US1298710A - Burglar-alarm system. - Google Patents

Burglar-alarm system. Download PDF

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US1298710A
US1298710A US2879215A US2879215A US1298710A US 1298710 A US1298710 A US 1298710A US 2879215 A US2879215 A US 2879215A US 2879215 A US2879215 A US 2879215A US 1298710 A US1298710 A US 1298710A
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alarm
armature
circuit
circuits
wire
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • G08B17/06Electric actuation of the alarm, e.g. using a thermally-operated switch

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  • WITNESSES INVEN TOR WITNESSES INVEN TOR.
  • This invention relates to improved electric burglaralarm systems and aims to provide asystem in which agreater degree of protection is obtained bythe use of a plurality of normally closed protectiveicircuits, such additional-protection bein due to the fact that upon the. accidental. reaking of' any one of said closed rotective circuits there will be given an armshowing'th'at that" circuit is inoperative, in which latter case the others ofsaid'clo'sed protective circuits will still j upon interference withthe protected 'struo ⁇ ture.
  • each 1 of said protective circuits containing a visible. alarm, preferably a lamp, which is, therefore, continually burning when its cir- 'cuit is intact, and each protective circuit containin one coil of ,a' pair of electro-- magnets aving' the same magnetic circuit.
  • electroimagnets are arranged nor mally to hold an armature out of engagement j with a contact in another circuit; this sec- 0nd circuit containingan audible signal as a bell.
  • the strength of the above mentioned “eleotroemagnets is so calculated that either "one produces enough magnetic flux. to hold attracted. the armature but not-enough to at ,tract it from its withdrawn position against the contact ⁇ in-the'secondary circuit.
  • This arrangement -permits the giving of a visible signal when either protective circuit is comprising a pair of 'elec'tro-magnets having broken but prevents thegiving-of an audible signal unless both circuits are broken.
  • Fig. 2 shows a type of molding intended one the windings of the said elec-' Patented Apr. 1 1919.
  • troemagnets being included in the above mentioned secondary circuit while the other is included in another circuit containin source of current supply and a switch.
  • Figure 1 is a diagrammatic view showing of connect-. 111;; t 'ereto.
  • Fig. '7 shows still anothermethod of connecting thereto.
  • Fig. 1 there is shown at 10, a resistance having contact clips 11,12 and 13 thereon.
  • the .current in rent in the winding 21" are arranged to produce in their common magnetic circuit cumulative fluxes, thus causing the armature 23 to be attractedto and held against the pole pieces 24.
  • This state-of aflairs will exist as long as current passes in, at least, one winding of the pair 21, 21,.in other words so long-as, at least, one of the protective cir'- cuits is intact, for in the event of the failure of one of such circuits current will be cut ofl from one winding of the relay 22, which cutting ofl of 'current'will not'cause thearmalture 23 tofall owing to the fact that the normal, flux produced by one of the windings of said relay 22 is sufficient to hold said armature 23 against pole pieces 24 24.
  • This circuit may be most 'convenientl; traced the cessation of current in either of the pro tective circuits, its corresponding lamp -16 or 16 will be extinguished thus giving-noticeof that'ffact.
  • These lamps-16, 16 are preferably mounted in the store-window so as to be .plainly; visible from the street. I
  • the armature 23 forms together with the contact stop 25 part of the circuit.
  • Such closure allows current from the battery 26 to flow momentarily in the secondary cir-- cuit of which electro-magnet 30is'a part thus causing said magnet to attract the arma ture 27 against the contact stops 32 and 33 thereby breaking the connection of armature 27 to stop 29 thus cutting off,current.
  • Fig. 2 there is shown a section of wire molding consisting of a wood strip 37 having on one side two longitudinal slots 38 into which may be conveniently placed the protectingwires as for instance the wires d, d
  • I In F1g. 3 is shown the ordinary one mm molding in common use consisting of a half round strip 39 having a slot 40 in its round ed surface.
  • Fig. 4 the preferable form for the contact steps 29, 32, 33 is shown. These consist each of a fiat strip 41 having a sp'ring'strip 42 screwed thereto and forming a springv fork to receive the armature contact 27.
