EP2282321B1 - Module for measuring the current in a conductor of a low voltage distributor - Google Patents

Description

TECHNICAL AREA

The present invention relates to a module for measuring a current flowing in a conductor of a low-voltage distributor, comprising a current sensor for detecting the current, a microprocessor circuit for processing an output signal output from the current sensor, and a box-shaped module housing accommodating the current sensor and the microprocessor circuit, which is vertical the direction of the conductor is at most as wide as a pole of a pluggable into the low-voltage distributor and connectable to the power line device, the module housing having an opening for the passage of the conductor and an interface with two connected to the microprocessor circuit and connectable to an external power source power connections and an element of a connection for releasably securing the module in the low voltage distributor. The invention also relates to a low-voltage distributor with such a module.

STATE OF THE ART

A module of the type mentioned above for detecting and measuring the current flowing in a conductor of a low-voltage distributor is shown in FIG DE 10 2006 059384 A1 described. This module has a box-shaped module housing in which a current sensor and a microprocessor circuit are arranged. At the rear of the module housing, a recess is arranged, which serves for releasably securing the module on a DIN rail provided in the low-voltage distributor. In the wall of the housing two openings are formed. In the area of the two openings, the housing accommodates two current connections. Through both openings, one of the insulation-free end of two arranged outside the housing sections of a led by an insulation surrounded conductor. The housed in the housing, freed from the insulation ends of the conductor are electrically connected to the two power terminals. The module housing also accommodates a current sensor and a current measuring conductor which is guided through the current sensor and forms a further section of the current conductor. In addition, an interface is held on the module housing, having the microprocessor circuit and connected to an external power source power connections.

Another current measuring and current measuring module is in DE 195 23 725 C2 described. This module is part of a low-voltage circuit breaker, which in addition to two other of these modules also has a three-pole Schaltkontaktanardnung with a switching mechanism. This module contains a housing with an opening through which a switch-controlled phase conductor of the low-voltage distributor is routed. In the housing, a current sensor and an auxiliary power converter, and a printed circuit board with a microprocessor circuit are arranged, which processes the output signals from the current sensor and passes to an interface for feeding into a bus system. Inside the module, the temperature and voltage of the conductor are also determined and transferred to the interface. Data transmitted at the interfaces serve, on the one hand, to control the switch and, on the other hand, to pass on to a bus system with a central control, in which the detected values of the current carried in the current conductor or other parameters, such as voltage, temperature or power, as well as the corresponding data Another switch of the low-voltage distributor can be displayed.

A current measuring module is also in DE 10 2007 006 219 A1 described. This module has a magnetic module for generating a potential-free Output signal which is proportional to the current to be detected, as well as an electronic module with an integrated circuit for detecting and processing the output signal of the magnetic module. The magnetic module comprises a ferromagnetic toroidal core with or without an air gap. Through the toroidal core, a current-carrying primary conductor is guided. The toroidal core may be provided with a current-supplied compensation winding or a current-supplying sensor winding. Additionally or alternatively, magnetic field probes acting as current sensors are used, which are designed above all as Hall probe or inductive magnetic field probe and measure in the air gap of the toroidal core or on the toroidal core the strength of the magnetic flux which induces through the magnetic field of the current flowing in the primary conductor in the toroidal core becomes.

In the technical catalog Smissline "Innovatively installing protective devices with plug-in technology" from ABB Switzerland Ltd, Normelec, Badenerstr. 790, CH-8048 Zurich / Switzerland, a low-voltage distributor is described in which switching and protective devices designed as modular modular devices, such as circuit breakers, residual current circuit breakers and overvoltage and overcurrent protection devices, are installed on plug-in bases. In such low-voltage distribution boards, the electricity supplied from a low-voltage grid is distributed to different consumers by means of the quickly installed, replaced or supplemented built-in appliances. Since the switches are designed as circuit breakers, the current-carrying loads are protected quickly and reliably from the consequences of overload and short-circuit currents. Designed as a residual current circuit breaker switching and protective devices are even able to react in a fraction of a second to the smallest fault currents. Residual current circuit breakers therefore interrupt the fault current before dangers to persons and property can occur. To solve certain distribution tasks, it may be necessary to know the size of the current conducted by a switching and protective device as a function of time.

PRESENTATION OF THE INVENTION

The invention, as indicated in the claims, the object is to provide a current measuring module of the type mentioned, which can be installed with little effort in a low-voltage distribution and which is also characterized by a high level of reliability.

