US 3100854 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Filed sept@ e, 1961 A118- 13 1963 R. E.l RIEBs 3,100,854
REPEATING CIRCUIT INTERRUPTER 3 Sheets-Sheet 1 Aug. 13, 1963 Filed Sept. 6, 1961 REPEATNG CIRCUIT INTERRUPTER R. E. RIEBs 3,100,854-
3 Sheets-Sheet 2 Jaw H R. E. RIEBS REPEATING CIARCUIT INTERRUPTER Filed Sept. 6, 1961 *.3 Sheets-#Sheet 5 i IN VEN TOR, HL2/wat'. fP/s @Trai/vir 3,160,854 REPEATING CmCUiT INTERRUPTER Richard E. Riebs, Hales Corners, Wis., assign'or to McGraw-Edison Company, Milwaukee, Wis., a corporationy of Delaware f Filed Sept. 6, 1961, Ser. No. 136,352
12 Claims. (Cl. 317-22) This invention relates to repeating circuit interrupters and, more particularly, to the class circuit interrupters commonly known as Reclosers A Recloser may be characterized as a circuit protective ydevice having Ifault-sensing means connected to the system being protected and which is 'responsive to overload currents to initiate a switch-opening openation, switch reclosing means operable lafter each opening operation, normally inactive time delay means, and opera-tion counting and lock-out means which is operable to initiate time `delayed switch opening after a predetermined number of opening operations.
`It is common practice to utilize repeating circuit inte-rrupters of this type in conjunction with other protective devices such as fuses. For example, a distribution system may be provided with a repeating circuit interruptor or recloser connected in series with themain line and located adjacent to the source power and fuses disposed in feeder lines radiating from the main line. Because the majority lof aults in such systems are temporary in nature and will clear in a relatively short time, it is common to arrange the switch opening means to execute a series of rapid opening opera-tions so that the period in which the system remains energized is shoi'ter than the time necessary `for the fuse element :to melt. In addition, the circuit breaker contacts must remain open for a suiiicient period of time to fallow. the fuses to cool. If the fault does not clear during this initial series of rapid operations, the time-delay means is actuated by the operation counting means so that there'follows la second series of operations in which the reclosers contacts remain cl-osed for a period of suiiicient length to allow the fuse elements to melt. If Ithe faul-t stil-l has not cleared [after a number of such time `delayed operations, it is considered permanent and the operation counting means prevents the actuation of the reolosing means so that the device is locked open. In |addition, it is Idesirable for the opening and reclosing times of such reclosers to be suiiiciently flexible so that they may be readily coordinated with ta plurality of relatively slowly operable circuit breakers.
it is an object of the invention to provide a repeating circuit interruptor having electroresponsive switch-opening means with selectively interchangeable time-'delay means and means tor successively actuating said selectively interchangeable time-delay means during successive switch-opening operations.
A further `object of the invention is to provide a 4repeating circuit interrupter having reclosing means and a selectively interchangeable time delay means operable to initiate reclosing after each opening operation.
These and other yobjects and advantages of the instant invention will become more apparent Ifrom the detailed description thereof taken with the accompanying drawing in which:
FIG. l is a perspective view of a repeating circuit interrupter incorporating t-he instant invention;
FIG. 2 is a schematic illustration of the electrical control for the recloser shown in FIG. l;
FIG. 3 shows the overcurrent responsive por-tion of the control illustrated in FIG. 2; 'and FIG. `4 shows the control cabinet of the recloser illustrated in FIG. `l. t
VIn general terms the invention comprises a repeating circuit interruptor having operating means for selectively performing switch opening and reclosing oper-ations. Control means are also provided andl include-sensing means operable upon the occurrence of an Aabnormal circuit condition to initiate the operating means in the execution of a switch opening anda switch reclosing operation. The control means also includes time delay circuit means -for delaying at least one of said operations and having disconnect plu-g means for electrically and mechanically coupling it to the control means. In this manner the time ldelay means may be selectively removed from circuitry with the operating means and replaced by time delay means having diiierent time delay characteristics.