  • Fig. .5 there is shown a method of connection of the protective circuits to the republice service mains which is similar to that y without departing from the spirit of the inshown in Fig. l but has in addition, an
  • Fig. 6 there vis shown another system similar to that shown in Fig. 5 but in this v arrangement the. terminals of the resistance 10 are (through'various other apparatus) connectedjto the two'outside wires of the service mainsf'and also the clip' 12 (Fig; 1')
  • Fig. 7 isshown an arrangement similar to that in Fig. 5,, but with the insertion of. an
  • a bur 'lar alarm the combination with a guarded structure of a visible sigan audible signaling ingtwo signals, of two protective circuits each connecting the guarded structure with one of-said signals, both of said protective circuits being connected with said audible signaling means, said visible signals being normally operative toindicate that. they apparatus is'in order and that the guarded. structure has not been tampered with, either of said signals being rendered inoperative when its protective circuit is disturbed, said audiblesignaling means being energized only when both of said protective circuits are disturbed; v I
  • each of said visible signaling means belng normally operative to indicate that the associated alarm circuit is intact and'being rendered inoperative when said alarm circuit is deenergized.
  • an alarm system the combination with; an audiblesignaling means, ofan armatureya source of current connected with said armature and with said audible signaling means, a first contact connected with said audible signaling means and associated with said armature, said audible signaling 'means' being normally deenergized,-an alarm circuit controlling said armature and adapted to actuate said armature to cofiperate with said.
  • first contact to energize said audible signalingmeans whenever said alarm circuit is denergized, and means for resetting said armature, said resettingmeans comprising a second contact associated with said armature, an electrom'agnet assoclated wlth sald armature. and a switch; said second contact,-
  • said switch,and said electromagnet being connected in series, whereby when said, switch is closed said electromagnet will be energized and-attract said armature so that it will open the circuitof said audible signaling means.
  • a signaling means an electromagnet controlling a first contact in circuit .withsaid electromagnet controlled by said electromagnet,- and a sec:
  • a signaling controlled by said electromagnet, and asecond electromagnet also controlling said first contact and'saidsecond contact.
  • an electric signaling means 'first and second electromagnets
  • a first switch for said electric signaling means a second switch for said first electromeans, an electromagnet controlling a first contact 1n c1rcu1t wlthsald means, a second contact in circuit with said electromagnet magnet, and a third switch for said.
  • second means, and a second electromagnet for electromagnet said first electromagnet being opening the circuit of said signaling means, adapted to open said second switch and close each electromagnet being adapted to close said first and third switches, and said secthe circuit of the other electromagnet and to .5 0nd electromagnet being adapted to close open its own circuit. 15 said second switch and open said first and Signed at New York in the county of third switches. New York and State of New York this 11th 16.
  • an electric sigday of May, A. D. 1915. naling means, a first electromagnet for clos- 10 ing the circuit of said electric signaling SIMON B. HESS.

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  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Alarm Systems (AREA)

Description

S. B. HESS.
BURGLAR ALARM SYSTEM.
APPLICATION FILED MAY 11, 1915.
1,298,710. Patented Apr. 1,1919.
2 SHEETS-SHEET 1.
he If g wrzvissblstj M W S. .B. HESS.
BURGLAR ALARM SYSTEM.
APPLICATION FILED MAY 11, I915.
Patented Apr. 1,1919.
2 SHEETS-SHEET 2.
WITNESSES INVEN TOR.
SIMON n. HESS, or new YORK, N. Y.
acumen-ALAR s'Ys'rnM.
To allwhom it may com-em Be it known that I, SIMON zen of'the" United States, residing n New York city, in the county of New York and State of New'York, have invented certain .new and useful Improvements in Bu'rglan Alarm Systems of which the following is a specification; I
This invention'relates to improved electric burglaralarm systems and aims to provide asystem in which agreater degree of protection is obtained bythe use of a plurality of normally closed protectiveicircuits, such additional-protection bein due to the fact that upon the. accidental. reaking of' any one of said closed rotective circuits there will be given an armshowing'th'at that" circuit is inoperative, in which latter case the others ofsaid'clo'sed protective circuits will still j upon interference withthe protected 'struo} ture.
v 1 sourceof "current supply, twin protective ."The invention consists, in detail,;of a
circuits supplied continuously thereby, each 1 of said protective circuits containing a visible. alarm, preferably a lamp, which is, therefore, continually burning when its cir- 'cuit is intact, and each protective circuit containin one coil of ,a' pair of electro-- magnets aving' the same magnetic circuit.
