US1361934A - Assighstor to indus - Google Patents

Description

Patented Dec.14,1 920.

2 SHEETS-SHEET I.

31367 5071 1%7772072 Z. I571 Valli'nbury H. L. VAN VALKENBURG.

MOTOR STARTER. APPLICATION FILED SEPTJ, I918.

PATENT fiFFIfiE.

IIERlVION L. VAN VALKENBURG, OF IQIL'WAUI'ZEE, WI$CQNSIN, ASSIGNOR TO INDUS- TRIAL CONTROLLER COMPANY, OF It QILI/VAUKEE, WISCONSIN, A GORPORATION OF WISCONSIN.

MOTOR-STARTER.

Specification of Letters Patent. Patgnted D 14 1920 Application filed September '7, 1918. Serial No. 253,034.

T 0 all whom it may concern Be it known that I, HERMON L. VAN VAL- KENBURG, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of IVisconsin, have in vented a certain new and useful Improvement in Motor-Starters, of which the following is a specification.

My invention relates to automatic motor starters designed to start the motor under certain conditions and continue its operation under certain other conditions. Commonly, the motor is started under the protection of a protective element which atfords the motor time to gain a speed sufficient to generate the necessary counter E. M. F; after which the protective element is cut out and the motor receives -full operating current. The protectiveelement may assume the form ofresistance, which serves to reduce the amount of current supplied to the motor at starting, or, in the case of an alternating current motor, an autotransiormer, which has the effect of reducing the voltage impressed on the motor terminals. in either of these cases the starting conditions differ from the running conditions by the interposition of a protective element. But

a protective element is not always used. In

some cases, as illustrated in my Patent No. 1,319,191, allowed April 15, .1919, it is permissible to subject the motor to full line current at starting. In such cases it is com- B10111!) protect the motor from excessive current, when running, by supplying the current through a fuse or similar device, which will blow in case the current becomes excessive. But when the motor is thrown direct on to the line when standing still,

there is an initial rush of current which would probably blow the fuse, and to avoid this. things are so arranged that in starting, the fusewill be out of circuit and in running will be in circuit. So it is common practice for the starting conditions tobe different v the running conditions. And, as is well switches may be operated manually, but this is not always convenient, and furthermore, it is not always well to give the attendant control, for there is danger that he will throw the running switch prematurely. T his has been avoided by devising automatic time limit starters which deprive the attendant of the power to vary the interval between the closing of the starting switch and the closing oi the runningswitch. The object of my invention, viewed in one important aspect, is to provide apparatus in which there is a time limit device which will render it certain that the running switch cannot be closed in less than a predetermined interval after the switch is closed and yet affords the attend ant the power to increase the length of the interval at will. Thus my apparatus makes it possible to take advantage of the human element and give the attendant the power to increase the interval if he desires, but prevents him from reducing the interval, below a permissible minimum. Another object is to provide, in an apparatus of this kind, a relay coil which when energized closes the starting switch and thereupon brings the'time limit device into action.

Another object of my invention is to provide interlocking means whereby the running switch cannot be closed unless the starting switch has been previously closed.

Another object of my invention is to provide means whereby the coil which actuates the starting switch will'be open-circuited as soon as the running switch has been closed, thus preventing waste of electric energy, and heating of the coil. v

I accomplish my objectsv in the manner illustrated in the accompanying drawings,

whichretarder.

Fig. 3 is a diagram showing a type of starter in which, when the starting switch is closed, current is supplied through a protective resistance in the motor circuit, and when the running switch is thrown to runstarting ning position the resistance is cut out and a tus substituted. This is especially adapted for polyphase, squirrel cage motors.

Fig. 1 is a diagram of a type applicable especially to polyphase slip ring motors. lhe apparatus is designed, at starting, to introduce resistance in the armature circuit.

Similar numerals refer to similar parts throughout the several views.