Referring now to the ldnawings in greater detail, FIG. 1 shows la repeating circuit interrupter or reclose-r 6 housed in la metallic container and mounted on a metal tramework 7. A separate control housing -8 is mounted on the frame 7 Iand is electrically connected to the recloser by a cable 9; Terminals 2li and 21 connect the recloser 6 to the polyphase system being protected.
The repeating circuit interruptor 6 is shown in FIG. 2
to genenally include main interrupting switches 10, overloady responsive means 12, switch-opening means 14, switch-closing means 16, and operation counting and lockout means 17. The overcurrent responsive means 12 is operable to actuate the switch-opening means 14 upon the occurrence of an overload in the system being protected so that the interrupting :switches 10 will each be moved to their open positions. Upon this event, reclosing means 16 ismacle operable to return the interrupting switches 10 to their closed position. The operation-counting and lock-out means 17 which includes steppingrelay 18 and step switch 134, is operable to initiate time-delayed open and/ or reclosing operations if the fault has not cleared after an initial series of rapid operations and to prevent reclosure of the main switches 16` if the fault does not clear after a second series of Isuch delayed operations. For a more complete description of a circuit breaker operating mechanism usable with the illustrated control mechanism, reference is made to `co-pending application Serial No. 5 6,259 led September 15, 1960.
The overcurrent responsive means 12 is shown coupled to phase A of a polyphase system by means of a current trans-former 22 and a tull wave rectifier 24. As will be seen hereinafter, the overcurrent responsive means 12 is similarly connected by means of current transformers and .full wave rectiiiers each of the other phases B and C. The overcurrent responsive means 12 includes an overcur-rent sensing pontion 26, a timing portion 27 and an output portion 28. The overourrent responsive means 12 will be discussed in lgreater idetail below, it being su-fcient at this point to state that the overcurrent sensing portion 25 is operable when the rectified current at the output of rectifier 24 exceeds a minimum value to pnovide a signal to the timing portion 27. Upon the receipt of this signal, the timing portion 27 initiates a timing operation, and after a predetermined interval provides a signal to the outputl portion 28 which initiates a switch opening operation by closing contacts 43.
The switch opening means 14 is Ishown in FIG. 2 to include an electromagnetic ltripper 30 having a plunger 32 and a coil 35. The plunger 32 is mechanically coupled to a latch crank 33 which is normally urged in a clockwise direction about pivot point 34 by a reset spring 35 to hold the main switches 10 in closed position against the influence of opening spring `69. 'Ilhe trip coil' 36 is connected by conductor 37 to the negative power supply terminal ttll and by a conductor 42 to contacts 43. Conductor 44 connects the other side ocE contacts 43 through a step switch ,134 to the positive power supply terminal 46. The purpose of the step switch 134 will be discussed more fully below, it being suicient at this point to state that under normal conditions of operation, it is initially on contact a. Contacts 43, which are mechanically connected to the output portion 28 of the "overourrent responsive means `12, are normally openV so-that coil 36 remains de-eneugized under normal conditions. l
Upon the occurrence lof a fault in `one of the phases, A, B or C, output portion 28 will be made operative to closed contactsj43, thereby energizing coil 36. Upon this event, the latch crank 33 will be rotated a counterclockwise direction to release the main switches for movement toward their -open position under the influence of opening spring 69. When the main switches 10 open, contacts 43 are returned to their lopen position to 1deenergize trip coil 36 so that latch crank 33 may be returned to its initial position by reset spring 3S. The trip portion 14 is thereby reset in a position to relatch the main switches 10 when they are returned to their closed positions.
