DE69508364T2 - Modular auxiliary device for modular load switches - Google Patents

Abstract

In an auxiliary modular device for modular circuit-breakers, the mode of operation of a switching contact of the auxiliary device can be preset from two modes of operation by means of a cam selection device operable from the front of the auxiliary device, and an indicator flag facing the front and a test button operated from the front enable the functionality of the equipment and the preset mode of operation to be checked. <IMAGE>

Description

The present invention relates to a modular auxiliary device for modular circuit breakers according to the preamble of claim 1, as known for example from DE-A-38 20 113.

It is known that there are modular electrical devices on the market, also called DIN modules, for side-by-side installation on a rail, which comply with this standard.

These electrical devices essentially consist of modular circuit breakers with thermomagnetic protection and various protection modules.

However, there is a wide range of auxiliary equipment, in particular there are modules for operating auxiliary indicator contacts or simple auxiliary contact modules.

The modules are formed by housings each formed by two coupled half-shells housing one or more auxiliary switching contacts, terminals for connecting the contacts to external cable ends and kinematic devices causing the contacts to switch.

These kinematic devices are mechanically interlocked with at least one power switch module, due to the positioning of the auxiliary module next to it and the subsequent coupling with the kinematic devices of the power module.

In particular, a first gear connection consists of the mechanical coupling of a lever for manual (or motorised) adjustment and tripping of the circuit breaker with a same manual lever for switching the auxiliary contacts, a second interlocking connection consisting of the coupling of a device for automatically tripping and opening the circuit breaker with a same device for tripping the auxiliary contacts.

It is noted that in automatic circuit breaker modules, the internal kinematic devices are such that the action of the thermomagnetic protection devices and the differential protection devices on the device for tripping and opening the circuit breaker causes the return of the adjustment lever to the trip position.

This occurs with a certain delay due to the structure of the kinematic devices and the greater inertia of the adjustment lever compared to that of the devices carrying the movable contact, which opens much faster.

To meet different installation requirements, modules with auxiliary indicator contacts are available on the market, where an auxiliary contact can act in two ways:

A) (changeover mode): the auxiliary contact changes its own position for each opening or closing of the circuit breaker contacts (the auxiliary contact closing on one or the other of two fixed contacts), regardless of whether the opening of the circuit breaker contacts occurs due to a manual trip or the operation of the protective device (trip of the relay),

B) (Relay trip mode): the auxiliary contact switches only when the protection device is operated automatically (relay tripping).

The required operating mode can be selected and set by means of a latch operable by a screw on one side of the auxiliary contact module, the axis of rotation of which is perpendicular to the plane in which the modules are arranged side by side.

This arrangement, dictated by structural requirements, has the first disadvantage that, once the modules are installed side by side on a rail, it is no longer possible to modify the operating mode of the auxiliary contact.

Furthermore, even if there is a window opening on the front allowing the position of the latch and consequently the selected operating mode to be identified, there is neither a visual indication of the actual position of the auxiliary contact nor, more importantly, is there any way to verify that the auxiliary contact has switched upon the relay tripping or that the auxiliary module behaves according to the desired operating mode.

Another disadvantage of the known auxiliary modules, if they have two changeover contacts, is that the order in which one contact switches relative to the other is not always the same, but changes according to the switching direction.

However, in many applications it is suitable or necessary that the two contacts always switch in the same order, regardless of the switching direction, at least when the relay is triggered.

The modular auxiliary equipment of the present invention, which has a device for selecting the operating mode of the contact that can be operated from the front of the module, even when the module is installed next to other modules, avoids these disadvantages and these limitations.

The device comprises a screw cam capable of rotating through a predetermined arc limited to 90º and assuming two stable operating positions, and a holding device for locking the kinematic device. Locking is selectively prevented by the engagement of the holding device with the cam.

The cam is rotatably housed in a base formed without any undercut by two housing shells arranged side by side, with its axis parallel to the plane of the juxtaposition of the modules and with an operating head directed towards the front of the auxiliary module.

