US2258154A - Automatic reclosing breaker system - Google Patents

Description

Oct. 7, 1941. c. w.` WATSON 2,258,154 AUTOMATIC REcLosING BREAKER'SYSTEM Filed Feb. 5, 1938 2 Sheets-Sheet l M, G .G

VWQSS fifwlL Q lllllll I YIFL Q Oct. 7, Y1941. c.vw. wATsoN 2,258,154

AUTOMATICl RECLOSING BREAKER SYSTEM Filed Feb. 5, 1958 2 Sheets-Sheet 2 INVENTOR CHARLES W- WATSON ATTORNEY Patented Oct. 7, 1941 AUTOMATIC RECLOSING BREAKER SYSTEM Charles Wilbur Watson, Rocky Point, N. Y., assignor to Radio Corporation of America, a corporation of Delaware Application February 5, 1938, Serial No. 188,838

11 Claims.

My present invention relates to a means for automatically restarting electrical devices or for automatically reclosing an electrical circuit.

On electrical devices provided with overload or undervoltage protective devices, it is very desirable to automatically reclose the circuit as soon as the undesirable condition which causedY the operation of the protective devices has been cleared. This permits service to be restored with a minimum time lapse. However, within my knowledge, previous devices for automatic` circuit reclosure have been so complicatedand expensive that manual operation has been mainly relied on in the industry. Therefore, an object of my invention is to provide simple, inexpensive means for automatically reclosing an electrical circuit.

Another object of my invention is to provide an automatic circuit recloser device which will restore service as soon as the undesirable condition which interrupted service has been reimoved.

Still another object is to provide an automatic circuit recloser device which will, in case the firstr attempt to restart is unsuccessful, repeat the cycle a predetermined number of times and, thereafter, lock-out automatically.

Briefly, my invention comprises an electromagnetic relay with a plurality of contacts, the rst of which closes immediately upon an energization of the relay winding and locks in its energization. This operation is automatically controlled by the removal of the undesirable conditions which caused the circuit breaker to be tripped. A second set of contacts on my device are under control of a time delay device and after a predetermined time close and then reopen the control for the circuit breaker. If this operation of the control circuit is unsuccessful in reclosing thecircuit due to the undesirable condition continuing, or otherwise, my device may be adjusted to repeat the cycle either continuously or, after a predetermined number of reclosures, to lock-out automatically, or it may be arranged to lock-out after the iirst operation.

Referring, now, to the drawings for amore complete disclosure of my invention, Fig. 1 shows diagrammatically one form of my invention; Fig.y 2 shows a modiiication thereof; Fig. 3 shows a further modification of the form of my invention shown by Fig. 2.

Referring, now, to Fig. l, the device consists of an electromagnetic relay having winding I and armature 2. The armature is directly connected to contacts 3 which are closed immediately after the relay coil I is energized. Also connected to the armature 2 through time delay mechanism 4 is a control contact 5. In cooperating relationshipwith contact 5 is a contact 5' which is supported on an arm 6 which is pivoted at the center. The other end of arm 6 carries contact I which cooperates with xed Contact 1. Contacts 5 and 5 close under control of the time delay mechanism and shortly after these contacts are closed, due to the continued movement of the contact train, arm 6 is moved which causes contact 'I and 1 to break. However, the mechanism is adjusted so that 'both contacts remain closed for a short interval. This is accomplished by means of a small spring 5I supporting contact 5 and by so adjusting the mechanism that a portion of the operation of the time delay escapement mechanism takes place after contacts 5 and 5 close, but before contact 1 and 'I' open.

The typical time delay mechanism for use in my invention includes a spring 4I which is stressed under the influence of the armature 2 of the control relay. This spring causes arm 42 ,Y to be moved at a rate determined by clock-escapement 43 connected thereto through a rack and pinion mechanism. The operation of contacts 5 and 5 closes the control circuit connected to terminals I4, I5 for the electrical device which is to be restarted and after the desired time delay, which is determined by the spring 5I, contacts 1, 1 open the same control circuit.

A remote control relay B is provided having contacts 8 connected in series withA a source of energy and winding I of the relay. The winding of relay B is energized through terminals 9, 9 from a circuit in the main device or load which becomes energized when the device is ready to be started. This circuit and details of the main switch are shown in the lowerv part of the figure and will be explained more fully hereafter. A suitable indicator, alarm or counting device 20 is connected in parallel with relay winding I to give an indication of the operation of my device.