Before continuing the discussion of the mechanical por- 'tion of the reclosers control, the operation of the stepping -relay 18 will be mentioned brieily. rIlhis device accomplishes operation counting and lock-out of the recloser in conjunction with step switch 134. IIn addition, the stepping relay 18 is also operable to chan-ge the time -delay tfor the opening and `reclosing operations by operating the tap switches 146 and 147 in the timing portion 27 of rovercurrent responsive means 12 and the time delay relay bank 121, respectively. Prior to the first opening operation, the step switch 134 and tap switches 146 and 147 are each disposed ion position a. The stepping relay .'18 is connected by conductors 38 and 45 in parallel with the opening coil 36. When contacts 43 are closed by Ioutput portion 28 upon the occurrence of a ffault, therefone, the circuit between the negative and positive terminals 40 and 46 will be completed through stepping relay 18 which then operates stepping switch 134 and tap switches `146 and 147 to their positions b. 'Ih-us, it can be seen that each time the device executes an opening operation, the relay 10 will adr/ance each of the switches 134, 146-and=147 one position.
The reciosing assembly 16 includes a closing coil 120, a time ldelay relay bank 121 and normally open contacts 122 which are mechanically connected to the main switches 10. Conductors 124 and 125 connect the closing coil 120 to the negative supply terminal 40 through the contacts .122. Conductor 130 connects the other side of closing coil 120 to the time delay relay bank 121 which in turn is connected to the positive power supply 46 through step switch 134.
WhenY the main switches 10' are in their closed position, contacts 122 are 'lopen so that the closing coil 120 and the time delay relay bank 121 will be de-enengized. When the main switches 10 reach their tully opened positions, the contacts 122 will be closed Ito complete the circuit through the time Idelay relay bank 121. As will be discussed more tully bel-ow, the time delay relay in bank 121 that is connected to tap b will close after a time delay to complete the circuit through closing coil 120. 'Ilhis attracts the magnetic plunger 93 upwardly toreclose the main switches 10 and extending the opening spring 69 to store energy for the succeeding opening operation, and opening contacts 122 to `de-energize the closing coil 120` and the time delay relay bank 121.
FIG. 3 shows the idetails of` the overcurrent sensing portion 26, the timing portion 27 and the output portion 28 lof the overload responsive means 12. Circuit 12 is coupled with the phases A, B and C rby current transfformers 22, 22 and 22 respectively and corresponding ttull wave rectiiiers 24, 24 and 24" whose secondaries are connected in parallel so that the current flowing to circuit v12 is proportional to the highest peak current flowing to any said reotiiers. In order to limit the current owing to the circuit 12 resistors 200, 200 and 200 are connected across each of the secondaries of current transformers 22, 22 and 22'! respectively.
The timing portion 27 of circuit 12 includes four iden- Y tical timing circuits which are each connected to one of the taps a, b, c and d of tap switch 147 `and correspondingly labeled 201a, 20112, 201e and 201d. Because eachy of the timing circuits is identical, except-oi course for the size of its components which determine its time .delay/,g only timing circuit 201e will be discussed in detail, for
the sake of brevity. This circuit is shown to'include a timing capacitor 202 connected in series with a timing resistor 204 and a diode 206. A second timing resistor 207 is connected in parallel with this series combination. As more fully discussed in co-pending application Serial No. 800,567, iiled March 19, 1859, and assigned to the In operation, the current tlowing in the collector of the charging transistor 208 which is a function of the voltage across capacitor 205 will split between the parallelpathsdelined by the timing resistor 20-7 and the series combination of timing resistor 204 and timing capacitor 202.Y When there is no fault in any of the phases, capacitor 202 is prevented from charging because it is shunted by leakage resistor 209 through diode 210 and conductor 211. The current iiowin-g to the overcurrent sensing portion 26 through conductor 212'is also proportional to the highest peak current in any of the phases A, B or C and causes la transistor 213 collector current to ow through resistors 214 and 216 thereby raising the potential of the junction point 21,7 between them to a value which is also proportional to said peak current. A transistor 218 emitter current, which is controlled by the potential of ju-nction point 217, iiows throughV a resistor 220 and thereby also raises the potential of junction point 221 to a value proportional to said highest peak current. The base of a signal comparing transistor 222 is connected to junction point 221 while its emitter is connected to junction point 223 which is held at a iiXe-d potential by a Zener diode 224 and a resistor 226. Thus, by a proper selection of components, when the highest peak current of any of the phases A, B or C equals or exceeds the desired minimum actuating current of the device, the base voltage of transistor 222 can be made to exceed its emitter voltage so that collector current will begin flowing therefrom to the base of a-n output transistor 227. Upon the latter event, the base potential of transistor 227 will fall below its emitter potential whereupon current will begin flowing to the leakage resistor 209. This, in turn, raises the potential at junction point 228, between the collector of transistor 227 and conductor 211, above that across timing capacitor 202. As a result, timing capacitor 202 -is prevented from discharging through leakage resistor 209 and therefore, begins charging. In this manner, the timing operation is initiated. Diode 210 performs the function of preventing reverse current ow from junction point 228` to the charging capacitor 202.