The base further provides for axial positioning of the cam, ensuring that it cannot be lost, and the base further provides for limiting the angle of rotation and biasing the cam to one of two predetermined operating positions.

The kinematic device for switching the contact has a plate-like arm that allows the position of the contact to be seen.

There is also a test button which, by acting on the tripping device of the auxiliary device, allows the tripping of the contact breaker relays to be simulated and the switching of the contact and consequently the pivoting of the plate to be visually checked without the need to use electrical instruments or to subject the system to overload and/or short-circuit conditions.

According to a further aspect of the present invention, a kinematic auxiliary deceleration device is advantageously also provided to ensure that a device with two auxiliary contacts, the switching of one contact is delayed relative to the switching of the other at the event of tripping of the relay for both directions of switching.

The characteristics and advantages of the invention will become clearer from the following description of a preferred embodiment and the accompanying drawings, in which:

Fig. 1 is a perspective view showing a preferred embodiment of a modular auxiliary contact device,

Fig. 2 shows schematically the electrical and kinematic structure of the device of Fig. 1,

Fig. 3 is a graph showing the relationship defined by the kinematic device of Fig. 1 between the rotation and the travel of two elements of the kinematic device,

Fig. 4 is an exploded perspective view of a preferred embodiment of the kinematic device of Fig. 2,

Fig. 5 is an exploded perspective view of a preferred embodiment of a cam for selecting the operating mode for the kinematic device of Fig. 2.

For a better understanding of the problem solved by the invention, Fig. 1 is a perspective view showing a modular auxiliary contact device according to the present invention.

The device is characterized by a housing of a generally flat, rectangular parallelepiped shape with a Front side 1, an opposite back side, two parallel side surfaces, one of which is visible, indicated by a 2, and a further two sides, ie an upper side and a lower side respectively, one of which is visible and indicated by a 3.

The sides of the enclosure are defined in this way with respect to the conditions of installation, which envisage that the module is fixed with its rear in contact with a rail supported by a vertical wall and with its side faces vertically in contact with the side faces of other modules.

The auxiliary module is positioned and anchored to the adjacent modules by means of alignment pins 4, 5 and coupling devices 6, 7, which are preferably, but not necessarily, of the type described in EP-A-0 626 712 and are formed on the side surface 2.

A slot 8 also opens in the side surface 2, with a pin 9 protruding from it for coupling between an internal kinematic trip device and a corresponding kinematic trip device of a circuit breaker module in a known manner.

The housing accommodates at least one switch contact, preferably two switch contacts, kinematic devices for connecting the contacts and terminals for connection to contacts of external cable ends.

The connections are accessible through holes in the housing formed in the bottom and top walls or in both and in a section of the front wall.

In Fig. 1, holes 10, 11, 12, 13 can be seen for the insertion of external cable ends into the terminals and holes 14, 15, 16, 17, 18, 19 for access to the screws for clamping the connections can be seen.

A lever 20 for manual adjustment of the contacts, exposed on the front face 1, is hinged in the housing and mechanically coupled in a known manner to a corresponding lever for manual adjustment and tripping of a circuit breaker module arranged adjacent to the auxiliary module.

According to the present invention, a screw head 21 for operating a cam device for selecting the operation mode of the contact is exposed on the front side 1.

The front face 1 further comprises a window 22 facing an indicator plate operated by the internal kinematic devices and indicating the switched or non-switched state of the internal contact, the operating mode of which can be selected.

The indicator plate provides a positive or direct indication of the state of the contact and of the selected operating mode; if the operating mode is intended to indicate the switching of the auxiliary contact, the indicator plate changes its indication for each manual setting and tripping operation carried out on the setting lever.

However, the indication does not change after a first manual setting operation for any subsequent setting and tripping operation if the operating mode is set to that of switching the auxiliary contact upon tripping the relay.