These electroimagnets are arranged nor mally to hold an armature out of engagement j with a contact in another circuit; this sec- 0nd circuit containingan audible signal as a bell. The strength of the above mentioned "eleotroemagnets is so calculated that either "one produces enough magnetic flux. to hold attracted. the armature but not-enough to at ,tract it from its withdrawn position against the contact{in-the'secondary circuit. This arrangement-permits the giving of a visible signal when either protective circuit is comprising a pair of 'elec'tro-magnets having broken but prevents thegiving-of an audible signal unless both circuits are broken.
There is also provided a novelarrangement separate circuits :and'an armature common to'both,
Specification of Letters Patent.
B. Hess, a citi-. j
be operative to actuate an alarm the 'rotective system installed in the show-' winc ow and door of a store. Fig. 2 shows a type of molding intended one the windings of the said elec-' Patented Apr. 1 1919.
Application filed'May 17, 1915-. Serial No. 28,792.-
troemagnets being included in the above mentioned secondary circuit while the other is included in another circuit containin source of current supply and a switch.
the use of suitable contacts on the armature theaudible signal secondary circuit is comand immediately thereafter the secondary circuit is broken again thus preventing needless Wasteof current." By the manipulation of a compound switch, the entire system may be conveniently reset.
There is also provided in' this invention certain, novel means whereby the source of supply for the closedprotective circuits may be the public service mains,thus eliminating the cost and annoyance incident to the use of batteries.
Referring now to the drawings Figure 1 is a diagrammatic view showing of connect-. 111;; t 'ereto.
Fig. '7 shows still anothermethod of connecting thereto. I
. In Fig. 1 there is shown at 10, a resistance having contact clips 11,12 and 13 thereon.
Current is caused to flow through said res stance 10 by means, of connection of its term1nalsTT to the service mains S and owing to this current flow, diiierences of p0 ten-tial are caused to exist between the vclips 11, 12 and 13, thus causing current to flow pleted when both protect ve Wires are broken in the circuitsconnected thereto. Such current 'may be considered to flow from the clip -1'1. through the wire a to the bell box 15,
through the inner lining thereof14 (thisbell box being similar to that described in my Patent N 0. 901,171, issued October 13, 1908,) passing thence by the wire I) to the 1ncandescent lamp l6 (keeping it alight), thence by wire along the edges of the glass windows X and Y andto the contact 17 on the door Z, thence through the wire olfin the molding on the door Z to contact 18, thence by wire a to switch arm .19. (The compound switch 20 of which arm 19 is'a part is here shown thrown to the left thus completing all protective circuits). From said switch arm 19 the current continues through the wire 7 to the winding 21 of the electro-magnetic re- 13 through the wire a, through the outer casing 14 ofthe bell box 15, thence through the wire 6, the lamp 16 (keeping it alight), thence by wire 0 along the edge of the window X, the window Y to the contact 17 on the door, Z; through wire 03 in themolding V 1on-the door Z to the contact 18, thence by Wiree to the winding 21 of the relay 22, thence by the common return wire 9 to clip 12, thus completing the other protective circuit; M
The .current in rent in the winding 21"are arranged to produce in their common magnetic circuit cumulative fluxes, thus causing the armature 23 to be attractedto and held against the pole pieces 24. This state-of aflairs will exist as long as current passes in, at least, one winding of the pair 21, 21,.in other words so long-as, at least, one of the protective cir'- cuits is intact, for in the event of the failure of one of such circuits current will be cut ofl from one winding of the relay 22, which cutting ofl of 'current'will not'cause thearmalture 23 tofall owing to the fact that the normal, flux produced by one of the windings of said relay 22 is sufficient to hold said armature 23 against pole pieces 24 24. On
This circuit may be most 'convenientl; traced the cessation of current in either of the pro tective circuits, its corresponding lamp -16 or 16 will be extinguished thus giving-noticeof that'ffact. These lamps-16, 16 are preferably mounted in the store-window so as to be .plainly; visible from the street. I
Now considering the secondary mentioned in the foregoing condensed description, the armature 23 forms together with the contact stop 25 part of the circuit.
