Assembly of electrical equipment, notably a motor starter assembly

A motor starter assembly made up of sub-assemblies each formed from a circuit breaker 40 and a contactor 60 and positioned on a baseplate 20 with which a set of power bars 23 is associated. The baseplate includes a support area 21 for the sub-assemblies and a connection are preferably a bracket 22 that is overhanging in relation to the support area. The baseplate further includes power connection elements and or control connection elements provided on the bracket and the connection area to permit plugging in of the sub-assemblies on the baseplate along an engagement direction Z approximately parallel with the support area and perpendicular to a direction X of a set of bars.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an assembly of electrical equipment for the power 
control of loads, notably motor starter devices, this assembly comprising 
a baseplate and a set of power conductors provided to supply power to the 
loads, for each load, a pair of devices mounted on the baseplate and made 
up of a circuit breaker and a contactor, the pairs of devices being 
capable of being placed side by side on the baseplate. 
2. Discussion of Background 
Such an equipment assembly is used to supply power to a load such as a 
motor, in order to start it or when it is stopped according to the power 
up or power down of control conductors of the contactor; the circuit 
breaker is attached to the contactor in order to cut the power supply 
lines of the contactor when it detects, by means of suitable monitoring 
devices, an operational anomaly, for example an overcurrent in at least 
one of these lines. 
Known motor starter assemblies include baseplates fitted with a length of 
section for supporting the circuit breaker and a length of section for 
supporting the contactor; the operator must wire up the contactor with the 
circuit breaker, connect this to the set of bars and wire up the control 
conductors to the corresponding terminals of the contactor and possibly to 
a signalling auxiliary contact deck which is attached to the circuit 
breaker and which opens the control circuit in the event that the circuit 
breaker is triggered. The wiring and mounting operations which this 
involves are long and tedious. It is on the other hand desirable to be 
able to group together several contactor-circuit breaker assemblies in a 
single device, particularly when these assemblies must be connected to a 
control bus. 
SUMMARY OF THE INVENTION 
The aim of the invention is to simplify the assembly and disassembly 
operations of several pairs of devices of the contactor-circuit breaker 
type and to reduce the wiring operations for these devices, while at the 
same time facilitating their connection to the control conductors, for 
example, to a control bus. The word "control" is used here in the broad 
sense and denotes both the command of the devices in the assembly and the 
condition signalling for this equipment or the command of other pieces of 
equipment according to their condition. 
According to the invention, the baseplate comprises, on the one hand, a 
support area to receive several pairs of devices and on the other hand 
power and control pins that co-operate with the respective power and 
control terminals of the pairs of devices, and one of the devices is 
engaged with the power connection pins and the control connection pins of 
the baseplate along an engagement direction that is approximately parallel 
to the support area. 
Preferably, the pairs of devices are assembled in a unitary fashion on the 
baseplate along the aforesaid direction, by means of at least one 
associated unit equipped with a fitting device that co-operates with a 
housing provided with abutments or retaining shoulders and provided on or 
in the baseplate. 
The baseplate can comprise a bracket extending from the support area and 
overhanging in a direction perpendicular to the support area to house the 
set of power conductors and having plug-in connectors to co-operate with 
the circuit breaker or a signalling auxiliary contact deck attached to the 
circuit breaker, for each pair of devices; the baseplate can also house 
behind the support area, a printed circuit fitted, for each pair of 
devices, with tracks for the interconnection of the contactor coil with a 
control bus and corresponding connectors. 
It is advantageous that the contactor be linked to the circuit breaker by 
means of an intermediate power interconnection unit which is provided with 
a fitting device that co-operates with a corresponding fitting device 
provided on or in the baseplate and which includes, on the one hand, power 
interconnection pins between the contactor and the circuit breaker and on 
the other hand plug-in elements that co-operate with complementary 
connection elements provided on the baseplate. On the other hand, an end 
unit can be fixed under the contactor, this end unit being equipped with a 
fitting device which co-operates with a corresponding fitting device 
provided on or in the baseplate and which includes pins for 
interconnecting with the control terminals of the contactor. The fitting 
devices of the baseplate are preferably housings created in the support 
area of the baseplate in order to provide guiding, holding and abutment 
elements for the pairs of devices. An immobilisation device can be joined 
onto the intermediate or end unit linked to the pair of devices in order 
to prevent it from being displaced in a direction opposite to its 
direction of engagement.

DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring now to the drawings, wherein like reference numerals designate 
identical or corresponding parts throughout the several views, and more 
particularly to FIG. 1 thereof, there is illustrated a motor starter 
assembly according to the present invention. 
In FIG. 1, the device shown is a motor starter assembly with four units but 
it is obvious that it can include a different number of starter units, for 
example one, two or eight. Similarly, the device can be assembled and 
connected by any of the usual means to a neighbouring device. 