Manual setting and triggering of the auxiliary module does not allow positive verification of the switching of the auxiliary contact as a result of the triggering of the relay by means of the plate.

To enable this check, the auxiliary module according to the invention comprises a test button 23 directed towards the front of the device.

The test button acts on the internal kinematic device in the same way that the protective operation of an associated circuit breaker module would act on the trip of the relay, causing the switching of the auxiliary contact, which can be verified by the change in the indication of the plate.

Fig. 2 shows schematically the kinematic device of the auxiliary module formed according to the present invention.

The module comprises a first movable contact 24 electrically connected to a connection terminal A and switchable to close or open relative to one of two fixed contacts 25, 26 electrically connected to connection terminals B and C, respectively, and a second movable contact 27 electrically connected to a connection terminal D and switchable to close or open relative to one of two fixed contacts 28, 29 electrically connected to connection terminals E and F, respectively.

The contacts 24, 27 are biased toward the fixed contacts 25, 28 by respective resilient support arms (or contact arms) 30, 31 as shown or by resilient biasing means such as springs to the rest positions in which they are closed, respectively.

The kinematic device for operating the contacts comprises a bistable lever 32 for manual adjustment and release, to which an adjustment rod 34 is articulated, the free end of which presses against the end of a lever 33 of a first class, the other free end of which presses against an axially displaceable rod 35.

The rod 35 exerts a pull on the contact carrier 30 in order to switch the movable contact 24 so that it closes on the contact 26.

The kinematic device is adjusted by pivoting the lever 32 in the direction shown by the arrow M up to a support stop element 37.

When the device is adjusted, the rod 34 and the lever 33 assume the stable positions indicated by the dashed lines and identified by the reference numerals 34A and 33A.

In this state, a release device, shown schematically in Fig. 2, such as a lever 36 with three arms, which is swung anticlockwise by a release control CS (applied by means of the pin 9 of Fig. 1), moves the end of the rod 34 away from the position where it acts on the end of the lever 33 and allows the latter to be swung clockwise, thus allowing the rod 35 to be returned to the rest position by the action exerted by the elastic support arm 30 of the contact 24 which switches to the rest position.

The lever 36 is biased to the rest position by a spring, not shown.

The kinematic device is manually triggered by returning the lever 32 to the rest position.

The state of the movable contact 24 clearly "copies" the state of the circuit breaker devices associated with the auxiliary module, regardless of whether they are manually operated or operating automatically.

The operating rod 35 is coupled by a push-fit to a rod 38 which in turn pushes the movable contact 27, thereby switching it so that the contact closes onto the contact 29.

In the absence of other restrictions, the contact 27 "copies" the state of the contact 24.

A second kinematic device, which can be optionally deactivated, enables the contact 27 to operate in a different way, i.e. that it only switches when the relay is triggered.

The second kinematic device comprises a lever 39 which is pivoted on a lever pivot point 40 and is coupled to a bolt on the rod 38 through a slot 41.

It further comprises an engagement retaining device 42, shown schematically as a lever with three arms pivoted at 43 and biased by a spring 44 to an engagement position.

When the rod 38 is pushed by the rod 35 and switches the contact 27 so that it closes on the fixed contact 29, it pivots the lever 39, moving it to the position indicated by a dashed line and a reference numeral 39a.

In this position, the end of the lever 39 opposite the slot 41 is engaged by the holding device 42.

A cam 45 attached to the manual adjustment lever engages one of the arms of the holding device 42 and moves it to an inoperative position for positions of the lever 32 near the adjustment position.

This is explained in more detail below; in the event of a manual release, the retainer 42 returns to the engagement position before the lever 39 pivots far enough to prevent engagement.

The lever 39 is then locked in position 39A and consequently locks the operation of the rod 38 in a position that prevents the contact from switching.

