US3351934A

US3351934A - Supervised alarm system

Info

Publication number: US3351934A
Application number: US456934A
Authority: US
Inventors: Norman J Vietz
Original assignee: Honeywell Inc
Current assignee: Honeywell Inc
Priority date: 1965-05-19
Filing date: 1965-05-19
Publication date: 1967-11-07
Anticipated expiration: 1984-11-07

Description

Nov. 7, 1967 N. J. VIETZ SUPERVISED ALARM SYSTEM 2 Sheets-Sheet l Filed May 19, 1965 ATTORNEY Nov. 7, 1967 N. J. VIE-rz 3,351,934

SUPERVISED ALARM SYSTEM Filed May 19, 1965 2 Sheets-Sheet 2 ATTORNEY 3,351,934 SUPERVISED ALARM SYSTEM Norman J. Vietz, Brooklyn Center, Minn., assignor to Honeywell Inc., Minneapolis, Minn., a corporation of Delaware Filed May 19, 1965, Ser. No. 456,934 9 Claims. (Cl. 340-409) ABSTRACT y F THE DISCLOSURE A direct current energized alarmsystem using a pair of conductors between a protected area and a supervised remote receiving panel. The direct current in conjunction with a polarized relay means and a polarity reversing means permits continuous supervision for faults and when necessary transmits alarms from the protected area.

The present invention is directed generally to an alarm system, and more particularly is directed to an alarm system that is capable of complete supervision of the conductors that connect a remote receiving panel to the areas protected, as well as, provide transmission of coded alarm and trouble signals. y

Alarm systems, and particularly re and similar alarm systems, have Ibecome very highly developed due to the exacting demands of the users as well as rating organizations and related groups. Due to the requirements that have developed, tire alarm systems have become very sophisticated. The systems require that a differentiation be readily made between an actual fire or alarm condition, and various faults or defects that can and do occur in the components of the systems. Further, the present day tire alarm systems require that a coding be provided so that the location of a lire or fault can be readily detected from a remote area or location. In order to accomplish all of these functions in an economical fashion, it becomes paramount that Iunusual types of circuits be developed. A further stringent requirement on systems that utilize alarms to protect areas and transmit this information back to a central or remote panel is concerned, is the utilization of a minimum number of wires. Due to the ready availability of telephone circuits, many of the systems have been developed utilizing a two conductor pair of telephone wires between the remote area where the monitoring occurs, and the protected area where the alarm or iire originates. A

The present alarm system is primarily directed to a sophisticated rlire alarm or similar type of alarm syste-m that is capable of utilizing a pair of telephone conductors between the remote area where the alarm panel is located and the protected area where the sensors or alarm generating contacts are located. The system must be capable of generating a coded alarm, thereby pin pointing the specific operator panel or location from which the alarm is emanating, as well as, a coded or noncoded trouble signal to indicate the existence of one or another different fault conditions. The fault conditions normally protected against are an open line between the remote area and the protected area, a grounding of the conductors or pair of conductors between the remote area and the protected area, a direct short circuit in the pair of conductors, or some mechanical or electrical fault in the protected area that requires correction for the system to operate in a fully normal and acceptable fashion. While a number of systems exist that will meet many of the conditions out? lined above, the systems now in existence normally are deficient in being able to supply all of the desired information over a single pair conductors and provide full supervision of coded trouble and alarm signals.

It is the primary object of the present invention to dis- United States Patent O 3,351,934 Patented Nov. 7, 196.7

ICC

close an alarm system that utilizes a single pair of conductors between a coded remote receiving panel and a protected area, and which will fully supervise the conductors against faults as well as transmit electrically separate coded trouble and coded alarm signals.

A further object of the present invention is to disclose an alarm system that utilizes conventional alarm equipment and components that are readily available and can be adapted to use in the system without great expense beyond that normally incurred in their usual installation and use.

Yet another object of the present invention is to disclose an alarm system that can transmit both coded trouble signals and coded alarm signals over a single pair of telephone conductors between the protected area and the coded remote receiving panel at a remote area.

A still further object of the present invention is to disclose an alarm system that provides complete supervision of a pair of conductors and which is capable of transmitting an alarm signal even though one of the conductors is either open circuited or grounded, and which is further not completely incapacitated even by a short circuit across the pair of conductors.

These and other objects will become apparent when the drawings are fully considered along with the following description, wherein: y

FIGURE 1 is a semi-schematic circuit of the system in its very simplest form and which is utilized to explain the invention in its rudementary form, and;

FIGURE 2 is an actual schematic of a system for commercial use and installation, and which incorporates the invention.