In the current measuring module according to the invention, the lead-through opening extending from a side wall of the module housing through the current measuring module on an opposite side wall of the module housing and designed so that when installing the module in the low-voltage distribution of the provided with a conductor insulation conductor electrically isolated from the module through the opening a terminal of a arranged in the low-voltage distributor Reiheneinbaugeräts is feasible.

Such a module can be used with advantage in low-voltage distributors, in each of which are designed as a modular DIN-mounted switching and protection devices with standardized width installed on mounting rails or sockets. Although in such low-voltage distributors, the poles of the individual devices along the rail or along the socket in series and have only a small - generally amounting to less than one millimeter - distance, the module can because of its suitably formed, the conductor receiving opening without additional Space requirements are placed at the location of the conductor. Because of the arranged on the module housing connecting element, it can be installed quickly in the low-voltage distribution or, if necessary, removed again. In addition, a low-voltage distribution already in operation can be easily retrofitted with such a module and ensures the structure of the module galvanic isolation of the module from the conductor so that it is insensitive to the effect of short-circuit currents in an advantageous manner after installation in the low-voltage distribution.

If the opening is designed in the manner of a slot, a force acting on the module by bending the conductor can be reduced or even completely eliminated.

If the connecting element has a hook or a plug-in part with a dovetail-shaped profile, then the current measuring module can be fixed to a switchgear and protective device or an additional socket of the low-voltage distributor to form a snap or plug connection with low assembly costs.

If the module is to be releasably attached to a switching and protective device of the low-voltage distributor, which has a double-decker terminal with two terminal compartments for connecting conductors, then it recommends itself, the connecting element designed as in the direction of the conductor aligned, pluggable web. When installing the module in the low-voltage distribution board, the bridge is inserted into one of the two terminal compartments and releasably secured in the terminal together with the current conductor routed through the module into the other terminal compartment by means of a terminal screw. Since the web consists of insulating material and is held on the module housing, a temperature sensor can be arranged on the guided into the terminal space end of the web, which detects the terminal temperature of the switching and protective device. The temperature sensor has an output which is connected via a data line accommodated in the web to a microprocessor circuit arranged in the module. In order to secure the module detachably connected to the switching and protective device via the terminal bar particularly effective against rotation, a pin-shaped fuse element can be arranged on the module housing, which is guided during installation of the current measuring module in a typically formed as an adjustment housing recess of the switching and protection device ,

The module can be fixed directly to the conductor when the connecting element is designed as a recessed in the module housing screw and has a feasible in the lead-through terminal screw. After attaching the module to the conductor, the module can be clamped to the conductor when tightening the terminal screw. The module housing acts as a terminal frame of the screw terminal. In order not to damage the conductor when jamming, it is advisable to use a plastic clamping screw. With such a clamping screw, a defined clamping force can be achieved particularly easily.

So that the module can be supplied with energy independently of the low-voltage distributor, an interface is arranged in the wall of the module housing. This interface has two power line connections, which are connected to the microprocessor circuit and which can be connected to an external voltage source when installed in the low-voltage distributor. A module designed in this way then detects and processes, independently of the operating state of the low-voltage distributor, the one routed in the current conductor Current, possibly also the temperature of the terminal of the current-controlling switchgear and protective device or other physical state variable of the conductor or the device, such as the voltage applied to the conductor.

In order for the module to be able to represent the current current, for example in amperes or as a percentage of the permissible rated current, a display device controlled by the microprocessor circuit is arranged on the surface of the module housing.

Advantageously, the interface further comprises two data line connections for the transfer of digital data, since then a data communication of the current measuring module or other current measuring modules of the low-voltage distributor is ensured with a higher-level central unit.

A low-voltage distributor having at least one of the above-formed current measuring modules can be manufactured particularly easily if the module is releasably secured to an additional socket of the low-voltage distributor, the DIN rail mounted device or the current conductor.

Does the module a hook or a plug-in part with dovetail-like profile and has the releasable attachment to the hook or the male part containing snap or plug connection, in which the hook engages a nose and the male part an undercut of Zusatzstecksockels or the modular device form-fitting, so can The module can be installed very quickly in the low-voltage distributor. Before mounting the conductor, it is only necessary to snap open, postpone or place it on the DIN rail mounted device, which is generally designed as a switching and protective device, or on the additional socket.