from the; battery 26 through the wire it to the armature 27 of the relay 28. The normal position of said armature 2 7 is to the left against the contact stop 29; g-thus normally the circuit may be traced from the armature the winding 21 and the curcircuit 7 27 to the stop 29, through the. wire z,through the electromagnet winding 30, the wire 7" to --the stop 25, the armature 23, the switch arm 31 of the compound switch 20, thence bythe ,wire is to the battery 26 completing'the seconclary circuit.
Now when both protective circuits are terrupted as by the attempted entry of an unauthorizedperson, both windings 21, 21
of the relayv 22 are deenergized, causing the pole pieces 24, 24 to release the armature 23 and allowing it'toclose the contact between said armature and the contact point 25.,
Such closure allows current from the battery 26 to flow momentarily in the secondary cir-- cuit of which electro-magnet 30is'a part thus causing said magnet to attract the arma ture 27 against the contact stops 32 and 33 thereby breaking the connection of armature 27 to stop 29 thus cutting off,current.
from the magnet30. (It should be here stated that armaturr 27 is not. biased in either direction but remains. wherever thrown). I Current is then allowed to flow from the battery 26,.through wire it to armature 27, em 32, wire Z to the bell 34, thence by way of t e wire m back to battery 26 thus causing bell 34 to ring giving an audible alarm.
- In order-now to reset the system allthat is necessary is to repair the breaks in the protective circuits whereupon the manual throwing to the right .of the compound switch 20 resets. the relay-28. When switch 20 is in this right hand position current flows momentarily from battery 26 through wire h, arma ture 27, stop 33, winding of magnet 35, wire n, switch arm 36,wire 0, to switch arm 31, and along .wire 70 back-to battery 26 and energizing the magnet35 causes it to I pull armature 27 into its normal 'left hand position. Now returning to its normal left hand position thefco-mpound switch 20, the circuits feeding the windings 21,.21 being intact the'coils of relay 22 attract their armature 23 .and all circuits are as before interference and ready to give alarm again.-v
In Fig. 2 there is shown a section of wire molding consisting of a wood strip 37 having on one side two longitudinal slots 38 into which may be conveniently placed the protectingwires as for instance the wires d, d
in Fig. 1. I In F1g. 3 is shown the ordinary one mm molding in common use consisting of a half round strip 39 having a slot 40 in its round ed surface. I v
In Fig. 4 the preferable form for the contact steps 29, 32, 33 is shown. These consist each of a fiat strip 41 having a sp'ring'strip 42 screwed thereto and forming a springv fork to receive the armature contact 27.
In Fig. .5 there is shown a method of connection of the protective circuits to the publie service mains which is similar to that y without departing from the spirit of the inshown in Fig. l but has in addition, an
' electro-magnetic breaking device intended to three-wire standard type.
break the circuit containing the resistance 10 whenever a disturbance of the current n This efiect 1s relay having its windings arranged to oppose one another. In the service. means which are shown as of the From the main -S two taps, 43 and 44 are taken (44 from the I. the resistance R,
neutral main and 43 from either outside =main) the tap 43 leading to a pair of 011'- cu1ts in shunt, one of said clrcuits containing he relay'coil C, the wire 45 and the tap'wire-44, and the other containthe resistance R,
W (normally engaging the armature 47), the
the rheostat resistance coil C, the-wire 48,
armature 47, the relay 1O andthe tap wire With this arrangement of circuits, in
.the event of a disturbance of the balance of current in the two above described circuits, if such disturbance consists of apredominance of currentin coil .0 over that in coil C, or vice versa, armature 47 .-will be withdrawn from stop 46, thus breaking the circuit containing the rheostat 1Q, thereby cut.-
both protective wires ting ofi current from a and a and causing "the alarm apparatus to operate as hereinbefore described.