The operation of my device is, briey, as follows:

The overload, undervoltage or other protective devices are arranged to operate interlock switches I0 whenever the correct conditions exist for operation of the mainy device or load, and when it is desired to energize the load. These switches may be operated by safety doors around the load, temperature responsive devices on bearings, etc. The interlock circuit also contains a switch 'II operated by magnet 'l2 Whenever the load draws more than a predetermined current. This circuit supervises the operation of the load and causes disconnection to take place under abnormal conditions. The recloser control switch I6 is left open and the main device or load energized in a normal manner by means of the on push-button I8. Closure of normally open switch I8 closes a circuit from I3 through normally closed switch I9, switch I8, arm 6, contacts 1', 1, terminal I5, recloser coil 13, switch 1I, interlock switches 10 and back to I3, the other side of the supply line, thus actuating recloser 13. This actuation closes contacts 14 and 15. Closure of contacts 15 energizes the lactuating coil 68 of main switch 69, thus energizing the load 6I from the alternating current supply. Main switch 60 is of a conventional type having moving contacts 62, 53 engaging stationary contacts 62' and 63 and carried by an actuating arm 64. Arm 84 also causes back contact 65 to engage contacts 65 when the main contacts are opened.

Closure of contacts 14 closes a locking circuit for coil 13 through a circuit which may be traced from I3 through switch I9, terminal I4, contacts 14, coil 13, switches 1I, 1I) and back to I3. As soon as main switch 60 closes terminals 9, 9 are automatically de-energized by the opening of back contacts 65, 65 on the main switch 60. The recloser control switch I6 is then closed and the device is ready for operation. In case switch 1I is opened due to load 6I drawing excessive current through coil 1I, or any of the interlock switches are opened, the locking circuit for coil 'I3 is opened and main switch 6D opens closing contacts 65, 65. As soo-n as switches 10 and/or 1I return to normal, a circuit is closed from line 83 through contacts 65 and E5, terminal 9, Winding of relay B and lamp I9, terminal 9', switches 1I, 1i) and thence to line 83. Energization of this circuit and lighting of lamp IIJ constitutes a signal that the load circuit is in proper condition to be energized from the supply line. Contacts 8 of this relay B close and supply power to the coil I of the reclosing relay. This causes contacts 3 to close and also causes an energization of the indicating device 20. The time delay mechanism 4 will be started in operation at the same time. Contacts 3 hold the reclosing relay coil I energized as long as the lock-out I1 and recloser control switches I6 remain closed. This circuit may be traced from terminal I3 through coil I, switch I1, contacts 3, switch I6, switch I9 to terminal I3.

When the desired amount of time has elapsed, as determined by the escapement 43, contacts 5, 5 close while contacts 1, 1 remain closed for a short interval. This closes the circuit around the on push-button I8 completing the circuit between the terminals I4, I5, which recloses the main switch 6G as heretofore described for manual operation of switch I8. Contacts 1, 1' then open but coil 13 is by that time locked in by closure of contacts 14 provided the lock-out switch I1 and recloser control switch I6 remain closed. If the lock-out switch I1 is closed it will thus be seen that the device will make a single attempt at reclosure and then remain locked out until the control switch IE is opened by manual or automatic means, thus breaking the locking circuit for winding I of the recloser except in the case of a complete power failure, in which case it will repeat its cycle, A failure of the power supply will cause the main switch to `open due to de-energization of coils 68 and 13.

When the recloser has locked out it is put in readiness for another operation by simply opening and then closing the control switch I6, either by manual or automatic means. This breaks the locking circuit established through contacts 3 allowing armature 2 to drop back. If the lock-out switch I1 is left open the reclosing device will re-cycle itself each time terminals 9, 9 are energized. This will give a series of single timed reclosures without lock-out each time the main switch 60 connected to the load is opened.