If the module has a pluggable web aligned in the direction of the conductor, a particularly firm, detachable fastening of the module to the modular device can be achieved by a clamping connection containing the pluggable web. This concerns above all a low-voltage distributor, which a Reiheneinbaugerät with a Double-level terminal has. The bridge is then only in the first two terminal spaces of the double-decker terminal and the conductor in the serving as a power connection of the modular device second terminal space of the double-decker clamp to arrange. By tightening a terminal screw, both parts can then be fixed quickly, thus fixing the current measuring module in the low-voltage distributor.

If no additional socket is provided in the low-voltage distributor or if the DIN rail mounted device does not have a convenient mounting option, the current measuring module can still be easily mounted in the low-voltage distributor, if the connecting element is designed as a screw terminal recessed in the module housing and has a clamping screw which can be guided into the leadthrough opening of the module. The releasable attachment can then be achieved by a clamping connection containing the screw, in which the module is fixed by clamping the conductor in the screw.

In a particularly advantageous embodiment of the low-voltage distributor, the current measuring module has an interface with two power connections for connecting an external voltage source and two connections for transferring digital data. A communication module arranged in the low-voltage distributor and connected to the interface by a bus system can then connect the current measuring module to an external voltage source and can at the same time also process the digital data transferred from the current measuring module and into a standardized protocol (WLAN, KNX, Profibus or Powerbus) or one transfer customer-specific protocol.

BRIEF DESCRIPTION OF THE FIGURES

Fig.1

eine Seitenansicht einer ersten Ausführungsform eines Niederspannungsverteiler mit einem zum Teil gebrochen dargestellten Schalt- und Schutzgerät, welches auf einem Hauptstecksockel des Niederspannungsverteilers befestigt ist, und mit einer geschnitten dargestellten ersten Ausführungsform des Strommessmoduls nach der Erfindung, welches auf einem Zusatzstecksockel des Niederspannungsverteilers befestigt ist,

Fig.2

eine von links in Pfeilrichtung geführte Ansicht des Niederspannungsverteilers gemäss Fig.1,

Fig.3

eine Seitenansicht einer zweiten Ausführungsform eines Niederspannungsverteilers, bei dem eine zweite Ausführungsform des Strommessmoduls nach der Erfindung mit Hilfe einer Klemmverbindung an einem Schalt- und Schutzgerät befestigt ist,

Fig.4

eine Seitenansicht einer geschnitten dargestellten dritten Ausführungsform des Strommessmoduls nach der Erfindung, welches an einem Stromleiter eines Niederspannungsverteilers befestigt ist, und

Fig.5

eine Seitenansicht einer dritten Ausführungsform eines Niederspannungsverteilers, bei dem eine vierte Ausführungsform des Strommessmoduls nach der Erfindung mit Hilfe einer Steckverbindung an einem auf einer Montageschiene gehaltenen Schalt- und Schutzgerät befestigt ist.

With reference to drawings, embodiments of the invention will be explained in more detail below. Hereby shows:

Fig.1

a side view of a first embodiment of a low-voltage distributor with a partially broken illustrated switching and protective device, which on a main socket of the Low-voltage distributor is attached, and with a cut illustrated first embodiment of the current measuring module according to the invention, which is mounted on an additional socket of the low-voltage distributor,

Fig.2

a guided from the left in the arrow direction view of the low-voltage distributor according to Fig.1 .

Figure 3

a side view of a second embodiment of a low-voltage distributor, in which a second embodiment of the current measuring module according to the invention by means of a clamping connection is attached to a switching and protective device,

Figure 4

a side view of a sectioned third embodiment of the current measuring module according to the invention, which is fixed to a conductor of a low-voltage distributor, and

Figure 5

a side view of a third embodiment of a low-voltage distributor, in which a fourth embodiment of the current measuring module according to the invention by means of a plug connection to a mounted on a mounting rail switching and protective device is attached.