On the other hand, in the event that triggers the relay, the release device 36 releases the lever 33, allowing the rod 35, the rod 38 and the lever 39 to return quickly to the rest position due to the elastic biasing of the contact supports 30 and 31, before the pivoting of the lever 32 and consequently of the cam 45 allows the retaining device 42 to return to the engaging position.

Both contact 24 and contact 27 are therefore switched.

Contact 27 therefore acts as a contact that only switches when the relay is triggered.

To enable the contact 27 to further switch in the event of a manual trip, an eccentric cam 46 can be manually rotated between a first angular position at which the cam does not engage the holding device 42 and a second angular position at which it engages one of the arms of the holding device 42, moving it to the inoperative position.

The behavior of the auxiliary contacts and the visual control of the functionality of the module are provided by a boom BB which is fixed to the lever 39 and, as already explained with reference to Fig. 1, is arranged like a plate facing a window 22 which opens in the front of the housing and which indicates whether the contact 27 is closed at the contact 28 or at the contact 29.

If the manual setting and release of the lever 32 are accompanied by a corresponding change in the indication of the plate BB, they make it possible to ensure that the contact 27 is effective and works in a switching mode.

However, it is not possible to check the functionality of the module if contact 27 works only to switch upon the relay triggering.

Furthermore, to enable this check, the auxiliary module comprises a test button 47 accessible from the front of the module (Fig. 1), acting on a lever arm of the release device 36 and, once the module has been manually adjusted, allowing the adjustment rod 34 to be released from the lever 33 so that the two contacts 24, 27 switch and return to the rest position.

The switch is made visible by the change in the display of the BB plate.

Furthermore, there is advantageously a further additional kinematic device which ensures a predetermined operating sequence when switching the two contacts 24 and 27.

The kinematic device, which is very simple, consists of an auxiliary lever 48 pivoted at an intermediate point, with a first slotted end 49 engaging a pin on the rod 38, so that the lever 48, as a result of axial movements acting on the Rod 38 is forced to pivot.

The adjustment lever 32 has, in addition to the cam 45, a second projecting cam (or tooth) 50 which, when the lever 32 is pivoted to the adjustment position, engages a second end 51 of the auxiliary lever 48 and urges the same to hold the rod 38 in the position in which the contact 27 is closed at the contact 29.

In the event that triggers the relay, the engagement between the cam 50 and the end 51 of the auxiliary lever ensures that the movable contact 27 switches to the fixed contact 28 after the movable contact 24 has already switched to the fixed contact 25.

This ensures that the order of switching of the two movable contacts is the same for switching in both the one direction and the other direction, since, in order to generally prevent uncertainty in the switching order, the dimensions of the kinematic device formed by the rods 35, 38 which mechanically couple the two movable contacts are designed to ensure that, for adjustment, the contact 24 switches to the contact 26 before the contact 27 switches to the contact 29.

The locking function of the lever 42 and the delay function of the auxiliary lever 48 can be more easily understood by examining the graph of Fig. 3, which qualitatively shows the relationship that the kinematic devices establish between the rotation 4 of the adjustment lever 32 and the travel S of the rods 35, 38 in the various cases of manual adjustment and tripping (graph I) when switching the contact 27, switching to tripping the relay (graph II) and switching to tripping the relay with a delayed switching of the contact (graph III).

The region φ0-φM defines the different angular positions that the lever 32 can assume while moving from the trigger position to the adjustment position.

The area φ8-φM defines the angular positions of the lever 32 for which the cam 45 prevents the holding device 42 from acting on the lever 39.

The area φ9-φM defines the angular position of the lever 32, for which the cam 50 engages the auxiliary lever 48.

The distances covered S1, S2, S3, S4, S5 define the positions of rod 35 and rod 38, for which the following apply:

S1:- contact 24 is open/closed relative to contact 25,

S2:- the contact 27 is open/closed relative to the contact 28,

S3:- the contact 24 is open/closed relative to the contact 26,

S4:- contact 27 is open/closed relative to contact 29,

S5:- the travel limit value below which the lever 39 cannot be engaged by the holding device 42.