The motor starter assembly 10 includes a baseplate 20 on which are housed 
and connected starter sub-assemblies 30. Each sub-assembly includes a pair 
of electrical devices and two associated connection units, namely a 
circuit breaker 40, an intermediate unit 50, a contactor 60 and an end 
unit 70. The baseplate 20 can be fixed at the rear to a support by the 
usual fixing means: clip-on elements, screws, etc. 
The baseplate 20 includes a body of small depth fitted with a front support 
area 21 generally parallel to a plane P to support the sub-assemblies 30 
and to provide the interconnections between their components and, 
projecting from the body along a direction Y perpendicular to the plane P, 
an upper overhang 22 in the shape of a bracket; the baseplate houses a set 
of power supply conductors 23, for example bars, which extend along a 
general direction X parallel to P and are connected on the one hand to a 
power supply connection 23a at the side or, as shown, at the front and on 
the other hand to power connection pins 24; the bracket 22 also has 
control connection pins 25; the pins 24 and 25 extend along a direction Z 
parallel to P and perpendicular to X and Y. The baseplate 20 houses a 
printed circuit 80 which is parallel to P and provides the control 
interconnections via connectors 81,82 and the external control connection 
via the side connectors 83; the printed circuit 80 will be described 
further below. 
The circuit breaker enclosure has upstream 41 and downstream 42 terminals, 
accessible for connecting flexible or rigid conductors through the 
respective orifices 41a and 42a and with handling tools through the 
frontal orifices 41b, 42b. The circuit breaker 40 has a rear face 43 and 
jutting out towards the front, a nose 44, fitted with at least one manual 
opening/closing command button 44a. On the nose of the circuit breaker, a 
signalling auxiliary contact deck 45 is arranged, fitted with terminals 
46; the terminals 46 include access at the top 46a for the connection of 
the pins 26 and front orifices 46b for handling these terminals. 
The contactor enclosure 60 has upstream 61 and downstream 62 power 
terminals accessible for the connection of flexible or rigid conductors 
through upper orifices 61a and lower orifices 62a and with handling tools, 
onto a front face 64, through front orifices 61b,62b; the contactor 
enclosure 60 also has a rear face 63 and next to the upstream 61 and 
downstream 62 power terminals, upstream 65 and downstream 66 control 
terminals with their respective access orifices 65a,66a. Depending on the 
situation, the coil of the contactor is connected to two upstream control 
terminals or to one upstream control terminal and one downstream control 
terminal. 
The intermediate unit 50 is of small height and includes power 
interconnection conductors 51 between circuit breaker and contactor, 
terminated by pins 52 in order to co-operate with the downstream terminals 
42 of the circuit breaker 40 and by pins 53 in order to co-operate with 
the upstream terminals 61 of the contactor 60. The intermediate unit 50 
comprises, in addition, at the rear, a fitting and connecting heel 54; 
this heel is provided on the one hand with shapes 55 that can be fitted 
into a housing 26 of the baseplate in order to co-operate with a top 
abutment face 26a, side abutment faces 26b and retaining shoulders 26c 
towards the front; the heel 54 is on the other hand fitted with control 
connection elements 56 directed along Z and co-operating with the 
connector 81 arranged on the printed circuit and accessible at the bottom 
of the housing 26. The lower control pins 57 adjacent the power pins 53 
are arranged in order to connect to the upstream control terminals 65 of 
the contactor 60. 
It should be noted that the intermediate unit 50 has in its upper part, 
shapes 58 capable of been gripped by the fingers of the operator in order 
to facilitate the displacement of the sub-assembly along Z for its 
assembly and disassembly. 
The end unit 70 provides through a void 71, passage for power conductors 
intended to connect the downstream terminals 62 of the contactor 60 to the 
load; the unit 70 includes control pins 72 to be connected to the 
downstream control terminals 66 of the contactor and a fitting and 
connecting heel 73. This heel is provided on the one hand with fitting 
shapes 74 to co-operate with the shapes and walls of a housing 27 in the 
baseplate, in particular with a top abutment 27a, side abutments 27b and 
front retaining shoulders 27c. The heel 73 is, on the other hand, fitted 
with control connection elements 75 directed along Z and co-operating with 
a connector 82 provided in the bottom of the housing 27. A catch 76 
controlling the elements that clip the unit 70 into the housing 27 can, on 
the other hand, be provided at the front of the unit 70 in order to 
strengthen the immobilisation of the sub-assembly on the baseplate. 
The baseplate 20 includes, in addition to the housings 26,27 and the 
associated connectors 81,82, side housings 28 that include connectors 83 
to provide the connection for the connectors to which are connected the 
control conductors and/or command conductors 90 which provide the link 
with a process controller or form part of an area bus. Extra side housings 
29 including connectors 84 are provided for the connection of power supply 
conductors to be connected to relays provided on the printed circuit 80 
when voltage amplification is desired. 