In the present description of FIGURES 1 and 2 the same reference numerals will be utilized in each of the figures for identification of corresponding parts. Many 'of the components are conventional electrical components and will be described or discussed in connection with the individual circuits in which they are active.v K

A description of the semi-diagrammatical arrangement of FIGURE 1 disclosing the heart of the invention will be undertaken as a preface to the detailed disclosure of FIG- URE 2. In FIGURE 1 a direct current source means 20 is connected by

conductors

21 and 22 to terminals 1 and 2 of a coded remote receiving panel generally disclosed at 23 by the dashed box or outline. Powered from terminals 1 and 2 there is disclosed. generally a relay responsive control means 24 that includes a conductor 25 connected to terminal 2 anda conductor 26 connected to a terminal 5 that is directly connected to terminal 1. It is thus obvious that

conductors

25 and 26 supply a direct current source of supply to the relay responsive control means generally disclosed at 24.

The relay responsive control means 24 incorporates a number of conventional electrical components such as resistors, capacitors, diodes, switches, relay contacts, relay coils, and associated circuitry. All of this circuitry will be described in some detail in connection with FIGURE 2, but at the present time all that need be indicated is that the relay responsive control means 24 incorporates the relay coils for a group of relays K1, K2, K3, K4, K5, K8, and a time delay relay TDR. The relay responsive control means 24 lalso incorporates a number of contacts associated with the respective relays, as well as, contacts associated with two additional relays K6 and K7 that will be located subsequently. It will -be noted that relay K1 incorporates one normally open contact K1-1. The relay K2 incorporates or operates four normally open relay contacts K2-1, K2-3, KZ-S, and K2-7. Relay K2 also operates three normally closed contacts KZ-Z, K2-4, and K2-6. The relay K3 utilizes eight contacts two of which are not shown. The contacts utilized in the present disclosure at some point are the normally closed contacts K3-2, K3-4, and K3-6, while .the relay K3 incorporates the normally open contacts K3-3 and K3-S. The relay K4 incorporates two normally open `and two normally closed contacts with contacts K4-1 and K4-3 being normally open and K4-2. and K4-4 being normally closed. The relay K5 incorporates six contacts with the contacts K5-1, K5-3, K5-5, and K5-6 being normally open while contacts K5-2 and K5-4 are normally closed. The relay K8, which is also incorporated in the relay responsive control means 24, incorporates two normally open contacts KS-l and KS-S and a single normally closed contact K8-2. The balance of the -relay function within the rellay responsive contro-l means 24 is handled by a time delay relay TDR that has a normally closed contact TDR-1 and a normally open contact TDR-2.

The various combinations of energization and function of the relays and their associated contacts and components allow the presently disclosed device to perform a large group of functions, each of which will be detailed in connection with FIGURE 2. A Ifurther description of FIGURE l at this point will clarify the broad object and embodiment of the present invention.

The four contacts of relay K4 and their associated circuitry yield a circuit polarity reversing means 30 shown in a dotted box. The circuit polarity reversing means 30 incorporates the normally closed contacts K4-2 and K4-4 and a pair of normally open contacts K4-'1 and K4-3, along withfa pair of

reversing conductors

31 and 32 to provide a reversal of the direct current source potential between the

input points

33 and 34 and the

output points

35 and 36. These contacts could be replaced by a multivibrator circuit or oscillator, if desired. The output point 35 is connected to an output terminal 3 of the coded re- `mote receiving panel 23. The point 36 `is connected to a polarized relay means generally disclosed at 40 and which is made up of a pair of series connected relays K6 and K7 that are respectively paralleled by diodes or asymmetric current conducting means CR1 and CRZ, with the diodes CRI and CRZ polarized in opposite directions. The polarized relay means 40 has an output point 41 which is connected to terminal 4 of the coded remote receiving panel 23. While the polarized relay means 40 has been disclosed as a pair of series connected relays K6 and K7 that are in turn paralleled by diodes CR1 and CRZ, the polarized relay means 40 could be any type of polarized relay that is capable of polarized operation. By that it is meant that the current passing through the polarized relay means 40 in one 'direction would operate the relay in one manner, whilecurrent passing through the relay 40 in the opposite direction would cause a reverse operation. It is further meant that with no current flowing the relay means 40 would assume a neutral position. Also the diodes could be placed in series with the relays K6 and K7 and then they could be connected in series. The simplest arrangement of this type of relay is as disclosed utilizing two conventional relays that are polarized by diodes, but the relay means 40 could be a conventional three position relay with magnetic polarizing means. Throughout the present speclcation whenever the terminology diode is utilized it is understood that the term is used in its broadest sense as an asymmetric current conducting means.