As timing capacitor 202 charges up, the voltage .at junction point 230, Ibetween diode 206 and the base of a coupling transistor 231 in the output portion 20, will begin raising so that the emitter current flowing in transistor 231 `and transistor 232, which are proportional to Y the voltage at junction point 230 will similarly rise. The
potential of junction point 233, resulting from the transistor 232 emitter current will, therefore, also follow the potential of junction point 230'. The base of a transistor 234, which is connected to junction point 233, will, thereconnected across the power supply terminals 4tilan'd 46.` After timing capacitor 202 has chargedfor a predetermined time, which is ythe time delay for the vfirst operato again open the main switches 10;
tion of the device, the potential of junction point 233 will exceed the potential on the emitter of transistor 234 and said transistor will conduct, pass-ing emitter current to the relay 237 which, in turn," closes lcontacts 43 to open the main switches 1d in the manner described' hereinabove. In addition, stepping relay 18`will also be energized so that tap switch 147 will be moved to contact b thereby connecting time delay `circuit 20112 and disconnecting time `delay circuit 20M. Should the fault reappear the time delay of the second opening `operation will be dictated bythe components of time delay circuit 2111i).
The time delay relay bank 121 is'shown in FIG. 2.t o
include three distinct time delay relays symbolized by coils 121b, 121C and 121d, although it will be 'appreciated by 4those skilled in the art that any type of time delay relay, such as the thermal type, may be employed. Each coil 1211), 121C and 121d is connected between the corresponding taps b, c and d ori switch 147 and the negative supply terminal 40' and each coil is operative upon being enengized `and after a time delay, to c lose the appropriate contacts 121b, 121C or 121d', to complete the circuit between the rclosing coil-121i` and taps b, c and d of switch 147. y
Assume, for Vthe sake of illustration, that it is desired to have the recloser execute two rapid and two time delayed opening. operations, a single rapid and two time delayed reclosin'g operations followed by lock-out. As `a result, relatively short time delay circuits will be connected by disconnect plugsZia and 240b to contacts a and b of the timing portion 27 while long time delay circuits will be connected by disconnect plugs 24de and 240d.
to tap c and d respectively.'y In addition, disconnect plugs 242e, 242b, 242c'and 242d connect each of the time delay circuits to the input transistor 208 while disconnect plugs 244:1, 24412, 244e Iand 244d connect each of j the time ldelay circuitsV to' the overcurrent sensingportion In alike manner, after the third opening operation, stepping relay 18 will move with each of the switches `134, 146 and 147 to their positions d, lwhereupon closing coil 120 willbe energized through contacts 121d after a time delay. If the fault continues after therthird reclosing operation, switch 43 'will bereclosed after a time delay dictated by the time delay circuitZtlild.` This will again energize the trip coil 36 and stepping relay I1S which will thenr move each of the tapv and stepping switches to the dummy contacts e. j
It can be seen that because contacts e of switches 134 and 147 are dummies, closing coil 120` is now open circuited even though contacts 122 are closed when the main switches 10 are open. VIn this manner, the recloser is locked in open position after `a predetermined number of opening and closing operations.
it can be seen in FIG. 2 that diodes 148C and 14891 willisolate each ofthe taps `C and D respectively' of switch V134 from the one immediately preceding it, e.g., diode 148e isolates tap c from tap b, etc.y This allows the number of operations before lock-out to be adjusted.
