker and the neutral conductor 167.

It can be seen that the neutral current for all loads supplied by the lower portion of the distribution center in Figure 6, that is, bus bars 165 and 166, through conductor 167 to terminal 162A, and then through the differential amplifier across the conductor 159A to terminal 162, and then via conductor 167A to neutral main bus bar 124. Therefore, any current flowing to earth via another path, for example through a person in contact with an earthed metal part, causes an imbalance in the current state in the differential transformer. This applies to loads with 220 or 110 volts. The neutral bus bar 124A is attached to the casing 110 ^{by an insulating piece 124A 1.} It is electrically isolated from the enclosure 110 so that the only current path from the neutral bus bar 124A to the neutral bus bar 124 is through the insulated conductor 167 and the conductor 167A.

During the lower portion of the load center in Fig. 6 the bus bars 165 and IG "and their associated contact terminals and circuit breakers in the same enclosure as the upper part of the load center with the busbars 113 and 114, their Contains contact connections 128 and circuit breakers, as well as the electrical contact protection device 136, it is however evident Lich that this arrangement can be placed in its own housing along with the neutral bus bar 124A, and that conductors 163, 163A, 167 and 167A extend between these two sheaths. As in the embodiment in FIGS. 1 to 5, the connection between the electrical contact protection device and the corresponding busbars done either by plug contacts or by screw connections. In the embodiment shown in FIGS the chamber 48 serves to accommodate the electrical triggering device 55 for triggering the circuit breaker 37 when it occurs predetermined states, and also serves to enclose the test switch 57 in the manner described. However, it is can be seen that the test switch if desired in other

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Chambers can be provided.

If desired, the contact protection device, in particular the device shown in Fig. 6, a two-pole circuit breaker to contain all the circuits of one to supply the given load center. In this case the touch protection device would act as a main switch and all of them The circuits supplied in this way would be protected by electrical contact protection. Further the contact protection device in FIGS. 1 to 5 or in FIG. 6 can be arranged in its own outer housing, with the conductors such as the conductors 17 and / or 18 and a neutral conductor such as the conductor 23 directly to the contact protection device are connected without separate busbars.

Godfather ηtan's sayings

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Claims (9)

2138B04 -17- claims IJ Electrical contact protection device with an essentially rectangular housing made of insulating material, with a contact-actuating circuit breaker in the housing, with an electrically actuatable device in the housing to open the circuit breaker when the electrically actuatable device is energized, with an electronic switching device in the insulating housing , which is connected to the electrically actuatable device, with a device for generating a signal in the housing as a function of the occurrence of a predetermined asymmetry of the current flow in a number λ of conductors, and with devices for connecting the device generating the signal to the electronic Switching device, characterized in that first and second externally accessible line connections for connection to the supply network are provided for the contact protection device, and the contact protection device is the first and second externally accessible load connections for connection to a load circuit controlled by the circuit breaker, that first electrical line devices in the housing which contain the circuit breaker connect the first of the line connections to the first of the load connections, that second electrical line devices connect the second of the externally accessible line connections with the second "of the externally accessible load connections in the housing, so that the first and second conductor devices each contain a part which is assigned to the device for generating a signal in the event of an asymmetry of the current flow, so that a passage of a predetermined Current from the first of the load connections to the second of the line connections through a path that does not contain the conductor part which is assigned to the signal generating device, a predetermined asymmetry of the currents in the first and z generated wide conductor parts, so that the signal generating device emits a signal and actuates the electronic switching device, and since / 3 the actuated electronic- = switching device with a voltage jellyfish ! 0 0 Π 8? / 1: j £ ¹ y. · the electrically actuatable device connects to the electrically actuatable device to operate and to open the circuit breaker, so that the supply voltage from the first Load connection is switched off. 2. Contact protection device according to claim 1, characterized in that g e identifier The housing has a discrete chamber for the circuit breaker which has insulating wall members which includes the circuit breaker from the electrically actuatable device, from the electronic switching device and disconnect it from the earth fault signaling device. 3. Contact protection device according to claim 2, characterized in that g e identifier Inet that the chamber is a first elongated and substantially rectangular chamber for the circuit breaker is that the contact protection device also has a second elongated and substantially rectangular chamber for the electrically actuatable device, and that a third elongated, substantially rectangular chamber for the electronic Switching device is provided, with all chambers in a substantially parallel plane laterally to one another extend. 4. Contact protection device according to claim 3, characterized characterized in that the housing includes a second housing part which is practically the same shape and size like the first housing part and is arranged along the first housing part, and that the second housing part, which the second Forms chamber, contains at least the electrically operated device. 5. Contact protection device according to claim 4, characterized in that the second housing part contains a test switch, which has an actuating device, is accessible from the outside of the housing, and that this switch in the closed Sustancl a predetermined asymmetry Ί-3 ätc.'iiivarlaufs in dar 3ignaler.2eugi: mgsainrichUimg causes, · ι .1: '-iciVilh ^ fäL;. ·: ;;; - Lt d; .r Fäacührui': ./-B^hütseinrichtung display -19- 6. Contact protection device according to claim 5, characterized characterized in that the actuating device of the circuit breaker and the test switch are practically the same are designed and arranged so that the protective device in a switchboard field with the circuit breaker module unit can be arranged, taking up the space that is provided for a conventional circuit breaker, and that the second housing part also occupies a space which is provided for a conventional circuit breaker, the actuating device of the test switch is in the same position that would be occupied by the actuating device of a conventional circuit breaker. 7. Contact protection device according to one of the preceding claims, characterized in that it is intended for a switchboard field serving for protective purposes, that at least one busbar is arranged insulated in the housing and means for connecting a number of electrical Circuit control devices that contain an elongated neutral busbar is arranged in the housing and has means for connecting a number of electrical conductors, that a first connecting device connects the first of the load connections of the protective device to at least one of the busbars connects, and that a second connecting device connects the second of the load connections of the protective device to the neutral one Busbar connects. 8. Contact protection device according to claim 7, characterized characterized in that the signal generating means is a differential transformer having a magnetic core with a Has window and through which a conductor runs which is connected in series with each pole of the protective device, that also the neutral connecting device runs through this, and that a secondary winding a signal depending on an unbalance of the current waveform that occurs in all conductors leading through the window. 109887/1353 9. Contact protection device according to claim 8, characterized characterized in that the protective device has an insulating housing in which the contact protection device and the differential transformer are included / that the only externally exposed connecting means, which from the housing, means for connection to the first and second busbars is that means for connection the first neutral busbar is provided / and that a device for connection to the second neutral busbar is available. 109887 / 13S