WAYS FOR CARRYING OUT THE INVENTION

In all figures, like reference numerals refer to like-acting parts. The in the FIGS. 1 and 2 illustrated low-voltage distributor has a Hauptstecksockel H and a rigidly connected to the main socket additional socket Z on. In the main socket busbars N, L ₁ , ..., mounted, which are connected to the neutral conductor and the phase conductors of a three-phase system and each feed into a pole of a multi-pole switching and protective device, which is mounted on the main socket H. In addition, the main socket supports auxiliary busbars LA and LB, which are arranged for the common supply of signal and auxiliary contacts of the switching and protective device and further arranged on the main socket H DIN rail mounted devices are provided. Representative of the DIN rail mounted devices only the connected to the busbar L ₁ and, accordingly, to the phase conductor L ₁ switch pole P is shown. In the additional socket Z, the neutral conductor and a protective conductor of the three-phase system associated busbars N and PE are arranged. All busbars are guided parallel in one plane and aligned perpendicular to the plane of the drawing.

The switch pole P has a terminal 10 with a broken terminal frame 11 and a projecting into a terminal space 12 clamping screw 13. A far away from the switch pole P to a consumer, not shown, power conductor 20 is fixed with its free of the conductor insulation 21 end 22 in the terminal compartment 12.

With the reference M is also an off Fig.2 apparent current measuring module called. This module has a predominantly box-shaped module housing 30 into which one Fig.2 apparent opening 31 for the passage of the conductor 20 is formed. This opening is circular or in the manner of a long hole mainly elliptical. Since the current conductor 20 due to the topology of the low-voltage distributor at the terminal 10 having the rear side of the switching and protective device P resp. of the current measuring module M has to be bent downwards mostly, there is more space available in the elongated hole for the current conductor 20 guided through the oblong hole and can thus be reduced or even completely eliminated by a force acting on the module due to the bending of the conductor.

Out Fig.2 It can also be seen that the module housing 30 along the Zusatzstecksockel Z and perpendicular to the direction of the conductor 20 as wide as the switch pole P. The module housing is protected against contact and takes - as if from Fig.1 can be seen - a perpendicular to the direction of the conductor 30 and the passage opening aligned circuit board 40. On the circuit board 40, a current conductor 20 largely coaxial comprehensive ferromagnetic toroidal core 41 and a microprocessor circuit 42 are arranged. In a guided axially through the ring core 41 slot is designed as a Hall probe or magnetic probe current sensor 43 is arranged, whose output is electrically connected to the microprocessor circuit 42. The Microprocessor circuit 42 in turn is out of two Fig.2 apparent data line terminals 51 and 52 connected to a held on the module housing 30 interface 50. As Fig.2 can be removed, the interface 50 also includes two power terminals 53 and 54. These power terminals are on the one hand connected to the microprocessor circuit 42 and the current sensor 43 and on the other hand via a Fig.2 apparent, two data lines and two conductor containing bus 60 and a communication module K connected to a typically 12 or 24 V DC having external voltage source 61. Since the module 30 only detects the magnetic field of the current flowing in the conductor 20 via the ferromagnetic ring core 41, it is galvanically isolated from the conductor 20 and insensitive to the action of short-circuit currents.

On the underside of the module housing 30 a solidified by an unnamed rib of the module housing 30 web 32 is mounted in the free end of a by elastic deformation of the web 32 pivotable snap hook 32 'is formed. The snap hook 32 'engages behind a nose 62 of Zusatzstecksockels Z.

When installing the current measuring module M of the conductor 20 is subtracted from the terminal 10 and subsequently the current measuring module M with a the switch pole P of the switching and protective device facing edge 30 'of the module housing 30 placed on the Zusatzstecksockel Z and counterclockwise around the edge 30' as long tilted down until the snap hook 32 ', the nose 62 of the Zusatzstecksockels Z engages behind. By means of the snap-action hook 32 'and a narrow web 30 "of the module housing, which is molded onto the module housing 30 and snapped into the additional socket Z after being snapped on, the module M is fastened to the nose 62 on the additional socket Z when the snap-action hook 32' is snapped on passed through the opening 31 in the terminal space 12 of the terminal 10 and fixed by operation of the clamping screw 13.