' Vin the preceding discussion, when lead 149V was connected tol tap d, there were four opening operations prior to lock-out. Assume, however, that only two opening operationsvbefore lock-out are desired. Here lead 14,9 will be connect-ed to tap b. After the iirst opening operation switch 134 will be on tap b and reclosure will occur in the above described manner. After the second opening operation, however, switch 134 will hev on tap c and hence isolated by diode 148C lfrom lead 149 and, as a result, from the closing coil 120.' Thus, the reclosure is locked out after two operations. Similarly, by connecting lead `149 to tap c there =will be three operations to lock-out and by opening switch 149 there will be one operation to lock-out.
Resetting of the recloser after it has locked out elec-V tricaliy is accomplished by means of a` manual reset cally coupled'to stepping relay 18. It will be remem- A bered that after lockout each of the step and tap switches taps c and d. Taps e and fof switches 134, 146 and 147 are dummy `contacts for the purpose of lock-out as will be explained in greater detail below.
The first opening operation will he rapid because contact a of switch `147 is connected to a short time delay circuit and because stepping relay 18 has not 'as yet operated. As a result, the output portion 2S will close contact y43 a relatively short time after the fault is sensed byovercurrent sensing portion 26. This energizes trip coil 36 which opens the main'switches 1d and also the stepping-relay 18 which movesrthe stepping switch 134 andjtap switches 146 and 147 to their b positions. Movement of tap switch 147 Vto contact b completes'the energizing circuit through short time delay relay 12llb,l which, after a short time delay, closes contacts 1Z1b' to 134, 1146 and 147 as well as 167 will each be connected to taps e. When reset button 165 is depressed stepping relay coil 18 will be energized from the lpositive terminal 416 to the negativel terminal 40 through a path dened by tap e of step switch 167, conductor l175, switch 171, and conductors 172, 38, `45 and37. Upon being energized stepping relay 18will move each of the tap and step switches l,to their positions f. An energizing circuit to stepping relay 18 is then completed through the tap j"Y on step switch 134, conductors 174, 175, switch 171, and conductors 172, 38, v45 and 37. The stepping relay 13 then moves each of the switches to their taps a whereupon they are in position for a switch closing op- 18 and trip coilV 36 prevents energization of the latter during the resetting operation just'described.
energize the closing coil through switches 134 and v 147, conductors 44, 130, `124, and 'contacts 122 which are closed when the main switches 10 are open.
Should the fault persist, the output portion 281 will again be energized after a short time delay to close contact l43. This will again energize trip coil 46 and stepping relay 18` so that switches134, 146 and 147 will each be moved to their taps c whereupon time delay coil 121C will be energized to' close contacts 121C' after a time delay and thereby energize closing coil 12()l and initiate a second reclosingoperation. Similarly, should the fault persist after the second reclosing operation, trip coil 36 will be energized after a relatively long time delay After the step and tap switches have been cycled to their positions a1 byres'et button `165 the main switches 1d are reclosed by closing switch 169 which completes an energizing circuit to closing coil 120 around the time delay Vrelay bank y121.
It will be recalled that the recloser will cycle itself to i lockoutonly if the fault current persists after a predetermined nurnberof opening and closing operations. In order to reset thejdevice shouldthe fault clear after a lesser number of opening and reclosing operations, the time delay reset assembly is provided. This includes Ia time ldelay'relay coil 186 connected through diodes 186B, 186e and 186D to taps b, c and d of step switch 147 and in parallel with the corresponding time delay relay windings 12119, 12.10 and 121d. Time delay relay winding 186'is operable when energized to close normally open contacts 187 Iwhich shunts reset button 165. Assume, for example, that after a single opening andreclosing operation the fault clears so that switch 43 remains open and step switch 18, trip coil 36- and reclosing coil 120` remain de-energized. As a result, each lof the step and tap switches will be in theirY positions b.