It will be noted that the support area 21 is approximately flat, with the 
exception of the parts set back which form the housings 26-29, in such a 
way that, after insertion approximately along Y, of the heels 54,73, the 
intermediate 50 and the end unit 70, the sub-assemblies 30 can be engaged 
and connected along the direction Z parallel to the plane P of the support 
area 21, and this without any need for wiring up. The rear faces 43,63 of 
the circuit breaker and the contactor are coplanar with the rear faces of 
units 50, 70. The front face 59 of unit 50 is projecting under the nose 44 
in order to facilitate gripping the shapes 58. 
The printed circuit 80 is illustrated separately in FIG. 6 so as to show 
better its connectors 81-84. The circuit 80 provides, with the help of 
tracks 85 the desired interconnections. 
The baseplate 20 illustrated in FIG. 9 includes on the one side, lateral 
elements in relief 91 and on the other side complementary hollowed out 
elements 92, so as to assist the assembly of neighbouring baseplates. In 
FIG. 9 a variant of an elastic catch 76 can be seen provided in order to 
lock the lower unit 70 in position; actuation of the catch is carried out 
by means of a tool inserted into a channel passing through the end unit 
70. The set of power supply bars 23, the pins 24 connected to these bars 
and the internal control conductors 93 which connect the pins 25 to the 
printed circuit are moulded into bracket 22 (see FIG. 10). A pivoting flap 
94 capable of carrying labels associated with the various groups of 
devices is mounted at the front of the bracket 22 to conceal the inlets 95 
to the orifices giving access to the circuit breaker terminals 40 and/or 
its auxiliary deck 45. The control terminals mentioned are the type that 
are clamped by a screw or by an elastic component. 
The mounting of the sub-assemblies 30 onto the baseplate 20 of the device 
described is as follows. 
The user begins by assembling the contactor 60 to the circuit breaker 40 
through the intermediate unit 50 by on the one side plugging the pins 52 
into the orifices 42a of the terminals 42 of the circuit breaker and on 
the other side plugging the pins 53 and 57 into the orifices 61a, 65a of 
the terminals 61, 65 of the contactor and tightening up the screws of the 
terminals. Then he assembles the end unit 70 to the contactor by inserting 
its pins 72 into the orifices 66a of terminals 66 of the contactor and 
tightening up the screws of these terminals. To mount the sub-assembly 
thus produced onto the baseplate 20, the user then engages the heels 54, 
73 of units 50, 70 projecting from the back of the sub-assembly into the 
housings 26, 27 in the baseplate and then slides the sub-assembly in the 
direction Z along the support area 21. The sliding is carried out with 
lateral guide being provided by the walls 26b, 27b of the housings 26,27 
until the power lugs 24 are located in the terminals 41 of the circuit 
breaker and the control pins 25 in the terminals 46 of its auxiliary 
contact deck 45. The elastic catch 76 engages and ensures the sub-assembly 
is held and resists any accidental displacement in the direction Z, while 
the abutments 26b, 27b retain the sub-assembly in the direction X and the 
shoulders 26c, 27c prevent it being pulled out of the baseplate in the 
direction Y. The unit 70 can also be joined on and connected to the 
baseplate after mounting the devices 40 and 60 with their connecting unit 
50. 
As a variant, the intermediate unit 50 can first be assembled to the 
circuit breaker 40, then the circuit breaker engaged along the direction Z 
and connected to the pins 24, 25; the contactor is then engaged along Z 
and connected to the pins 53, 57 of unit 50 and the unit 70 is mounted and 
locks the assembly. 
The power connection of the assembly to a source of energy is carried out 
by the appropriate connection of conductors to the front terminal block 
23a. The control connection is carried out by the connection of individual 
cables or a cable bundle to the side connector 83. 
To disassemble a sub-assembly, the user unscrews the terminal screws 41 of 
the corresponding circuit breaker, then unlocks the catch 76 and grasps 
the shapes 58 of the intermediate unit 50 and the underneath of the end 
unit 70, and pulls the sub-assembly downwards in the direction opposite to 
Z1, this movement been limited by the abutment of the heel 54 against the 
bottom of the housing 26, and finally extracts the sub-assembly from the 
baseplate in the direction X. To simply disassemble the contactor from a 
sub-assembly it is sufficient to unscrew the terminal screws 61 of the 
contactor, then to unlock the catch 76 and continue the operation as 
above. 
It will be noted that when assembling, the wiring work which the user must 
carry out is considerably simplified since he must only initially connect 
the load to the power terminals of the contactor and the three phase power 
supply and the source of command voltage for the contactors. The addition 
of a neighbouring assembly is carried out by the side fitting of the male 
and female elements 91, 92 and the interconnection of the control 
connectors 83 and if the case arises 84 putting them facing one another 
and with power terminals adjacent 23a. 
Obviously, numerous modifications and variations of the present invention 
are possible in light of the above teachings. It is therefore to be 
understood that within the scope of the appended claims, the invention may 
be practiced otherwise than as specifically described herein.