US1295498A - System of electrical distribution. - Google Patents

Description

E. M. HEWLETT (Ia C. I. BURKHOLDER.

SYSTEM OF ELECTRICAL DISTRIBUTION.

APPLICATION FILED MAR. 9. I9I7. v

Patented Feb. 25, 1919.

2 SHEETS-SHEEI I.

- Inventor s Charles LBurkhoIder.

I Edward MI-Iewlett,

b5 Their Attorney.

E. M. HEWLETT & c. I. BURKHOLDIER.

SYSTEM OF ELECTRICAL DISTRIBUTION.

APPLICATION FILED MAR. 9,19I7.

1,295,498. Patented Feb. 25, 1919.

2 SHEETS-SHEET 2.

I Fig. 2.

lri ventor s Charles LBurkholder: Edward M .I-lewletc b MQ Their Attorney.

UNITED STATES PATENT OFFICE.

EDWARD M. HEWLETT, OF SCHENECTADY, NEW YORK, AND CHARLES I. BURKHOLD ER, 01' CHARLOTTE, NORTH CAROLINA, ASSIGNORS T0 GENERAL ELECTRIC .COMIANY,

A CORPORATION OF NEW YORK.

' Specification of Letters Patent.

SYSTEM OF ELECTRICAL DISTRIBUTION.

Patented Feb. 25, 1919.

Application filed March 9, 1917. Serial No. 153,750.

To all whom it may concern: 1

Be it known that we, EDWARD M. HEWLETT and CHARLES I. BURKHOLDER, citizens of the United. States, residing, respectively, at Schenectady, county of Sch'ene'ctady, State of New York, and at Charlotte, coimty of Mecklenburg, State of North Carolina, have invented certain new and useful Improvements in Systems of Electrical Distribution, of which the following is a specification.

Our invention relates to systems 'of'elec-' trical distribution and particularly to controlling means for the circuits of a plurality fof electric conductors-orv feeders of such' systems:

When it is desired feeders in predetermined time interva1s,'1t

has been the usual practice to provide eachof the protective relays controlling, the independent trip circuits for the feederswith separate timing means, whereby their time of operation could be regulated. It has been found, however, that when'it is essential that a plurality of feeders be opened in a predetermined sequence that the" independent timing devices cannot be relied upon, as duean abnormal condition on its feeder sets the common timing device into operation and as long as the relay isactuated, the common device is'operated until, after a predetermined time, it completes thetrip circuit of the relay actuated, to open its corresponding feeder. The time interval between the oc-' currence of the abnormal condition and the opening of the corresponding feeder is therefore controlled by adevice in comm on to all. thetrip circuits for the feeders and there is no danger that any feeder will be opened before its time interval and due to the operation of the common timing device the sequence of opening the feeders is alto open a plurality of ways certain. Means is also provided for at Wlll changing the time interval for tripping esired.

The novel features which we believe to be characteristic of our invention will be definitely indicated in the claims appended hereto while the features of construction and mode of operation will be best understood by reference to the following description, taken in connection with the accompanying drawings which show the'preferred embodiment of our invention and in which the fig ures show, diagrammatically, our novel control means with connections:coutrolling the circuits of a plurality of feeders. V 1

In Fig. 1 we have shown our novel" and improved control means as comprising a dial switch .having. a movable contact armor member 1 cooperating with two sets of fixed contact members 2 and 3, the contact member 1' being mounted for rotative movement on a shaft 4, and the two'sets of contact members 2 and 3 being concentrically arranged about the shaft 4 in the .path of 'travel of contact member 1. Concentri-. cally arranged also about the shaft L is contact member or ring 6 to which the contact arm is operatively connected or maintained in engagement by any suitable resilient conducting means. and the contact arm 1 are actuated or ro-i tated by means of a motor 7 through a mag-J netic clutch-8 and worm reduction gearing 9, the reduction gearing being so related to the speed of revolution ofthe motor that the contact arm engages the'sets of'contacts 2 and 3 in predetermined successive time intervals, or periods of time,-the contacts 2' being arranged to be engaged justprior to the engagement of the corresponding contacts.