Thiswill energize time delay coil 185 through diode 186. Y After a time-delay, which is longer than the combined time delays of relays 7121,17, 121e and 121d and eachofv gardless ofthe position of the control circuit of FIG. 2,
contacts 190 are shown coupled to the main switches 1t]` land closed when said main switches Iare closed. Should a fault occur in one of the phases when Ithe control circuit is in lock-,out condition, switch 43 will be closed to open the main switches .thereby providing protection tothe system A, B and C.
Referring now to FIG. 4, the metallic control housing y8 is shown with its front access door 252 pivoted to its 'open position. Certain `of vthe components of the control circuit `are shown to be mounted on a panel 254 which is mounted by hinge-s 255 to one of the side walls of the housing 8 so that it may be swung outwardly relative to said housing to expose the remainder of the control system components.
Each :of the time delay circuits 201er, 2Mb, 201e `and g Mildare shown'to be disposed in `a metallic tube 256. `Eor purposes of illustration tube 256e, containing the time delay circuit 2010, is shown with parts brokenaway `and removed rto expose socket 257e yfor receiving the disconnect plugs 240m 242a and 244a which connect the time delay circuit 201101 to the overload responsive circuit 12. Tube 256a is shown to include an insulating' base 260l to which the disconnect plugs 2Min, 242a and v244er are Iatiixed. Also Medto the base 260 and extending normounted on a'nonconducting base 275i` such as glass. The lower endsof the elements 267 and 268 are further separated by porcelain blocks 272. A Bakelite cap 274 is ailixed to the base 27dA and supports the disconnect plugs 2li-6b, 243i) and 25% which are connected :to the coil 12115 and the contacts 1Mb' through the elements267 and 263 in the manner shown in FIG. 3.1 Element 268- is not materially affected by the heater coil l21b and pro-` vides ambient temperature compensation.
Thus, each of the time delay closing relays may also be rapidly removed from the circuit and a relay 'having' a different time `delay'value substituted therefor. Thus the time delay of each closing operation may also be rapidly modified while the recloser 6 remains in service. Y t While only a single embodiment of, the invention has been shown and described vand while the invention has been discussed with reference to one type of circuitrinterrupter,
, it is not intended that the invention be limited thereby mal-ly thereto isp-a nonoonducting circuit board 262 which i carries a row of terminals 263 along each of its sides.
Y The components of the circuit 20111, capacitor 202, resistors 204 Yand 207 and diode 206, are soldered at their opposite ends to pairs of terminals; 263. Cirouitry (not shown) at the rear of the circuit board 262 connects these elements in the manner shown in FIG. 3 and to the disconnect plugs 240W, 24261 and 244er. l
By mounting the time `delay circuits 20-1a, 2Mb, 201e and 20'1d in this manner each may be rapidly removed from the `overload responsive circuit 12 and a time delay cincuit having a different time delay rvalue substituted therefor. As a result, the-time delay of the recloser 6 may be rapid-ly Iand easily modified by changing one `or more of thel time ldelay tubes 256a, 25611, 256e or 256d. In addition, it will be lappreciated that this may be accomplished merely by lopening cover 252 of the housing `S and without Vremoving the reclo-ser 6 from service. This is contrasted with priorV devices wherein modiiication of the time delay couldfonly be accomplished by removal off -therecloser 6 from service and then removing its metallic housing.
yIn a similar manner each of the time delay closing relays in vbank 11.21 are disposed in corresponding tubes 265b, 265C and 4265d respectively. 'The tube 26511 is shown with partsfbroken away land removed to expose the socket264b for receiving its `disconnect plugs 246C, 248e and 250e 'which connect them to the time ldelay relay bank 121. The illustrated relay 221b is lof the thermal type although any 'well known type may be employed. In general, the device includes a heater coil 121b mounted on a mica plate 266 and a pair of oppositely oriented bimetallic elements 267 and 268 which carry the contacts 221b at their upper ends and 'whose lower ends are but only by the scope of the appended claims.