Further associated with the coded remote receiving panel 23 and directly connected to the relay responsive control means 24 is a signal means 42 connected by

appropriate conductors

43, 44, 45, and 46 to the relay responsive control means 24. The signal means 42 can be any type of audio or visual signal means such as a bell, buzzer, recorder, or register that is operated in response to the relay functions that occur in the relay responsive control means 24. The specific signal means lfunctions will be described in detail when FIGURE 2 is discussed.

The output terminals 3 and 4 of the coded remote receiving panel 23 are connected to a pair of conductors 5()` and 51 that are under constant supervision of their condition by means of the coded remote receiving panel 23. The supervised pair of

conductors

50 and 51 normally would be telephone wires or similar Qoadutors between the coded remote receiving panel 23 and a remote protected area generally disclosed by the dotted box 49 and which represents the interior of a building or any other area to which the present alarm system is applied. The

conductors

50 and 51 are connected at terminals 52 and 53 to an alarm actuated means 54 that has been generally disclosed. The alarm actuated means 54 in fact is generally an alarm actuated switching means or is sometimes referred to as an operator or transmitter panel 54. The alarm actuated means 54 contains a number of switches and components that respond in a specied manner in the case of the transmission of a trouble or alarm condition. The arrangement and function will be discussed below. Terminals 52 and 53 are -connected to

conductors

55 and 56 that pass through a pair of normally closed contacts 57 and 5S to

outlet terminals

60 and 61 for the alarm actuated means 54. Connected between

conductors

55 and 56 are the normally open contacts 62 and a diode CRS. The diode CRS is polarized so as to oppose any current llow if the potential between

conductors

55 and 56 is from plus to minus. Also connected to conductor 55 is a normally open contact 63 that is -connected to a terminal 64 that is grounded at 65.

When an alarm actuates the alarm actuated means 54 the contacts 57 and 5S open, contact 62 closes and approximately milliseconds later contact 63 closes. In the case of the transmission of a coded trouble signal alone, the contact 57 only would be operated by the alarm actuated means 54. The exact result of this operation will be discussed subsequently. Connected between

terminals

60 and 61 of the alarm actuated means 54 is a terminating impedance in the form of a diode CR7. The diode CR7 is polarized in an opposite direction to the diode CRS.

Operation of FIG URE 1 The circuit disclosed in FIGURE 1 is in its operating condition as disclosed. In this condition the pair of

conductors

50 and 51 is being supervised with no alarm condition or trouble condition existing in the protected .area 49 which encompasses the alarm actuated means 54. Under these conditions a direct current flows from source means 20 through the closed contact K4-2 over conductor 50 through the closed contact 57 and through the diode CR7 back directly to the supervised conductor 51. The supervised conductor 51 supplied this direct current flow to the polarized relay means 40 where the current passes through the diode CRZ and then passes through the relay coil K6 to energize this portion of the polarized relay means 40. The current then ilows back through the closed relay contact K44 to the direct current source means 20. With the energized relay coil K6, through its contacts K6-1 and K6-2 which are normally open and normally closed respectively (FIGURE 2), the relay responsive control means 24 senses a normal condition with current flow through the

conductors

50 and 51 and no alarm or trouble condition. This is the normal or supervised state of the device.

Should a re be detected by the alarm actuated means 54, the contacts 57 and 58 opened along with the subsequent closing of the

contacts

62 and 63. It is thus apparent that the diode CR7 is removed from the circuit and the reverse polarity diode CRS is placed in the circuit as the terminating impedance for

wires

50 and 51. Approximately 100 milliseconds later the positive side of the direct curlrent source means 20 is also grounded at 65. This grounding completes a circuit to a grounded conductor 66 of the relay responsive control means 24 if relay K6 is energized (K6-1 closed) or relay K3 is de-energized (K3-2) closed.

As soon as the diode CRS is placed across the

conductors

50 and 51, the current flow through the conductors` 50 and 51 temporarily ceases. The lack of current flow through K6 causes the relay K6 to respond by opening:

its normally open contact which causes the circuit polarity reversing means 30 to operate thereby reversing the con-- CR8 is properly polarized to carry current through the supervising pair of

conductors

50 and 51 in a reverse direction to that originally carried during normal operation without an alarm. The reversal of current flow in

conductors

50 and 51 causes the relay K6 to be bypassed through the diode CRl but pulls in the relay K7 of the polarized relay means 40. The operation of the relay K7 of the polarized relay means 40 places the relay responsive control means 24 in condition to receive an alarm signal. The alarm signal is normally coded by momentarily opening and closing the contacts 59 and 62. This opening and closing of the contacts does not allow the balance 4of the relay circuit in the relay responsive control means 24 to drop out as the contacts are open for a short enough period of time, normally four-tenths (.4) of a second. An appropriate relay (K3 in FIGURE 2) in relay responsive control means 24 has approximately a onesecond delay in drop out time thereby responding to the coding lapplied by opening and closing of the contacts 57 and 62 in the circuit to remain energized.