The contact arm 1 is biased to initial position by a spring 10.

The two concentric sets of contact members 2 and 3 comprise an equal number-of contacts, the inner set of contacts 2 being known as bell contacts and the outer set'of contacts 3 as the trip contacts. In Fig. l we have shown our timing device as adapted to control the circuits of eleven feeders but we The shaft 4 p 20, 21 and 22 respectively which are in independent trip circuits controlled by their respective electroresponsive devices or protective relays 23, 24, 25, 26 respectively, the connections of the relay windings to their respective feeders being omit ed for purbut, by way of example, we have shown poses of clearness.

-It is understood that' the protective relays may be responsive to any predetermined abnormal condition on their feeders these relays as of the instantaneous overload type. In Fig. 1 we have shown each independent trip circuit corresponding to the feeders as connected to one of the fixed or trip contacts 3 all the trip circuits being thus controlled by the common control means or timing device.

Each trip circuit is also controlled by its.

respective protective relay, operating to close their contacts 27 and 28 in their re-' spective trip circuit. Each relay, in operating, also engages a third contact 29 which cooperates with contact 27 to control the circuitof the motor 7 and magnetic clutch. 8

"in parallel. The contacts 27 and 29 for tion.

each relay being in parallel and connected to the control buses- 30 and 31, it is evident that the actuation of any relay to close its contacts 27 and 29 setsthe motor. in opera- Operatively related to the shaft 4 and preferablycarried thereon is a cam member 32 Which cooperates with a control device for the motor circuit. This control device i. consists of a switch member 33 normally in engagement with a contact 34 to close the control circuit of the motor 7 but movable by the" cam member 32 when the contact arm 1 completes one revolution or reaches the end of its path of movement, to break engagement 'With contact 34 and open the motor control circuit and to engage contact 35 to close an indicating or alarm circuitn' The switch member 33 then remains w in position to hold the motor circuit open until reset in motor operating position by hand.

w The operation of our control means or timing device may be described as follows:

Under normal conditions on each feeder the timing device, protective relays and switches are in the posit1on indicated in Fig. 1. Let

us assume a predetermined abnormal condition, such as an overload, occurs on feeder 12, for instance. Its electroresponsive device or protective relay 24 instantly operates in response to the predetermined condition and moves into contact closing position to close simultaneously, its three contacts 27, 28 and 29. A motor operating or control circuit is then completed from the positive source of current through the switch 36 along conductors 37 to switch 33, contact 34, conductor 38, through the clutch 8 and motor 7 in parallel and then by conductor 39 to the control bus 30 and thence by conductor 40 to contacts 29 and 27 of relay 24, now closed by the actuation of the relay, to the control bus 31 and thence by conductor 36 to the negative source of current. The closing of this circuit by the actuation of the relay 24 sets the motor 7 into operation through its magnetic clutch 8 and the shaft 4 is rotated in the direction of the arrow. tensioning spring 10. It is apparent that as the contacts 27 and 29 of each relay are in parallel that the movement of any of the protective relays to contact closing position will close the motor control circuit and set the timing device into operation. Irrespective of which relay sets the timing device into operation, the contact arm 1 rotates in the direction of the arrow, engaging the cor responding contacts in each concentric set" of contacts 2 and 3 corresponding to the feeders.

As the contact arm 1 is actuated, the first movement of the timing device is to cause the contact arm to engage contacts 41 and 42. The trip circuit of feeder 11 is open at its contacts 27 and 28, as normal conditions exist on the feeder 11 and its relay 23 is in normal or contact opening position, conse quently nothing happens by the engagement of trip contact 41 but the engagement of'the bell contact 42 corresponding to feeder 11.