Referring first to tl e compensator type shown in big. 1 and the special form of time limit device shown in Fig. 2:

The conductors 1, 2 and 3 are the line, or supply conductors. T hey lead to the contacts 1, 5, 6 respectively of the running switch. Branches 7, 8, 9 lead respectively to the contacts 10, 11, 12 of the starting switch. The starting switch is shown as three pole single throw switch having arms or contactors 1e, i l, 15 adap'ed to engage the contacts 10, 11 and 12 respectively. They are connected by an insulating bar 16 so as to operate in unison, and are biased toward open position by a spring 17. They are permanently connected by conductors 20, 21 and 22 to the compensator coils 233, 2 1, 25

respectively. Said coils are interconnected in the usual manner by conductors 26, and 27. Intermediate points of said coils are connected by conductors 30, 31 and 52 respectively, to the contacts 33, 3d, 35 respectively. The switch arms or contactors 3?, 38, 39 of the running switch are adapted to engage the contacts 33, 84, 35 respectively. The switch arms or contactors l0, oi the running switch are adapted to engage the contacts 1, 5 and 6 respectively. The arms of the running switch are permanently connected by the conductors 13, a l, to the terminals of the motor M. An insulating bar at? connects the arms of the running switch so they will operate in unison and a spring 18 acts upon the bar in such manner that the arms will tend to assume pre-starting position shown in Fig. 1. It will be understood that arm 10 is rigidly connected to arm 3?, arm 41 is rigidly connected to 38, and arm s2 is rigidly connected to arm 39; and that the parts are so arranged that when the contacts 4, and 6 are engaged the contacts 3?), 841- and will be disengaged and vice versa.

The bar 16 of the starting switch is actuated by a core operated by a coil 51 which, for convenience be termed the starting coil. Gne end of this coil is connected by a conductor 52 to a stationary contact 53. The other end is connected by a conductor 5%: to stationary contact 55. A stationary contact 56 forms a companion to the contact and these are adapted to be bridged by switch or contaetor 57 of a manually controlled switch provided for stopping the motor. It is here shown symbolically as being of the normally closed,

push button type, a spring 58 normally ongaging the button 59 in such manner as to normally keep the circuit closed. The contact 56 i. connected by a conductor 60 to the conductor 61 which leads from the con tact 11. The contact 55 is connected by a conductor (53 to one of the two contacts oi and adapted to be bridged by the main controlling switch A second pair of contacts 07 and 68 are adapted to be bridged by said switch when the later is in starting position as hereinafter described. Two conductors T0 and 71 lead from the contacts 67 and 68 respectively to the contacts 72 and respectively. These latter cpntacts are adapted to be bridged by the contactor when the starting switch is in starting position. Said arm is rigidly connected to, but insulated from the arm 15 of the starting switch and he so is operated by it. Contact 73 is connected by a conductor 113 to contact 12.

The contact (35 is connected by a conductor to one end of the coil which actuates a core or plunger 82 connected to the bar 47 for operating the running switch. This may be termed the running coil. The other end of the coil is connected by a conductor 8 1 to conductor 85 which is connected to the conductor 70. Said conductor 85 connected by a conductor 86 to a contact A switch arm 90 adapted to bridge the contacts 53 and 8''? in one position and in another position to bridge the contacts 91 and 92. Arm 90 is rigidly con ne-cled to, but insulated from the arm 42 ot' the running switch and is actuated by in such manner that when the running stitch is in non-running position as shown in this diagram, the contact 53 will be in electric connection with the contact 87 and when in running position the contact 91 will be electrically connected to the contact 90. Contact 87 is connected by a conductor 94 to the contact 92 while the contact 91 is connected by a conductor 95 to the contact 6.

The main controlling switch 66 is con nected by a rod to the core or plunger 101 operated by a coil 102, which may be termed the relay coil. One end of this coil is connected by a conductor 103 to the contact 68. The other end is connected by a conductor 104 to one of a pair of con tacts 105, 106 adapted to be bridged by the contactor 107 oi? the master su 'h. This master switch is here shown as being of the momentary contact, switch button type and has a button 108 engaged by a spring 109 in such manner as to bias the switch to open position. Contact 10 is connected by a conductor 112 to the conductor 61.

It will be understood that the parts are illustrated in the diagram symbolically rather than structurally. In Fig. 1. the

main controlling switch and plunger 101 are shown as urged downward by gravity,

- although it will be understood that additional or other influences may be employed.