During operation of the low-voltage distributor, the voltage source 61 is connected via the communication module K and the bus 60 to the power connections 53, 54 and thus supplies the current sensor 43 and the microprocessor circuit 42 with operating current. Current flowing to the load through the current conductor 20 is detected with the aid of the current sensor 43. The output signals of the current sensor 43 are fed into the microprocessor circuit 42 and are further processed there in the form of digital signals. In this way, data is formed in the current measurement module M which corresponds to the current load of the current conductor 20. This current load is displayed on a display device 70 controlled by the microprocessor circuit 42, which is arranged on an upwardly facing cover surface of the module housing 30. Typically, the measured current is compared with the permissible rated current and the current load is determined as a percentage of the permissible rated current. If the current load exceeds a limit value, this indicates the display device 70. A particularly simple and yet very effective display device can be realized with the aid of light-emitting diodes 71 to 75, which are distributed uniformly along a straight line in the display device 70. Each of these light-emitting diodes is activated in a certain percentage range, which is 20% each with 5 light-emitting diodes. Accordingly, the LED 71 displays at a current load between 0 and 20% of the rated current, whereas the subsequently arranged light-emitting diodes 72, 73, 74 and 75 in each increased by 20% range of the current load, for example, the light emitting diode 73 between 40 and 60% and the LED 75 between 80 and 100%. Since the light-emitting diode 75 already indicates in a critical range of the current load, it emits a warning signal and, unlike the other four light-emitting diodes 71 to 74, therefore shines not green but red.

The current measurement module M can operate independently of externally supplied data and then does not require the data line terminals 51 and 52.

If, however, the digital measurement values determined by the current measurement module M are to be forwarded, then they are transferred to the bus 60 via the data line connections 51, 52 at the interface 50 and led into the communication module K, in which they are converted into a standardized protocol (WLAN, KNX, Profibus or Powerbus) or any custom protocol.

At the in Figure 3 shown low-voltage distribution board, the current measurement module M is attached to a switch pole P of a switching and protective device, in which it is exploited that the terminal 10 is a double-level terminal and in addition to the terminal space 12 and the terminal chamber 12 'has. The attached to the module housing 30 connecting element is designed as in the direction of the conductor 20 aligned, pluggable web 33. When installing the module M in the low-voltage distribution of the bridge 33 (after removing the conductor 20) into the terminal compartment 12 'and after passing through the current conductor 20 through the current measuring module M, the stripped end 22 of the conductor inserted into the terminal compartment 12. With the help of the terminal screw 13, both the current conductor 20 and the current measuring module M are then fixed to the terminal 10. Since the web 33 as well as the module housing 30 are made of insulating material, and since the web 30 is held on the module housing 30 or molded into the module housing 30, at the guided into the terminal space 12 'end of the web on Figure 3 apparent temperature sensor 44 may be arranged. This sensor detects the temperature of the terminal 10 of the Schalterpols P and has an output which is connected via a mounted on the web 33 data line 45 to the microprocessor circuit 42. In order to additionally secure the module M against rotation, a pin-shaped securing element 34 is arranged on the module housing 30.

In Fig. 4 a part of a low-voltage distributor is shown, which has neither an additional socket nor a switch pole with a suitable mounting option for the current measuring module M. The module can still be easily fixed in the low-voltage distributor, when the connecting element for releasably securing the module in the low-voltage distributor as in the module housing 30 recessed screw 35 is executed and has a feasible in the passage opening 31 of the module M clamping screw 36. The releasable attachment can then be achieved by a clamping connection containing the screw 35, in which the module M is fixed by jamming the conductor in the screw 35.

In the embodiment according to Figure 5 is in the module housing 30, a plug-in part 37 formed with a dovetail-like profile, during installation of the Module M is inserted into the low-voltage distributor in an undercut 63 of the held on a mounting rail 64 Schalterpols P from above. By virtue of the plug connection formed in this way, the module M is likewise fastened detachably in the low-voltage distributor.

LIST OF REFERENCE NUMBERS

H

Main socket

Z

Additional plug-in base

N, L ₁ , ..., PE

busbars

LA, LB

Auxiliary power rails

M

Current measurement module

P

Switch pole of a switching and protective device

B

bus

K

contact support

10

terminal

11

clamping frame

12, 12 '

terminal Facilities

13

clamping screw

20

conductor

21

insulation

22

stripped end of the conductor

30

module housing

30 '

edge

30 "

web

31

Through opening

32

web

32 '

snap hooks

33

web

34

fuse element

35

screw

36

clamping screw

37

Plug-in part with dovetail-like profile

40

circuit board

41

toroidal

42

microprocessor circuit

43

current sensor

44

temperature sensor

45

data line

50

interface

51, 52

Data line connectors

53, 54

power connectors

60

bus

61

voltage source

62

nose

63

undercut

64

mounting rail

70

display device

71, 72, 73, 74, 75

LEDs

Claims (14)