completes an indicating or alarm circuit from the positive source of current, throughswitch 36 along conductor 45 to contact ring 6, contact arm 1, contact 42, to the indicating device or bell alarm 46, to the control bus 31 and back over conductor 36 to the negative source of current. Indicating device or bell alarm 46 thereupon operates and gives asignal. The contact arm' 1 being still maintained in operation by the motor- 7, continues in its path of movement, breaks engagement with contacts 41 and 42 and next engages simultaneously contacts 43 and 44 corresponding to feeder'12. As contacts 42 and 44 and the other contacts in the concentric set of bell contacts 2 are connected in parallel, the engagement of the arm land contact 44 closes the bell alarm circuit again in the manner just described. With the engagement of contact 43, however, the tim-' contact closing position in the tripcircuit corresponding to the faulty feeder 12 Whose relay 24: is in contact closing position due to abnormal conditions on its feeder. In this position of the contact arm, the tripping circuitfor the feeder is therefore completed from the positive source of current along conductor 45, contact ring 6, contact arm 1, contact 43, trip coil 20, contacts 27 and 28' of relay 24, now in contact engaging position, to the control bus 31 and back over conductor 36*- to the negative source of cur-1 rent. The trip circuit for feeder 12 being completed, its trip coil 20 is energized and switch 16 automatically opened to discon nect the feeder.

Upon opening the feeder, its relay 24: is deenergized and contacts 27 and 28 opened and at the same time contact 29 is disengaged which with cooperating contacts 27 opensthe motor control circuit whereupon the motor-7 is interrupted and its clutch 8 is disconnected. Shaft 4: with contact arm 1 is then rotated in the reverse direction and returns to its initial position under the action of the resetting means or spring 10. It" is thus apparent that in response to a predetermined abnormal condition, such as an overload, upon the feeder 12, its relay 24 is operated to set in operation the timing device which after a predetermined time corresponding to the time required for the contact arm to move from initial position into position to engage contact 43, the trip circuit for feeder 12 is completed and the feeder opened. Ina similar manner our common timing device is adapted to be set into operation in response to the actuation of any of the protective relays and the contact arm 1 thereof carried successively into a circuit closing position in each trip circuit in a definite sequence until the trip circuit is reached whose relay has operated when this trip circuit is closed and its corresponding feeder opened. As-

the movement of the timing device through its contact arm 1 into circuit closing position in each trip circuit is indicated by the alarm bell, an attendant by knowing the sequence of tripping the feeders, may

merely count the number of times the bell strikes to ascertain which feeder is in opened when its feeder circuit is opened,

the motor control circuit remains c-losedand the contact arm 1 continues to successively engage the remaining set of contacts. Under such circumstances, when the contact arm completes one revolution or" reaches into engagement with the contact 35. This device thereby interrupts the motor control circuit, which circuit cannot again be closed until the control switch 33 isreset by. hand. At the same time that the motor control circuitis opened, the contact arm 1 engages the latching means or catch 35*. and is thereby held locked or restrained from returning to its initial position until the catch isreleased by hand. The engagement of the contact 35 by the switch 33 closes an alarm circuit from the positive source of current along conductor 37, to switch 33, through contact 35, to alarm device 47, and the control bus 31 back to the negative source of current. The alarm 47 rings continuously to notify the operator of the trouble.

From the connections shown in Fig. 1, the trip circuit for each feeder is operatively related to one of the trip contacts 3 so that the trip circuits are closed in a definite sequence and in predetermined successive time intervals. It is often, desirable to change the sequence of tripping and to enable each feeder tripping circuit to be closed in various time intervals. In order to adjust the time of tripping, we provide as shown in Fig. 2, means whereby the time interval for tripping each feeder may be varied at will.