In Fig. 6 there vis shown another system similar to that shown in Fig. 5 but in this v arrangement the. terminals of the resistance 10 are (through'various other apparatus) connectedjto the two'outside wires of the service mainsf'and also the clip' 12 (Fig; 1')
I is' dispensed with; the wire .9 being here grounded and thus effectively connected to the'neutral wire of the three wire mains. There is,
lamp 52 showing when current is being supplied to the resistance 10 and .furthermore there is provlded anaudible alarm circuit when armature 47 is displaced and also a ture in its displaced position. tion of this arrangement is similar to that of the arrangement. shown in Fig. 5.
In Fig. 7 isshown an arrangement similar to that in Fig. 5,, but with the insertion of. an
.extra pair 01" contacts 49,50 in the wire 44;
51' being a contact plate mounted on the armature 47 and- 49 and '50 being, stop con- .tacts intended to cooperate therewith. This arrangement has .the effect. that upon a dis turbanceof current in either of the coils C and C vibration of the armature takes place lamps.16,16.'
and consequently;
flickering of the signal It will obviously be evident to one skilled in the art that various changes may be made in thescheme'of wiring herein disclosed, as
the use of a doubly wound gure S indicates the the contact stop 46 sistance connected between two two alarm circuits connected to sald naling' means and means, said visible signaling means comprisin addition, provided a tell tale lock 54 to hold said arma- The operawell as-in the arrangement of the switches,
1.- In an alarm system, the combination with public service electric mains, of a resistance connected between two of said mains, alarm circuits connected to said res'istance visible signaling means in said alarm circuits normally operative to indicate that the alarm circuits are intact, each vis1- .ble signaling means being rendered inoperative when its alarm circuit is tampered with, and audible signali means adapted tobe energized when said a arm circuits are denergized.
"2. In an alarm systeni, with public service electricfmains, of a reof said mains, resistance, separate visible signaling means in each alarm circuit, each normally operative to indicate that its alarm circuit 1s intact, each visible signaling means being rendered inoperative when its alarm circuit is tampered with, and audible signaling means adapted to be energized when both said alarm circuits are denergized. I
3.111 a bur 'lar alarm, the combination with a guarded structure of a visible sigan audible signaling ingtwo signals, of two protective circuits each connecting the guarded structure with one of-said signals, both of said protective circuits being connected with said audible signaling means, said visible signals being normally operative toindicate that. they apparatus is'in order and that the guarded. structure has not been tampered with, either of said signals being rendered inoperative when its protective circuit is disturbed, said audiblesignaling means being energized only when both of said protective circuits are disturbed; v I
4. In an alarm system, the combination with a visible signaling means and an audible signaling means, of a source of current for the. visible signaling means, two alarm circuits connecting said visible signalingmeanswith said source of current, an electromagnet having two windings, one opera tively connected in each circuit, an armature attracted by said magnet when said .windings are energized, a second armature, a second source otcurrent connected with said first and second armatures and with said audible signaling means, a first contact connected with said audible signaling means the combmation Y i and cooperating with said second armature .to energize said audible signaling means, a second contact cooperating with said first named armature, a third contact coiiperating with said" second armature and connected 'with said second contact, a second electromagnet associated with said second armature and connected'in series with said second and third contacts, whereby when said first named armature is retractedsaid second electromagnet will. be energized and attract said I second armature so that it will open the circuit of said second electromagnet and con- .nect with said first contact to energize said 15 audible signaling means.
1 5.v In an alarm system, the combination with two alarm circuits of two visible signaling means, each associated with a separate one of said alarm circuits, each of said visible signaling means belng normally operative to indicate that the associated alarm circuit is intact and'being rendered inoperative when said alarm circuit is deenergized.
6. In analarm system, the combination with two alarm circuits of two visible signalingmeans, each associated with a separate one-of said alarm circuits, and an audible signaling means, each of said visible signaling means being normally operative to in;
dicate .that the associated alarm circuit is intact and being rendered inoperative when said alarm circuit is denergized, and said audible signaling means being energized when both alarm circuits are denergized.