I claim: l.` A repeating circuit interrupter including main switch means in circuit with an electrical system, operatingmeans for selectively'performing switch opening and switch v rec-losing operations, control means for saidoperating means including sensing means operable upon the occurrence of an abnormal condition in said system to actuatesaid operating means in the execution of a switch opening operation and a re-closing operation, time delay circuit means for `delaying at least one of'said operations, disconnect plug means electrically and mechanically coupling said 'time delay means to said control means so that said time delay means may be selectively removed ifrom circuitry with said operating means andV replaced by time' delay circuit means having different time kdelay characteristics.
2. A repeating circuit interrupter including main switch Y means in circuit with an electrical system, operating means for selectively performing switch opening and switch reclosing operations, control means -for said operating means including mounting means, overload sensing means operable upon the occurrence of an overload in said system to Y actuate operating means in the execution of a series of switch opening and reclosing operations, a plurality of 1 rengageable with `one of said socket means for supporting each of said time delay means on said mounting means yand electrically connecting the same to said controlfrneans, means operable after each opening operation of said main- ,l
switch means to couple one cf said plurality of time delay means to said operating means so that the time delay of each succeeding delayed operation may be controlled, said disconnect plug means allowingsaid time `delay means'to be selectively removed -irom said circuit interrupter and replaced by time delay circuit means having `different time delay characteristics.
3. A repeating circuit inte pter tor protecting an electrical system and including. main switch means in oircuit 'with an electrical system, electroresponsive switch opening means and electroresponsive switch reclosing means; control means for said circuit interrupter, a mou-nting panel `for supporting said control means, said control means including a iirst and second time delay circuit means each of which is disposed in an individual envelope, a plurality of socket means in said mounting panel, disconnect plug meansV associated with each of said envelopes and enga-geable with said socket means for securing said time delay means to said panel and electinically coupling the same to said control means, and'overload sensing means coupled to said system and opera-ble upon the occurrence of an overload to actuate said switch opening means through said lirst time delay circuit means, said switch closing means being energized through said time-delay circuit means having dilferent 4characteristics.
4. A repeating circuit interrupter for protecting an electrical system and including mai-n switch means in circuit with anelectrical system, electroresponsive switch opening means and electroresponsive 'switfkshy reclosing means,
said circuit interruprter being disposed in a metallic housing; control means for said circuit interr-upter disposed exteriorly of said housing, `a mounting panel `for supporting said control means, cable means connecting said conl trol means to said switch opening and reclosing means,
'said second seriesfof time delay means to said switch closing. means, and overload sensing means coupled to said system and operable Yupon the-occurrence of an overload to actuate said switch opening means through a dilferent one' of said irst series of time `delay circuit means, said switch closing meansbeing energized through a different one of said second series of time delay means after each switch opening operation, said disconnect plug and socket means allowing the opening and reclosing time delays of said opening andrreclosing means to be selectively changed by substituting time delay circuit means having diiferent characteristics. i
5. A repeating circuit interrupter including main switch means in circuit with an electrical system, switch opening means, lcontrol means including overload ,sensing means operable upon the occurrence kofan overload in said system to actuate said switch opening means, a plurality of time delay Vcircuit means -for delaying the openings of said switch means, means operable ,after each opening operation of said main switch means to actuate a different one of said plurality of time delay means so that the` time delay` of each succeeding opening operation may be controlled, disconnect plug means electrically land mechanically coupling said `time delay means to said control means so that each of said time delay circuit means may be selectively removed from operative association withy said switch opening means and replaced by time delay circuit means having different time delay characteristics. i