1. Module (M) for measuring a current flowing in a conductor (20) of a low-voltage distribution board, containing a current sensor (43) for detecting the current, a microprocessor circuit (42) for processing an output signal emitted by the current sensor, and a box-like module housing (30) which accommodates the current sensor (43) and the microprocessor circuit (42), which module housing (30) is, perpendicular to the direction of the current conductor (20), at most as broad as a pole (P) of a modular device which can be installed in the low-voltage distribution board and connected to the current conductor (20), the module housing (30) having an opening (31) for passing the current conductor (20) as well as an interface (50) with two current connections (53, 54), which are connected to the microprocessor circuit (42) and can be connected to an external voltage source (61), and an element (32, 32'; 33; 35; 37) of a connection for releasably fastening the module (M) in the low-voltage distribution board, characterized in that the passage opening (31) extends from a side wall of the module housing (30) through the current measuring module (M), to an opposite side wall of the module housing (30), and is designed in such a manner that, when installing the module (M) in the low-voltage distribution board, the current conductor (20) provided with conductor insulation (21) can be routed, through the opening (31), to a connection terminal (10) of a modular device (P) arranged in the low-voltage distribution board in a galvanically separated manner from the module (M).
2. Module according to Claim 1, characterized in that the opening (31) is in the form of an elongated hole.
3. Module according to either of Claims 1 and 2, characterized in that the connecting element is in the form of a hook (32, 32') or in the form of a plug part (37) with a dovetail-like profile.
4. Module according to either of Claims 1 and 2, characterized in that the connecting element is in the form of a pluggable web (33) which is oriented in the direction of the current conductor.
5. Module according to Claim 4, characterized in that a temperature sensor (44) having an output which is connected to the microprocessor circuit (42) is arranged in the web (33).
6. Module according to either of Claims 4 and 5, characterized in that a pluggable safety element (34) is arranged on the module housing (30).
7. Module according to either of Claims 1 and 2, characterized in that the connecting element is in the form of a screw terminal (35) recessed in the housing and has a clamping screw (36) which can be guided into the passage opening (31) and is preferably in the form of a plastic screw.
8. Module according to one of Claims 1 to 7, characterized in that a display apparatus (70) which is driven by the microprocessor circuit (42) and preferably contains light-emitting diodes (71, 72, 73, 74, 75) is arranged in the surface of the module housing (30).
9. Module according to one of Claims 1 to 8, characterized in that the interface (50) has two data line connections (51, 52) for transferring digital data.
10. Low-voltage distribution board having a current measuring module (M) according to one of Claims 1 to 9, characterized in that the module is releasably fastened to an additional plug-in socket (Z) of the low-voltage distribution board, to the modular device (P) or to the current conductor (20).
11. Low-voltage distribution board according to Claim 10, in which the connecting element is in the form of a hook (32, 32'; 37) or in the form of a plug part (37) with a dovetail-like profile, characterized in that the releasable fastening has a snap or plug-in connection which contains the hook (32, 32'; 37) or the plug part (37) and in which the hook engages behind a lug (62) and the plug part (37) engages behind an undercut (63) of the additional plug-in socket (Z) or of the modular device (P) in a positively locking manner.
12. Low-voltage distribution board according to Claim 10, in which the connecting element is in the form of a pluggable web (33) which is oriented in the direction of the current conductor, characterized in that the releasable fastening has a clamping connection which contains the pluggable web (33) and in which the web (33) is arranged in the first (12') of two terminal compartments (12, 12') of a double-level terminal (10) of the modular device (P) and the current conductor (20) is arranged in the second terminal compartment (12) of the double-level terminal, which is used as the current connection of the modular device, and is fixed with the aid of a terminal screw (13).
13. Low-voltage distribution board according to Claim 10, in which the connecting element is in the form of a screw terminal (35) recessed in the housing and has a clamping screw (36) which can be guided into the passage opening (31) of the module (M), characterized in that the releasable fastening has a clamping connection which contains the screw terminal (35) and in which the module is fixed by clamping the current conductor (20) in the screw terminal.
14. Low-voltage distribution board according to one of Claims 11 to 13, in which the module has an interface (50) with two current connections (53, 54) and two connections (51, 52) for transferring digital data, characterized in that the distribution board has a communication module (K) which is connected to the interface (50), connects the current measuring module (M) to an external voltage source (60), preprocesses the digital data transferred by the current measuring module (M) and transfers said data to a protocol, optionally a standardized protocol.

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