In Fig. 2 we have, for purposes of clearness, shown only a portion of our control device-0f Fig. 1. Between the series of trip contacts 3 and the protective relays corresponding to each feeder we provide a time calibrating or regulating means consisting of a dial switch corresponding to each feeder having rotatably movable contact members or arms 48 cooperating with a series of concentrically arranged fixed contacts 49, the numberof fixed contacts 49 corresponding to the number of different time settings. In Fig. 2 we have shown, due to ;lack of space, the time adjusting or calibrating means applied to but four feeders as in Fig. 1 but it is understood that similar means are provided for each feeder of the plurality controlled. We have also shown, for purposes of illustration, each time setting means as comprising nine contacts t9 corresponding to nine time settings for each feeder. The similar contacts of each set of contacts 4:9 for each time setting device are connected to common buses 50, 51, 52, 53, 54., 55, 56, 57 and'58, respectively, by means of the conductors 59 and each of the common buses 50 to 58 inclusive are (in turn connected by conductors 60 to the contacts 3. 'The buses 50 and 58 inclusive comprise the common time interval buses for the plurality of feeders and correspond to successive time intervals, for instance, any feeder having its trip coil circuit connected to bus 50 will be closed, for instance, in one second and all feeders to :be tripped in two seconds will be connected to bus 51 et cetera. The time intervals represented by each bus 50 to 58 inclusive is determined by the time required for the switch arm 1' to engage the contacts 3 corresponding to the buses.

1 To more clearly describe our invention let us assume that feeders 14, 13, 12 and 11 are desired to be tripped in one, two, three and four seconds respectively. The time control means or dial switch for feeder 14 is set by moving the arm 48 to engage the first or one second contact as shown. Trip coil 22 for feeder 14 is therefore connected to bus 50 or the one second bus. The arm 48 of the dial switch for feeder 13 is moved to engage the second contact as shown, which connects the trip coil 21 to bus 51 or the two second bus. In like manner the arms 48 of the dial switches are moved to connect the trip coils 20 and 19 of feeders 12 and 11 respectively to the three and four second buses 52 and 53 respectively.

- With these time settings for opening the circuits of the various feeders, let us assume an overload occurs on feeder 13, for instance, causing its relay 25 to operate which as before described, starts the motor 7 into operation and closes its contacts 27 and 28 in the circuit of its trip coil 21. The motor 7 rotates the shaft 4 and arm 1 first engages contacts 41 and 42 and, as before, causes the bell alarm 46 to operate. The engagement of arm 1 and contact 41 fails to cause any operation as the trip circuit of feeder 14 connected to bus 50 and contact 41 is open at the contacts 27 and 28 of its relay 26. At the next successive time interval contacts 43 and 44 are engaged and, for the same reasons as just stated, the trip circuit of feeder 13 connected to bus 51 and contact 43 is not closed but the bell alarm 46 is again operated. At the succeeding time interval, which we will assume is three second after initial operation, the contact arm 1 engages contacts 61 and 62 to operate bell alarm 46 and this time a circuit is completed from the positive source of current along conductor 45 to contact ring 6, contact arm 1, contact 61, along its conductor 60, to the three-second bus 52, thence along bus 52, to the conductor 59 corresponding to the time control switch for feeder 12, to contact 63, its contact arm 48 and thence to trip coil 20, through contacts 28 and 27 closed by relay 24, to the control bus 31 and back to the negative source of current. Feeder 12 is thereby opened and relay 24 deenergized to open contacts 27 and 28 and to simultaneously break engagement with contact 29 to openthe current of motor 7. The contact arm 1 is thereupon returned to initial position as before described.

In like manner, the time required for each feeder to be opened can be determined by the setting of their contact members 48 of their respective time adjusting means and the rotatable switch arm 1 of the main control device operates to close the trip circuit of the feeder in the time desired, that is, at the end of the first time interval, the switch arm 1 of the timing device energizes the first time interval bus 50 and all trip circuits connected to this bus will be operated whose protective relays have assumed circuit closing position. At the end of the second time interval, the second time interval bus 51 will be energized and so on until that bus is energized corresponding to the time setting of the feeder at fault whereupon the feeder is opened and the apparatus returned to normal position. It is thus apparent that we provide a common timing device for all circuits and means whereby the sequence and time of tripping of each feeder may be adjusted at will.