The present circuit also senses the presence of a coded trouble from t-he alarm actuated means 54 by operation of the contact 57 in an intermittent coded manner. The coded operation of contact 57 opens and closes the normal current ow through the relay K6 which allows the relay to operate contacts in the relay responsive control means 24 to indicate a coded trouble signal. In addition to the alarm and trouble signals from the alarm actuated means 54, the supervision of

conductors

50 and 51 protects this system against Ian open circuit, in the same fashion as intermittently opening and closing contact 57. An open circuit of conductor 50` or 51 for more than approximately one second would be a trouble signal of a continuous fault nature rather than a coded nature, thereby differentiating it rfrom a coded trouble signal being sent by the alarm actuated means 54. A grounding of the

conductors

50 or 51 or the shorting of the

conductors

50 and 51 can also be sensed by the relay responsive control means 24 due to the nature of the current flows of the two directions or the polarized directions by means of the polarized relay means 40. This will be brought out in detail in connection with the description of the device disclosed in FIGURE 2.

At this point a brief statement of the heart of the present invention is believed in order. It is obvious that a direct current energizing means 20 is supplied to a coded remote receiving panel 23 that has a circuit polarity reversing means 30 that is connected by a pair of supervised conductors through a terminating impedance CR7 in series with a polarized relay means 40. The type of current ow, both as to polarity and uniformity is sensed by this arrangement and the proper control is then obtained by the relay responsive control means 24 along with Vthe polarized relay means 40 to indicate either a trouble signal, an alarm signal, or some fault on the supervised pair of

conductors

50 and 51. This is all accomplished by the use of terminating diodes that are appropriately reversed along with the circuit polarity reversing means 30 and the polarized relay means 40 to sense the condition of the system.

A complete alarm system has been disclosed in detail in the schematic of FIGURE 2. Many of the relays, relay contacts, diodes, and other circuit components have been enumerated in connection with the description of FIGURE l and the same reference numerals will apply to both of these figures. The elements contained in the circuit of FIGURE 2 that have not yet been described in detail are conventional electrical components such as switches, diodes, capacitors, and resistors. The individual components that have not been enumerated to this point in the description will be specilically recited when their function is utilized in the following detailed description of operation of this circuit in its various modes, both normal and abnormal.

FIGURE Z-Normal circuit operation Supervisory circuits-The direct current source means 20 is connected to terminals 1 and 2 and the diode CR7 is connected across the pair of conductors or receiving

lines

50 and 51 which is ultimately connected between the terminals 3 and 4. Under these conditions, the coded remote receiving panel 23 will assume its normal supervisory condition. The conductors 50 and 51 (shown in FIGURE 2 in two sections) may be connected to any number of alarm actuated means or operator panels 54, within some fixed limits of the resistance of the

lines

50 and 51.

A supervisory circuit exists from terminal 1 by means of conductor 26 through relay K3, contact K2-4, conductor 25, terminal 2, and back to the direct current source means 20. During a normal supervisory condition, relay K3 is energized which causes the contact K3-4 to open and contact K3-3 to close, thereby completing the supervisory loop between the terminals 3 and 4. Under these conditions, a supervisory circuit exists from the direct current source means 20 by means of terminal 1, a resistor R1, contact K4-2, contact K3-3, terminal 3, conductor 50, the trouble contact 57, to a series noninterfering contact 70 (which will be described shortly) to the end of the line diode CR7 through any number of alarm actuated means 54, back through contact 58 and conductor 51 to terminal 4. The normal supervisory circuit lfurther is completed by diode CR2, the relay K6, contact K4-4 and terminal 2 back to conductor 22 from the direct current source means 20. It is thus apparent that a complete series circuit carrying current under normal supervisory conditions exists. As was previously stated, a series non-interfering contact 70 was mentioned. vThe Contact 70 along with the previously mentioned contact 58 and a contact 71 and diode CR9 complete a normally utilized contact arrangement referred to as a Yseries non-interfering contact. In the alarm art, a series non-interfering contact arrangement is a contact arrangement that when operated, terminates the alarm actuated means 54 in a fashion as if it were the last alarm actuated means in the entire series. In eiect, when the 'alarm actuated means 54 operates, contacts 70 and 58 open with contact 71 then closing. This places an end of the line diode. 'CR9 in the circuit to replace the diode CR7 ,as if the diode CR9 was the linal terminating impedance. This is a standard alarm. technique and is used to isolate the location of a trouble or alarm signal. This will be brought out in more detail in the description, as the description of the operation of various modes is completed.