In the form shown, when the relay coil is energized the main controlling switch is raised into engagement with the contacts 67 and 68 and whenthe coil is deenergized the plunger and switch descend, bringing "the switch into engagement with the contaets 6 1, 65.

The downward movement of these parts is controlled by a time limit de- -vice here shown as a dash pot, see esperetarded.

In operation, under normal non-running conditions, the parts will assume the position shown in the diagram, Fig. 1. hen the attendant desires to start the motor, he presses the button 108 of the master switch, thus bridging the contacts 105, 106 and consequently energizing the relay coil 102 as follows: from line conductor 2 to conductor 8, contact 11, conductor 61, conductor 112, contact 106, switch 107,contact 105, conductor104c,coil 102, conductor 103, contact 68, conductor 71, contact 7 3, conductor 113, contact 12, conductor 9 to the other side 3 of the line. The relay coil upon thus being energized, raises the switch 66 to starting position, which causes it to bridge the contacts 67, 68 and energizes the operating coil 51 as follows: from the line conductor 2 to conductor 8, contact 11, conductor 61, conductor 60, contact 56, switch 57, contact 55, conductor 54, coil 51', conductor 52, contact 53,

' ing coil51'is energized, it moves the plunger in a direction to close the starting switch 13, '14, 15. This supplies current to the motor as "follows: from the line conductor 1 to conductor 7, contact 10, switch arm 13, conductor 20, part of the coil 23 of the autotransformer, conductor 30, contact 33, switch arm 37, conductor 13 to one of the motor terminals, thence from another motor terminal. to the conductor 44, switch arm 38, contact 34, conductor 31, part of the coil 21 of theautotransformer, conductor 21, switch arm 14, contact 11, and conductor 8 to the opposite side 2 of the line. In a similar manner, the other motor terminals are connected with the conductors 2 and 3 of the line. As long as the attendant keeps the master switch closed no change will occur in the switch connections and the motor will continue to gather speed until it reaches the maximum speed attainable so long as the motor is being fed through the autotransformer. In any event, the attendant has the option of either keeping the master switch closed and the running switch in starting position, or he may release and thus open the master switch, and thus deenergize the relay coil 102 and permit the switch 66 to descend and bridge the contacts 6 1, 65. Thus the attendant has the option of either delaying the commencement of operation of the time limit device, or of permitting it to function immediately.

When the switch 66 reaches final position bridging the contacts 61, the running coil 81 will be energized as follows: from the line conductor 2 to conductor 8, contact 11, conductor 61, conductor 60, contact 56, switch 57, contact 55, conductor 63, contact 6 1, main controlling switch 66, contact 65, conductor 80, coil 81, conductor 81, conductoi 85, conductor 70, contact 72, interlocking switch 7 4, contact 73, conductor 113, contact 12, conductor 9, to the opposite side 3 of the line. The energization of the coil 81 moves the plunger 82 in a direction to throw the running switch from starting to running position, which causes it to disengage the contact 33, 31, and engage the contacts 1, 5 and 6, thus opening the circuit through the autotransformer and connecting the motor direct to the line conductors 1, 2, 3. This movement of the starting switch moves the auxiliary switch 90 away from the contacts 53, 87 and into engagement with the contacts 91, 92, thus breaking the circuit through the starting coil 51-and permitting the starting switch to move to normal non-running (or pre-starting) position, shown in the diagram. This, however, does not break the circuit through the running switch coil 81 which will now be energized as follows: from the line condutcor 2 to conductor 8, contact 11, conductor 61, conductor 60, contact 56, switch 57, contact 55, conductor 63, contact 64, switch 66, contact 65, conductor 80, coil 81, conductor 8 1, conductor 86, contact 87, conductor 94:, contact 92, auxiliary switch 90, contact 91, conductor 95, contact 6, to the opposite side 3 of the line. Thus, as soon as the running switch reaches running position coil 51 will be denergized, thus avoiding waste of energy, and the danger of heating the coil. The parts will maintain these positions until the attendant desires to stop the motor, which he may do a any time by pressing the stop button 59, and

thus disengaging the stop switch 57 from the con ts 55, 56. This breaks the circuit through the running coil 81 and permits the spring 18 to move the running switch to the position shown in Fig. 1, thus breaking the connection between the supply lines 1, 2, 3 and the motor terminal conductors 43, @1 1, 15.