-6. A repeatingcircuitinterrupter inclu-ding main switch means in circuit with anelectrical system, lswitch opening and reclosingV means; control means lfor said circuit interrupter including mounting means, overload sensing means operable upon theoccurrence of' an overload in said system 'to actuate said switch opening means, a plurality of time :delay circuit means for delaying the openings of said switch means andV each being secured to individual base means, a plurality of socket means in said mounting means, disconnect plug means secured to each of said base means and engageable with one of said socket means for supporting said time delay means on s aid mounting means and electrically connecting the same to said control means, means operable after each` opening operation of said main switch means to actuate a different one of said plurality of time delay means so said switch opening andreclosing means, said controll means including ia series of time delay circuit means, eajch 10 7. A repeating circuit interr-upter for protecting an elect'rical system and including main switch means in circuit with said system, electroresponsive switch opening means and switch reclosing means, said circuit interrupter being disposed in a metallic housing; control means for said circuit interrupter l isposed exteriorly of` said housing, a mounting panel =for supporting said control means, cable means connecting' saidcontrol' means to of said time delay circuit means being disposed an'individual envelope, a plurality of socket means in said mounting panel, disconnect plug means associated with each `of said envelopes and engageable with said socket means for securing said time delay means to said panel and electrically coupling the same to said control means, sequencing means actuable uponthe occurrence of each switch opening operation yfor sequentially coupling said time delay circuit means to said switch opening means and overload sensing means 'coupled to said system and operable upon the occurrence of 'an overload to actuate said switch opening means through a different one of said iirst series of time delay circuit means, said disconnect plug and socket means allowing the opening and reclosing time delays of said opening and reclosing means to be selectively changed by substituting time delay circuit means having diierent characteristics.
8. A repeating circuit interruptor including main switch means in circuit with an electrical system, switchropening means and electroresponsive switch reclosing means; control means for said circuit interrupter including overload sensing means operable upon .the coeur-rence of an over-v load in said system to actuate said switch opening means,
f means operable after each opening operation of said main switch means to complete an energizing circuit to said switch reclosing means, time delay circuit means for delaying the actuation of said reclosing means, disconnect w plug means electrically `and mechanically coupling said n by time delay circuit means having dieren-t time delay values. y
9. A repeating circuit interrupter including main switch means in circuit with .an electrical system, switch opening and reclosing means; control means for said circuit interrupter including mounting means, overload sensing means operable upon the occurrence of an overload in said system to actuate said switch opening means, means for actuating said reclosing means after each switch opening operation, time delay circuit means for delaying the closing said mounting means `and electrically connecting the v same to said control means, said disconnect plug means althat the time delay of each succeeding opening operation t may be controlled, said disconnect plug means allowing said time delay means to be selectively removed from .said circuit interrupter and replaced bytirne delay circuit means having different time delay characteristics.
lowing said time delay` means to be selectively removed circuit means having different time delayvalues.
10.'A repeating circuit interrupter for protecting an electrical system and including main switch means in circuit with said system, switch opening means and switch reclosing means, said circuit interrupter being disposed in ya metallic housing; control means for said circuit interrupter disposed exteriorly of said housing Iand including means responsive to an overload in said system to actuate said switch opening means, a mounting panel for supporting said control means, cable means connecting said control means to said switch opening and reclosing means, said control means including a series of time dei Y lay circuit means each of which Iare disposed in an individual envelope, a plurality of socket means in said mountsecuring said time delay means to `said panel and electrically couplingy the same tot said control means, sequencing means actuable upon the occurrence of each switch' opening foperationwfor sequentially coupling said series of time delay meansto said'switclt closing means, said switch closing means being energize'dfthrough a iditferent'one of said series yof time delay-means after each switch opening operation,r said disconnect plug and socket means allowing. the opening sand reclosing time delays of said opening f and reclosing means to 'be selectively changed by substi-v tuting time delay circuit means having dierent characteristics. t
, 11. The repeating circuit interrupter'setforth in claimr` 1 ,wherein said time delay circuit means is operative to:
del-ay one of saidV switch kopening operations. u
12. The repeating circuit interrupter set forthn inclaim 5*..1 ywherein said time delay circuitmeans is operative to; t
Andersen Dec. 9, 19,30 Edsall May 12, 1931