In accordance with the provisions of the patent statutes, we have described the principle of operation of our invention, together with the apparatus which we now consider to represent the best embodiment thereof; but we desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

What we claim as new and desire to secure by Letters Patent of the United States, is

1. The combination with a plurality of circuits opened at more than one point, means for closing each of said circuits at one point in response to predetermined abnormal conditions, and means in common to all said circuits operative in response to the actuation of any of said first mentioned means for completing those circuits closed by said first mentioned means in certain ime intervals.

2. The combination with a plurality of trip circuits open at more than one point, an electroresponsive device for closing each of said circuits at one point in response to predetermined abnormal conditions, and means in common to all said circuits and opera tive in response to the actuation of any of said electroresponsive devices for completing those circuits closed by said devices in any desired sequence.

3. The combination with a plurality of trip circuits, of control means for said trip circuits comprising an electroresponsive device for each circuit, a device in common to all said circuits, and means for operating said common device in response to the actuation of any of said electroresponsive devices, said common device operating as long as any of said electroresponsive devices are actuated to assume a circuit closing position in said trip circuits until that circuit is reached corresponding to the electroresponsive device actuated.

4. The combination with a plurality of circuit opening devices, of feeders controlled means for closing the second set of contacts in each trip circuit in a certain sequence, and a control c rcult for said common'means controlled by the actuation of any of said electroresponsive means. i

5. The-combination with a plurality of electroresponsive devices, separate trip circuits controlledthereby,;of a common control means for said trip circuits set into operation by the actuation of any of said electroresponsive devices, including means formoving said control means into circuit closing relation with said 'trip circuits 'in successive time intervals, circuit controlling devices operatively related to said'trlp cir- ,cuits, each circuit controlling device being actuated only when its respective trip circuit is closed by both its respective electroresponsive device and said common control means.

6. The combination with a plurality of feeders, switches controlling said feeders,

trip circuits controlling said switches, electroresponsive devices responsive to conditions on sald feeders for controlling said trip'circuits, and a common timing means set into operation andcontrolled by the actuation 0 any of said electroresponsive devices forcompleting said trip circuits in a certain sequence. I

7 The combination with a plurality of feeders, circuit opening means for said feeders, trip circuits forsaid circuit opening means, electroresponsive devices actuatable in response to certain conditions on each of said feeders for partially 'closin-g said trip circuits, and means'operative by the actuation of any of said electroresponsive devices for. completing in a certain sequence those trip circults correspondlng to the actuated electroresponsive devices.

8. The combination with a plurality :of

.Itri circuits, a plurality of feeders contr'o led thereby, of relays controlling each circuit in response to predetermined abnormal condit ons on their respective feeders, and'a common means controlled by the actuation of any of said relays for successively assuming a circuit closing position in said trip circuits until that circuit is reached whose relay is actuated, switches for said feeders adapted to open when their trip circuits are closed by both said common means and their respective relays, and means for returning said common means to its initial position when the feeder at fault is opened.

9. The combination with a plurality of feeders, automatic circuit opening devices therefor, and trip circuits for said devices, of means for completing said trip circuits in response to abnormal conditions on their respective feeders in a certain sequence comprising, a device in common to all said trip circuits operative to successively assume a circuit completing position in said trip circuits, separate control means for each trip circuit cooperating with said device and operative to permit said device to complete only those trip circuits corresponding to feeders uponwhich abnormal conditions trip circuits, contacts in said trip circuits,

electroresponsive means controlling said contacts of each trip circuit, a device operatively related to all said trip circuits and controlled in response to the actuation of any of said electroresponsive means, second contacts in each of said trip circuits controlled in a certain sequence by said control device, only those trip circuits being rendered operative which have their first mentioned and second contacts both closed at the same time.

12. A timing device for a plurality of circuits comprising a first set of contacts operatively related to said circuits, a second set of contacts corresponding with said first set of contacts, a contact member successively engageable with similar contacts in said first and second sets, motive means for causing the engagement of said contact member and each pair of similar contacts in a certain sequence, indicating means actuated by the engagement of said arm and said second set of contacts, the engagement of said contact-arm'and said first set of contacts actingto control said plurality of circuits.