In the case of manual setting (Graph I), the closing and opening of the contacts takes place in the order S1, S2, S3, S4.

In the case of manual release, if the cam 46 If the operation of the holding device 42 is prevented, the closing and opening of the contacts takes place in the reverse order S4, S3, S2, S1.

The auxiliary lever 48, if present, has no effect.

On the other hand, if the cam 46 is arranged for the operating mode to switch only upon the triggering of the relay, the angular position φ8 of the lever 32 corresponds to a travel of the rod 38 which is greater than the engagement travel limit 55.

The contact 27 therefore remains in the switched position, with only the contact 24 switching, namely in the order S3, S1.

In the event of the relay being triggered and in the absence of the auxiliary lever 48, the interruption of the link-like connection between the rod 34 and the lever 33 allows the rods 35, 38 to quickly return to the rest position, independently of the rotation of the lever 32.

The inertia of the kinematic devices and the magnitudes of the preload forces acting in each case define a relationship between the travel S and the rotation φ, which is shown qualitatively by the graph II.

In this case, the lever 32 reaches the angular position φ8 at a point when the travel S of the rod 38 is well below the engagement limit S5.

The order in which the contacts are switched is therefore given by the sequence S4, S3, S2, S1.

If the auxiliary lever 48 is present, graph II still represents the relationship between the travel of the rod 35 and the rotation of the lever 32, but the relationship between the travel of the rod 38 and the rotation of the lever 32 is shown by the graph III.

In fact, it is clear that the rod 38 can only start to move if the lever 32 has reached the position φ9.

Clearly, the order of switching the contacts is given by S3, S4, S1, S2.

It is noted that the auxiliary lever 48 can advantageously be used even in auxiliary modules in which the manual setting lever 32 does not return to the trip position upon the operation of the trip device, i.e. upon the tripping of the relay, but which require manual resetting.

In this case, referring again to Fig. 2, it can be seen that the toothed cam 50 engages the end 51 of the auxiliary lever 48, preventing it from pivoting.

The auxiliary lever 48 in turn prevents the rod 38 from moving.

The switching of the contact 27 is thus prevented until the adjustment lever is manually reset, whereby, in short, the switching of the contact 27 is delayed relative to the switching of the contact 24, which is switched upon the triggering of the relay.

Clearly, in this case, the lever 39 and the device for selecting the operating mode of the auxiliary contact 24 are superfluous and ineffective, since the blocking action of the auxiliary lever 48 prevails over the action of the lever 39, whatever the operating mode set.

Having described the general aspects of the invention 4 and 5 are exploded perspective views showing preferred embodiments of the various kinematic devices and the cam device for selecting the operating mode, respectively.

In the drawings, the various elements corresponding to those of Fig. 2 are indicated by the same reference numerals.

In Fig. 4, the conventional adjustment lever 32 can be easily seen in the form of a drum with an adjustment arm.

Along a rim of the drum there is a recess 45A having a function similar to that of the cam 45 of Fig. 2.

The drum is rotatable on a pin 52 which is attached to the housing, which is not shown, in a known manner.

The adjusting rod 34, which is rotatably mounted on the drum, has an end 53 which engages against a tooth 54 of the lever 33.

The end 53 of the rod is held in contact with the tooth 54 by a pawl 55 pivotally mounted on the lever 33.

The latch 55 is held in the engaged position by a spring 56 and is operated by the release lever 36 which is pivoted together with the lever 33 on a pin 57 fixed to the housing.

The release lever 36 is formed by two bodies 36A, 36B, which are shown as separate bodies but form a single unit.

The body 36A has a pin 9 for operating the release lever from outside the housing, as explained with reference to Fig. 1, and acts on the latch by means of an arm 58.

The body 36B has a second arm 59 on which the end of an arm 60 of the test button 47 acts.