The form shown in Fig. 3 is analogous as to its principal parts, and is adapted for polypha-se, squirrel cage motors, The apparatus is so arranged that when the starting switch is closed current is supplied to the motor through resistances 150, 151 and 152. Upon the throwing of the running switch from starting position to running position the switch arms a l), 511, will engage the contacts 4, 5, 6 and short circuit said resistances while the arms 37, 38, 39 will disengage the contacts 33, 3 1, 35 and supply the motor through the fuses 155, 156 and 157. Consequently, current is first supplied through a protective resistance instead of a voltage reducer, as in the first instance, and the current is afterward supplied through 'luses.

The form shown in Fig. 4 is also analogous, this type being adapted for a polyphase slip ring motor. In this form the motor has a slip ring commutator 180. The three conductors 181, 182, 183 have resistances 184:, 185, 186 respectively which are star connected. In this case the running s *itch is single throw, double pole, having two arms 190, 191 adapted to engage contacts 192, 193 respectively. These contacts connected by conductors 191-. 19)?) respectively to conductor 182, while switch arm a) is connected by conductor to 001,511}?- tor 181 while switch arm 191 is 'mnectcd by conductor 196 to conductr 183. The running switch is normally open, thus leaving the protective resistances 18 1, 185, 186 in circuit. As soon as the coil 81 is energized and the running switch is closed the resistances 184, 185, 186 will be short circuited.

It will be evident that in eachv form the motor has the advantage of a protective element in starting which is afterward cut out of circuit automatically. It will also be noted that the attendant by pressing the start button 108 will energize the relay coil 102 which accomplishes two things. First, it will cause the starting switch to be thrown to starting position, and second, it will set the time limit device so that as soon as the start button is released the time limit device will be brought into action and will introduce a time interval before the running switch is thrown to running position.

Having thus described my invention what I claim as new and desire to secure by Letters Pater. is

1. The combination, with a motor, of a starting switch, a running switch, separate actuating means for operating the respective switches, and timing means for said actuating means comprising a manually controlled device having a handle adapted to occupy two positions, said manually controlled devcc being adapted, when the handle is in one position, to cause the operation of the means which actuates the starting switch, and a mechanically controlled device having a time limit characteristic and adapted, when in final position, to cause the operation of the means which actuate the running switch, the manually controlled device being adapted when moved to its other position to initiate the time limiting action of said mechanically controlled device.

2. The combination, with a motor, of a starting switch, a running switch, a first coil, for operating said starting switch, a second coil, for operating said running switch, a main controlling switch for controlling the energization of said coils, said main controlling switch, when in starting position, causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, said main controlling switch being biased toward running position, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for moving said main controlling switch to starting position, and simulneously setting said time limit device, and a araster switch for controlling the energization of said relay coil.

The combination, with a motor, of a 'ing switch, a running switch, a first coil. for operating said starting switch, a second coil, for operating said running switch, a main controlling switch for controlling the energization of said coils, said main controlling switch, when in starting position, causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, an interlocking switch located in the circuit of the second coil and operated by the starting switch, whereby the second coil cannot become effective and hence the running switch cannot be closed unless the starting switch is first closed, and means for operating said main controlling switch.

1. The combination, with a motor, of a starting switch, a running switch, a first coil, for operating said starting switch, a second coil, for operating said running (c-h, a main controlling switch for con- Ll'C-lllllg the energization of said coils, said maincontrolling switch, when in starting position, causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, an interlocking switch located in the circuit of the second coil and operated by the starting switch, whereby the second coil cannot become effective and hence the running switch cannot be closed unless the starting switch is first closed, and means for operating said main controlling switch, including winding for moving said switch to starting position against its bias, a master switch for controlling the energization of said winding and a time limit device for retarding the movement of said main controlling switch to running position.