13. A timing device for a plurality of circontacts.

contacts, a similar set of indicating contacts, a cooperating contact member, motive means for causing similar contacts of each of said sets to be simultaneously and successively engaged by said cooperating contact member, means for disconnecting said motive means under predetermined conditions, a resetting means for returning said contact arm to initial position when released from said motive means, and means operative upon the completion by said contact arm of its path of movement for interrupting said motive means and locking said contact arm against its return to initial position.

14. A device for controlling the inclependent trip circuits for a plurality of feeders comprising a contact member, contacts corresponding to each of said trip circuits, actuating means operative in response to a predetermined abnormal condition on any feeder for producing a relative movement of said contact member and said contacts, said actuating means causing the engagement of said contact member and said contacts to close said trip circuits in a certain sequence, and means in operative relation to each trip circuit for rendering effective the engagement of said contact member and only those contacts corresponding to feeders having abnormal conditions thereon.

15'. A device for controlling a plurality of tripping circuits for a plurality of feeders comprising circuit opening devices for each feeder controlled by said trip circuits, relays movable in response to predetermined abnormal conditions on their respective feeders for partially closing their respective trip circuits, a control device operatively related to all said trip circuits, including means for moving said device to complete those circuits partially closed by said relays in a certain sequence.

16. The combination with a pluralityof feeders, means controlling the circuits of said feeders comprising a plurality of contacts, a member operative in response to predetermined abnormal conditionson any of said feeders for engaging said contacts in certain time intervals, control circuits for said feeders opened at two points and controlled by the engagement of said contacts, each circuit being closed at one point in response to abnormal conditions on its respective feeder and closed at the other point by the engagement of said member and said contacts, and means for rendering the completion of each circuit in response to the engagement of said member \v1th any of said 17. The combination with a plurality of said circuits in a certain sequence, and means operatively related to each trip circuit for regulating the sequence of its completion.

18. The combination with a plurality of circuits, separate control means for each circuit operative to assume circuit closing position in its respective circuit in response to predetermined conditions, a common timing device operative upon the actuation of any of said control means to assume a circuit closing position in said circuits in a predetermined sequence, and means whereby the sequence of closing of each circuit can be varied at will.

19. The combination with a plurality of feeders, trip circuits therefor, of electroresponsive means responsive to abnormal conditions on each feeder for partially closing said trip circuits, a common control means set into operation in response to the closure of any of said electroresponsive means for completing said trip circuits in a certain sequence, said electroresponsive means acting to permit the completion of only those trip circuits corresponding to feeders having abnormal conditions thereon, and means associated with said trip circuits for varying their sequence of tripping.

20. The combination with a plurality of conductors adapted to be energized in a certain sequence, a plurality of circuits, electro-responsive means for each circuit operative in response to predetermined abnormal conditions to assume a circuit closing position in its respective circuit, and means for at will connecting each of said circuits to any one of said conductors whereby said circuits are completed in any sequence desired.

21. The combination with a plurality of feeders independent trip circuits therefor, of electro-responsivemeans responsive to abnormal conditions on each feeder for controlling said trip circuit-s, a plurality of conductors successively energized in a certain sequence, time controlling means set into operation in response to the operation of any of the electroresponsive means to energize said conductors, and means for rendering each trip circuit responsive to the energization of any of said conductors, said electroresponsive means operating to permit the closure of only those trip circuits upon which abnormal conditions exist.

22. The combination with a time controlling device comprising a rotatable switch member, contacts adapted to be engaged by the rotation of said switch member in successive time intervals, motive means for automatically rotating said switch member, circuits operatively related to said contacts, and means controlling each circuit selectively ac tuatable to set said motive means into operation and to render their respective oil'- 5 cuits closable by the engagement of said switch member and their respective contacts. In Witness whereof, the said HEWLETT has hereunto set his hand this 3rd day of March, 1917; and the said BURKHOLDER has here untf?) set his hand this 5th day of March 1 191 EDWARD M. HEWLETT. CHARLES I. BURKHOLDER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of latents, Washington, D. 0.

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