The test button is conventionally made of a plastic material and has a one-piece leaf spring 61 which biases the button toward the rest position.

The button 47 is housed in a seat 62 in a half-shell 63 of the housing in the front thereof.

The leaf spring 61 presses against an inner rib 64 of the housing.

The arm 60 of the test button engages the wall of the housing, limiting the outward travel of the button relative to the housing and preventing the button from becoming lost.

The lever 33 acts on the rod 35 by means of a second lever 65 which is pivoted on a pin 66 fixed to the housing and has a slot 67 which cooperates with a bolt on the rod 35.

One end of the rod 35 has a tooth which engages a leaf spring 30 which carries the movable contact 24 which switches between a closed/open state relative to the fixed contacts, only one of which 26 is shown.

The other end of the rod 35 presses against the rod 38 which consists of a double L shape and has a section arranged parallel to the rod 35.

The end of the portion of the rod 38 that is parallel to the rod 35 has a tooth that engages a leaf spring 31 that carries the movable contact 27 that switches between a closed/open state relative to the fixed contacts 28, 29.

The other end of the rod 38 has a bolt which is coupled to a slot 167 in the lever 39.

The lever 39, which is pivoted on a pin 68 fixed to the housing, has an arm 69 which ends in a plate 70 which opens into a hole in the front of the housing, not shown.

An engagement retainer 42, pivotally mounted on a pin 71 secured to the housing and biased toward the active position by a spring, not shown, locks the lever 39 in the adjustment position.

The holding device 42 has a lever arm 72, the end of which is inserted into the recess 45A of the adjustment drum and, by engaging the drum, moves the holding device 42 to the non-active release position when the drum is in the adjustment position.

The holding device 42 is further deactivated by the rotary cam 46, which acts on an arm 73 of the holding device 42.

Fig. 5 is an enlarged perspective view showing a preferred embodiment of the cam 46 and its support formed by the half-shells of the housing at the front of the auxiliary device.

The need to be able to operate the cam from the front of the housing, given the strict size constraints imposed by the device together with the limitations imposed by the manufacturing technology for molding the housing half-shells, entail the need to overcome considerable technical problems.

The cam 46, which is preferably made of a plastic material, has a cylindrical head 73 which has a groove 74 on an outer side for actuation by means of a screwdriver or similar tool and which is axially extended on its opposite side by a pin 75 of smaller diameter.

A stop and rotation limiting tooth 76 in the form of a cylindrical sector with a diameter equal to that of the head and about 5 mm is formed on the pin 75 adjacent to the head 73.

At the opposite end of the pin 75 there is a cam profile with an actuator tooth 77 which advantageously extends radially relative to the axis of the pin 75 and is preferably aligned radially with the axis of the actuating groove 74.

The cam profile further comprises a non-active sector 78 with an outer diameter larger than that of the pin and an active sector 79 with a larger diameter extending along an arc of approximately 120º and in which there are two notches 80, 81 spaced apart by an angle of 90º.

In the front of the housing half-shell 1, a semi-cylindrical base 82 for the head 73 and the tooth 76 is formed by molding without an undercut and is defined internally by a half-bezel 83 forming a semi-cylindrical support with a diameter equal to that of the pin 75 and with an axial length equal to that of the pin 75 less the axial dimension of tooth 76.

A stop tooth 84, which resembles a sector of a ring, is formed in the base 82 and cooperates with the tooth 76.

A semi-cylindrical base 85 for the head 73 is formed without an undercut in the front of the half-shell 2.

At a suitable axial distance from the base 85, equal to the axial thickness of the tooth 76, there is a support plate 86 which extends to form a semi-cylindrical end support 87 which is coupled to the half-shell 83.

The support plate 86 is fixed to the wall of the half-shell 2 by a rib 88 which extends as far as the semi-cylindrical support 87 to form a stop tooth 89 which cooperates with the tooth 76.