5. The combination, with a motor, of a starting switch, a running switch, a first coil, for operating said starting switch, a second coil, for operating said running switch, a main controlling switch for controlling the energization of said coils, said main controlling switch, when in starting position, causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, an interlocking switch located in the circuit of the second coil and operated by the starting switch, whereby the second coil cannot become effective and hence the running switch cannot be closed unless the starting switch is first closed, and means for operating said main controlling switch, said means having both a manually controlled device and a time limit device for jointly determining the interval taken by the main controlling switch in moving from starting position to running position.

6. The combination, with a motor, of a starting switch, a running switch, a first coil, for operating said starting switch, a second coil for operating said running switch, a main controlling switch for controlling the energization of said coils, said main controlling switch, when in starting position, causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, an interlocking switch located in the circuit of the second coil and operated by the StZIItlII SWltCh, whereby the second coil cannot become effective and hence the running switch cannot be closed unless the starting switch is first closed, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for controlling said main controlling switch subject to the action of the time limit device, and a master switch for controlling the energization of said relay coil.

7. The combination, with a motor, of a starting switch, a running switch, a first coil, for operating said starting switch, a second coil, for operating said running switch, a main controlling switch for controlling the energization of said coils, said main controlling switch when in starting position causing said first coil to operate the starting switch and when in running position causing the second coil to operate the running switch, an auxiliary switch located in the circuit of the first coil and operated by the running switch whereby the first coil is rendered ineffective as soon as the running switch is closed, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for controlling said main controlling switch subject to the action of the time limit device, and a master switch for controlling the energization of said relay coil.

8. The combination, with a motor, of a starting switch biased to open, a running switch biased to open, a first coil adapted when energized to close the starting switch, a second coil adapted when energized to close the running switch, a main controlling switch adapted when in starting position to energize the first coil, and when in running position to energize the second c011, sald main controlling switch being biased toward running position, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for moving said main controlling switch to starting position and simultaneously setting said time limit device, and a master switch for controlling the energization of said relay coil.

9. The combination, with a motor, of a starting switch biased to open, arunning switch biased to open, a first coil adapted when energized to close the starting switch, a second coil adapted when energized to close the running switch, a main controlling switch adapted when in starting position to energize the first coil, and when in running position to energize" the second coil, said main controlling switch being biased toward running position, a dash pot for retarding the movement of the main controlling switch from starting position to running position, a relay coil which when energized, moves the main controlling switch to starting position and simultaneously resets the dash pot to operate as a retarding device, and a normally opened master switch adapted when closed to energize said relay coil.

10. An automatic motor starter comprising a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position in which the motor is connected to the transformer and disconnected from the line and a running position in which the motor is connected to the line and disconnected from the transformer, separate actuating means for actuating said switches, and controlling means for rendering said actuating means effective successively, whereby first the starting switch is closed and then the running switch is moved to running position, said controlling means having a time controlled element and a manually controlled element for jointly determining the interval between the time when the means for actuating the starting switch becomes effective and the time when the actuating means for the running switch moves the running switch from starting position to running position.

11. An automatic motor starter comprising a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position in which the motor is connected to the transformer and disconnected from the line and a running position in which the motor is connected to the line and disconnected from the transformer, separate actuating means for actuating said switches, and controlling means for rendering said actuating means effective successively, whereby first the starting switch is closed and. then the running switch is moved to running position, said controlling means having a manually controlled element and a time controlled element, the manually controlled element being capable of occupying two positions, in one position rendering effective the means for closing the starting switch, and simultaneously setting the time controlled element, the time controlled element being adapted to thereafter delay the moving of the running switch to running position after the starting switch is closed, said manually controlled element being adapted when in its other position, to release said time controlled element and permit it to function.

12. An automatic motor starter comprising a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position in which the motor 'is connected to the transformer and disconnected from the line and a running position in which the motor is connected to the line and disconnected from the transformer, a first coil for closing the starting switch, a second coil for moving the running switch from starting position to running position, a main controlling switch for controlling the energization of said coils, said main controlling switch when in starting position causing the first coil to close the starting switch and when in running position causing the second coil to move the running switch from starting position to running position, a time limit device for retarding the movement of the main controlling switch from starting to running position, a relay coil for controlling said main controlling switch, subject to the action of the time limit device, and a master switch for controlling the energization of said relay coil.