1'7. In; an alarm system, the combination with; an audiblesignaling means, ofan armatureya source of current connected with said armature and with said audible signaling means, a first contact connected with said audible signaling means and associated with said armature, said audible signaling 'means' being normally deenergized,-an alarm circuit controlling said armature and adapted to actuate said armature to cofiperate with said. first contact to energize said audible signalingmeans whenever said alarm circuit is denergized, and means for resetting said armature, said resettingmeans comprising a second contact associated with said armature, an electrom'agnet assoclated wlth sald armature. and a switch; said second contact,-
said switch,and said electromagnet being connected in series, whereby when said, switch is closed said electromagnet will be energized and-attract said armature so that it will open the circuitof said audible signaling means.
' '8. In an alarm system, the combination with public service electric, mains, of a resistance connected between two of said mains, alarm circuits connected to intermediate points in 'said' resistance, visible" signaling means in saidalarm circuits normally operativefto indicate that the alarm that its alarm circuit is intact, each visible 'slgnallng means belng rendered lnoperative when its alarm circuit 1s tampered with, and audible signaling means adapted to be energized when both said alarm circuits are deenergized. r 10. In an alarm system,.the combination with an alarm signaling means, an alarm circuitcontrolling said means and adapted to trip said means to cause a continuous alarm whenever said alarm circuit isideenergized, and means for resetting said alarm signaling means, said resetting means comprising an armature associated with said alarm signaling means, an electromagand said switch.
11. In an alarm system, the combination with an alarm signaling means, an alarm.
net therefor, a switch, and a circuit for said electromagnet controlled by said I armature circuit controlling said means and adapted to trip said means to cause a continuous alarm, and means "for resetting said alarm signaling means, said resetting means comprising ,an armature associated with ,said alarm signaling means, an Ielectromagnet therefor, a switch, and -a-circ uit for said electromagnet controlled by said armature and said switch.
12. In an alarmsyste'm, the combination with two alarm circuits of an alarm signals lng means,"v said alarm signaling means being energized only when both alarm 'circuits are tampered with. c
13. In an electric. system, a signaling means, an electromagnet controlling a first contact in circuit .withsaid electromagnet controlled by said electromagnet,- and a sec:
contact in circuit withsaid means, a second ond electromagnet also controlling said 'first contact.
14. In an electric system, a signaling controlled by said electromagnet, and asecond electromagnet also controlling said first contact and'saidsecond contact.
15. In an alarm system, an electric signaling means,'first and second electromagnets,
a first switch for said electric signaling means, a second switch for said first electromeans, an electromagnet controlling a first contact 1n c1rcu1t wlthsald means, a second contact in circuit with said electromagnet magnet, and a third switch for said. second means, and a second electromagnet for electromagnet, said first electromagnet being opening the circuit of said signaling means, adapted to open said second switch and close each electromagnet being adapted to close said first and third switches, and said secthe circuit of the other electromagnet and to .5 0nd electromagnet being adapted to close open its own circuit. 15 said second switch and open said first and Signed at New York in the county of third switches. New York and State of New York this 11th 16. In an alarm system, an electric sigday of May, A. D. 1915. naling means, a first electromagnet for clos- 10 ing the circuit of said electric signaling SIMON B. HESS.
US2879215A 1915-05-17 1915-05-17 Burglar-alarm system. Expired - Lifetime US1298710A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3333186A (en) * 1964-08-14 1967-07-25 Burroughs Corp Apparatus having a plurality of pairs of impedance elements for testing electrical wiring connections
US4117463A (en) * 1976-07-28 1978-09-26 Westinghouse Brake & Signal Co. Ltd. Circuit fault detection apparatus for railroad track circuit redundant connections

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3333186A (en) * 1964-08-14 1967-07-25 Burroughs Corp Apparatus having a plurality of pairs of impedance elements for testing electrical wiring connections
US4117463A (en) * 1976-07-28 1978-09-26 Westinghouse Brake & Signal Co. Ltd. Circuit fault detection apparatus for railroad track circuit redundant connections

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