The two teeth 84, 89 cooperate with the tooth 76 to limit the rotation of the head 73 and the associated active cam tooth 77 to an angle of 90º, so that the tooth can assume two end positions, namely an active position in which the tooth 77 acts on the retaining device 42 (Fig. 4) and an inactive position in which the tooth 77 does not engage the retaining device 42, and the retaining device is free to engage and lock the lever 39.

When the head 73 is operated from the outside, it is subjected to a moment which can generate rather large torsional stresses in the body of the device, particularly when the tooth 76 engages the teeth 84 and 89.

This moment is determined by the tooth 76, which is attached to the head 73 to the teeth 84 and 89 without affecting the pin 75 which has a smaller diameter and a limited torsional strength.

The stability of the end positions assumed by the cam is ensured by an elastic arm 90 formed in the half-shell 2 of the housing and ending in a tooth 91 housed in the notch 80 and 81 respectively for the two end positions of the cam.

The foregoing description refers only to a preferred embodiment and clearly many variations may be applied thereto.

For example, the auxiliary device may further comprise a single changeover contact corresponding to the contact 27 of Fig. 2, whose operating mode can be selected from the two indicated.

In this case, all elements enclosed by the dashed line 93 in Fig. 2 as well as the kinematic deceleration device 48, 49, 50, 51 are superfluous.

The arrangements of the terminals and contacts in the housing shown in Fig. 4 and in Fig. 1 may also be different and may correspond to the diagram of Fig. 2, where the terminals open into two opposite sides of the housing.

Finally, the cam for selecting the operating mode may be biased by a pin 75 having a partially round cross-section and a partially polygonal cross-section, the polygonal portion of the pin cooperating with half-beams which are also partially polygonal and partially semi-cylindrical, rather than by a resilient arm such as the arm 90 of Fig. 5 cooperating with the cam recesses or the teeth.

In this case, the relative elasticity of the coupling between the two half-shells is used to ensure the two stable positions, i.e. the active and the non-active, of the cam.

Claims (8)

1. A modular auxiliary device for a circuit breaker for installation on a rail adjacent to the circuit breaker with at least a first auxiliary switching contact and a device (46, 75, 73) for selecting the operating mode of the auxiliary contact between switching which mirrors the switching of the contact of the circuit breaker, and switching solely due to the tripping of the circuit breaker relay, the auxiliary device comprising a housing made of a plastic material, formed from two coupled half-shells and having a front side (1) accessible to the user even when the device is installed, a device (20) for manual setting and triggering, which can be coupled to the contact breaker, and a setting/triggering device (23) which can be coupled to the contact breaker, characterized in that the housing half-shells form a rotary support (87) and an axial support (85, 86) with an axis perpendicular to the front (1) of the device for a cam (46) for selecting the operating mode, and that the device comprises the cam (46), the cam (46) having a shaft (75) rotatably mounted in the support and an actuating head (73) accessible from the front (1). 2. A device according to claim 1, wherein the rotation holder (87) is arranged between the cam (46) and the head (73). 3. A device according to claim 1 or 2, wherein the camshaft (75) has a first rotation limiting tooth (76) for engaging with a second and a third tooth (84, 89) of the housing half-shells. 4. A device according to claim 1, 2 or 3, comprising a resilient means for biasing the cam (46) in a stable manner into one of two predetermined angular positions. 5. A device according to any one of the preceding claims, comprising an indicator plate (BB) kinematically coupled to the first auxiliary contact and facing a window opening (22) in the front face (1) to indicate the position of the first auxiliary contact. 6. A device according to claim 5, comprising a test button (23) acting on the trigger device and accessible from the front (1). 7. A device according to any preceding claim, which includes a second auxiliary changeover contact operative during the changeover which mirrors the changeover of the contact of the circuit breaker. 8. A device according to claim 7, comprising a delay device for delaying the switching of the first auxiliary contact relative to the switching of the second auxiliary contact upon triggering of the adjustment device (20).