13. An automatic motor starter comprising a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position in which the motor is connected to the transformer and disconnected from the line and a running position in which the motor is connected to the line and disconnected from the transformer, a first coil for closing the starting switch, a second coil for moving the running switch from starting to running position, a main controlling switch for controlling energization of said coils, sald main controlling switch when in starting positlon causing the first coil to close the starting switch, and when in running position causing the second coil to move the running switch from starting position to running position, said main controlling switch being biased toward runnin position, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for moving said main controlling switch to starting position, and simultaneously setting said time limit device, and a master switch for controlling the energization of said relay coil.

14. An automatic motor starter comprising a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position in which the motor is connected to the transformer and disconnected from the line, and a running position in which the motor is connected to the line and disconnected from the transformer, a first coil for closing the starting switch, a second coil for moving the running switch from starting position to running position, a main controlling switch for controlling the cnergization of said coils, said main controlling switch when in starting position causing the first coil to close the starting switch, and when in running position causing the second coil to move the running switch from starting position to running position, said main controlling switch being biased toward running position, a time limit device for retarding the movement of the main controlling switch from starting position to running position, a relay coil for moving said main controlling switch to starting posi tion, and simultaneously setting said time limit device, and a master switch which in one position renders the relay coil effective for moving said main controlling switch to starting position and setting the time limit device, said master switch when in the other position rendering the relay coil ineffective, thereby releasing the time limit device, whereby the time limit device functions after the operator has moved the master switch to the last mentioned position.

15. The combination, with the alternating current motor, of a transformer, a starting switch for connecting the transformer to the line, a running switch having a starting position, in which the motor is connected to the transformer and disconnected from the line, and a running position in which the motor is connected to the line and disconnected from the transformer, a normally open master switch, and electromagnetic means controlled by said master switch for closing the starting switch when the master switch is closed and moving the running switch to runningposition after a predetermined interval after the master switch is opened.

16. The combination with the alternating current motor, of a transforn'ier, a star ing switch for connecting the transformer to the line, a running switch having a starting position, in which the motor is connected tothe transformer and disconnected from the line, and a running position in which the motor is connected to the line and dis connected from the transformer, a normally open master switch, and electromagnetic means controlled by said master switch for closing the starting switch when the master switch is closed, then moving the running switch to running position after a predetermined interval after the master switch is opened and finally closing the starting switch.

17. The combination, with a motor and a protective element therefor, of a starting switch, a running switch adapted to occupy a starting position in which the motor is connected to said protective element and a running position in which the motor is connected to the line and disconnected from said protective element, a first coil for closing the starting switch, a second coil for moving the running switch from starting position to running position, a main controlling switch for controlling the energization of said coils, said main controlling switch when in starting position causing the first coil to close the starting switch, and when in running position causing the second coil to move the running switch from starting position to running position, a time limit device for retarding the movement of the main controlling switch from starting to running position, a relay coil for controlling said main controlling switch, subject to the action of the time limit device, and a master switch for controlling the energization of said relay coil.

18. The combination with a motor, of a starting switch, a running switch, an electromagnetic coil for throwing the starting switch to starting position, means for throwing the running switch to running position, a time limit device for regulating the opera tion of said means, and a relay coil adapted, when energized, to cause said electromagnetic coil to throw the starting switch to starting position and to set said time limit device.

19. The combination with a motor, of a starting switch, a running switch, an electromagnetic coil for throwing the starting switch to starting position, means for throwing the running switch to running position, a time limit device for regulating the operation of said means, a relay coil adapted, when energized, to set said time limit device and when de e'nergized to release it to permit it to perform its function, and a master switch for controlling the circuit of said relay coil, said relay coil, when energized being adapted to cause said electromagnetic coil to throw the starting switch to starting position. In witness whereof, I have hereunto subscribed my name.

HERMON L. VAN VALKENBURG.

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