Referring, now, to Fig. 2, which is similar to that shown in Fig. 1, except that a contact 3 cooperating with contact 3 is arranged on a movable arm similar to that employed with respect to contacts 5 and 1. The end of the arm opposite Contact 3 carries a contact I I cooperating with a fixed contact II. This construction replaces the lock-out control switch I1, shown in Fig. 1. In this modification control button I 8 is arranged to maintain the circuit closed as long as operation is desired. In case the main load is de-energized due to the operation of protective devices associated therewith, or due to a power failure, the terminals 9, 9 will, as before, be re-energized at the proper time, control relay will close its contacts 8 energizing the recloser relay coil I through a circuit from terminal I3 and including control switch I6, relay coil I, contacts 8, the control buttons I8, I9 and thus back to the power supply terminal I3. Contacts 3, 3 immediately close, short eircuiting the control relay contacts 8 and locking in the recloser relay coil I. Recloser coil 13 is also energized through a circuit extending from I3' through manually closed switch I 9, switch I8, contacts II, II, arm 6, contacts 1, terminal I5, coil 13, switches 1I and 10 and back to terminal I3, thus immediately reclosing switch 60. The contacts II, II open a short interval after contacts 3, 3 have closed which prevents any further energization of coil 13 until contacts 5, 5 are closed` This completes the first immediate reclosure.

When the desired amount of time has elapsed for the second attempt at restarting as regulated by the time delay mechanism 43, contacts 5, 5 close while contacts 1, 1 remain closed for a short interval, as before. This again energizes the circuit for coil 13 effecting a second reclosure in case the first one has been unsuccessful. Contacts 1, 1 then open after a short interval preventing any further attempts at reclosure as long as the control switch I6 remains closed, except in the case of a complete power failure. The recloser has now reached the end of its time cycle and is locked out.

To return the recloser to its normal ready position it is necessary to open and then close the control switch I6 if the main switch 60 is closed. If the main switch 60 is olf, the control switch is opened, the main switch 60 closed with push-button I8, as described before, and the recloser control switch thereafter closed to place the recloser in operation.

The modification shown in Fig. 3 is a further modification of that shown in Fig. 2 in that there has been added time delay relay 2I with its coil in parallel with the recloser coil I and its contacts 52 arranged in series with the recloser control switch I6. The time delay may be provided by a clockwork escapement similar to escapement 4 if desired. With this arrangement the circuit is immediately interrupted after any desired time following its first operation, thus recycling the recloser through the previously described operations automatically. The form of sim- While I have described my invention in some'k detail I do not Wish tobe limitedto the particular'embodiments shown but intend to include all modiiications wit-hin the scope of my invention.

I claim:

1. An automatic circuit recloser comprising an electromagnet, means under control of protective devices associated with aload for energizing said electromagnet, a locking circuit for said electromagnet, meansy responsive to the operation ci said electromagnet for energizing said looking circuit, a time delay mechanism actuated by said electromagnet and means responsive to the operation of said time delay mechanism for closing a control circuit for energizing said load, a relay connected inV parallel with said electromagnet and having its. contacts arranged to momentarily de-energize said electromagnet a predetermined time after the operation of said last mentioned means whereby the recloser will repeat its cycle of operation.

2. An automatic circuit recloser comprising an electromagnet, means under control of protective devices associated With a load for energizing said electromagnet, a locking circuit for said electromagnet, a first pair of contacts in said locking circuit actuated by said electromagnet, a time delay mechanism actuated by said electromagnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing a control circuit for energizing said load, a third normally closed pair of contacts in series with said second pair and responsive to the operation of said time delay mechanism for opening said control circuit after a predetermined time.

3. An automatic circuit recloser comprising an electromagnet, means under control of protective devices associated with a load for energizing said electromagnet, a locking circuit for said electromagnet, a first pair of contacts in said locking circuit actuated by said electromagnet, a time delay mechanism actuated by said electromagnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing a control circuit for energizing said load, a third normally closed pair of contacts in series With said second pair and responsive to the operation of said time delay mechanism for opening said control circuit after a predetermined time and a relay connected in parallel with said electromagnet and having its contacts arranged to momentarily de-energize said electromagnet a predetermined time after the operation of said last mentioned means whereby the recloser Will repeat its cycle of operation.

4. An automatic circuit recloser comprising an electromagnet, means under control of protective devices associated with a load for energizing said electromagnet, a locking circuit for said electromagnet, a first pair of contacts in said locking circuit actuated by said electromagnet, said first pair oi contacts being also arranged to close a control circuit for energizing said load, an auX- iliary normally closed pair of contacts in series with said first pair and actuated thereby for opening said control circuit, a time delay mechanisrn actuated by said electromagnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing said controll circuit,l a third normally closedpair of contacts in series Withsaid second pair and responsive-'to the., operation of` said'timefdelay mechal, nism'for opening said control circuit after a predetermined time.

Y 5. Any automatic circuit recloser comprising an electromagnet, means under control of protective devices associated with a load for energizing said electromagnet, a locking circuit for said electro- "magnetg a iirst pair of contacts in said locking circuit' actuated byV saidl electromagnet, said first pair of contacts being also arranged to close a controly circuitfor energizing said load, an auX- E,iliary normally closed pair of contacts in series With said first pair and actuatedV thereby for f trolv circuit, a third normally closed pair of contacts in series with said second pair and responsive to the operation of said time delay mechanism for opening said control circuit aftera predetermined tirne, and a relay connected in parallelwth said electromagnet and having its contacts arranged to momentarily de-energize said electromagnet a predetermined time after the operation of said last mentioned means whereby the recloser Will repeat its cycle of operation.

6, A control mechanism for association With circuit breakers, said mechanism including a circuit Which when closed causes a closing of the circuit breaker, a second circuit which When closed indicates an operative condition of the load connected to said breaker and relay means responsive to a closed condition of said second circuit for energizing an electromagnet and locking an energizing circuit for said electromagnet, a time delay mechanism actuated by said relay and means responsive to the operation of said time delay mechanism for closing for a predetermined time said first mentioned circuit.

'7. A control mechanism for association With circuit breakers, said mechanism including a circuit Which when closed causes a closing of the circuit breaker, a second circuit which When closed indicates an operative condition of the load connected to said breaker and relay means responsive to a closed condition of said second circuit for energizing an electromagnet, a first pair of contacts for said electromagnet, a time delay mechanism actuated by said electromagnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing said first circuit and a third pair of contacts actuated by said second pair of contacts for opening said first circuit.

8. A control mechanism for association with circuit breakers, said mechanism including a circuit which when closed causes a closing of the circuit breaker, a second circuit which When closed indicates an operative condition of the load connected to said breaker and relay means responsive to a closed condition of said second circuit for energizing an electromagnet, a first pair of contacts actuated by said electromagnet, a time delay mechanism actuated by said electromagnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing said iirst circuit and a third pair of contacts actuated by said second pair of contacts for opening said nrst circuit, said first pair of contacts being arranged to energize a locking circuit for said electromagnet.

9. A control mechanism for association with circuit breakers, said mechanism including a circuit which when closed causes a closing of the circuit breaker, a second circuit whch when closed indicates an operative condition of the load connected to said circuit breaker, an electromagnet, means responsive to a closed condition of said second circuit for energizing said electromagnet, a first pair of contacts arranged to be closed by said electro-magnet and to energize a locking circuit therefor, a time delay mechanism actuated by said electro-magnet, a second pair of contacts responsive to the operation of said time delay mechanism for closing said first named circuit, a third pair of contacts in series with said second pair of contacts and actuated thereby for opening said iirst named circuit whereby an impulse of predetermined length is impressed on said circuit. y

10. A control mechanism for association with circuit breakers, said mechanism including a circuit which when closed causes a closing of the circuit breaker, a second circuit which when closed indicates an operative condition of the load connected to said circuit breaker, an electromagnet, means responsive to a closed condition of said second circuit for energizing said electromagnet, a locking circuit for said electro-magnet, means responsive to the operation of said electromagnet for energizing said locking circuit, a time delay mechanism actuated by said electro-magnet and contact means connected to and responsive to the operation of said time delay mechanism for closing said rst named circuit for a. predetermined time.

11. A control mechanism for association with circuit breakers, said mechanism including a circuit which when closed causes a closing of the circuit breaker, a second circuit which when closed indicates an operative condition of the load connected to said circuit breaker, an electromagnet, means responsive to a. closed condition of said second circuit for energizing said electromagnet, a locking circuit for said electro-magnet, means responsive to the operation of said electromagnet for energizing said locking circuit, a time delay mechanism actuated by said electro-magnet and contact means connected to and responsive to the operation of said time delay mechanism for closing said iirst named circuit for a. predetermined time, and a switch in said locking circuit for disabling said locking circuit.

CHARLES WILBUR WATSON.

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