With the supervisory circuit just described, the current ow through the loop or circuit is sufficient to energize the relay K6 but the voltage drop across the diode CR?. is insufficient to pull in the relay K7. When power is ap# plied, there is a possibility that relay K2 could pull in before the relays K3 and K6, because of the series connection to relay K2 through the contact K6-2. In that case, the operation would be indicated by a trouble buzzer 75 operating in the signal means 42 due to the premature operation of the relay K2 with either contact K2-6 or KZ-S and a trouble silence switch 74 having contacts S2-1 and S2-2. The trouble silence switch 74 is connected in series with a terminal 6 and the trouble buzzer 75 across

conductors

25 and 26 from the direct current source means 20. In the case of the premature operation of relay K2, the trouble buzzer 75 will sound, a trouble light DS2 which is connected by contact K2-3 across the direct current source means 20 would light, and relay K4 would be energized along with the relay K2. This condition can be readily corrected at startup by the operation yof a manual reset switch S3-1 which is placed around the contact K2-4 and in series with the relay K3 for energizing the relay K3 for reset purposes. By pushing the reset switch S3-1, the relay K3 is energized and the energization of this relay will in turn cause relay K6 to energize if the alarm lines 50 and 51 are in a normal condition. When relay K6 energizes, relay K2 will de-energize due to the opening of the normally closed contact K6-2. At this time the trouble buzzer 75 will become silent and the trouble light DS2 will go out. At this point the circuit is in normal supervisory condition with the current -ow in the

conductors

50 and 51 through the terminating diode CR7.

Trouble signals.-A trouble signal arriving at the coded remote receiving panel 23 may be a non-coded or continuous fault signal or a coded signal, depending on the type of trouble and its location. A continuous fault trouble signal can be caused by an

open alarm line

50 or 51, or a suiciently long (more than one second) opening of contact 57 of the alarm actuated means 54. When an open line occurs, relay K6 de-energizes. When relay K6 de-energizes, relay K2 energizes through contact K6-2 to cause the trouble light DS2 to be turned on along with the sounding of the trouble buzzer 75 in the signal means 42. The relay K3 is also de-energized by the operation of relay K2 if the trouble condition exists for more than approximately one second. This one second delay is created by the capacitor C2 and the resistor R3 which forms an RC network around the relay K3 to keep it energized for the one second. This one second delay is utilized to prevent momentary power disruptions from signalling a trouble on the system. When relay K3 drops out, contact K36 connects the conductor 25 through contact K8-2 to the time delay relay TDR. Contact K3-6 also causes the energization of relay K4 through the diode CR6. The operation of relay K4 is a critical operation in the present device as it in turn operates the circuit polarity reversing means 30 that encompasses the contacts K41, K4-2, K4-3, and K4-4. The operation of relay K4 and the circuit polarity reversing means 30 changes the polarity of the voltage available to the relay K7.

About ten seconds after energization, the time delay TDR will cause its Contact TDR-1 to open. After about one minute of the supplying of power to the time delay relay TDR, contact TDR-2 will close causing relay KS to be pulled in and relay K8 will lock itself in through its own contact K81. At the same time, contact K8-2 takes power ot the time delay relay TDR. When relay K8 makes, contact K8-3 is in series with the time delay relay contact TDR-1 which again closes in about ive minutes and relay K3 is energized. When the relay K3 energizes, Contact K3-3 closes, contact K3-4 opens, contact K3-6 opens and this sequence restores the alarm line circuitry to the normal condition and de-energizes relay K8. K3 is delayed in dropout by the diode CRS in parallel with K8. If at this time the alarm line has been restored to a normal condition, the relay K6 will energize causing the relay K2 to drop out and relay K3 to remain energized, and the coded remote receiving panel 23 will be returned to normal. It the alarm line has not been returned to its normal condition, relay K6 will not pull in and the relay K3 will de-energize about one second after relay K8 has de-energized. The above described action is called the automatic reset action of the coded remote receiving panel 23. The time delay relay will complete a heating-cooling cycle approximately every five minutes until the panel is reset. This arrangement provides for complete reset of the device when the trouble that has started the sequence has been removed.

A coded trouble signal is received from a coded trouble contact arrangement contained in the alarm actuated means 54. The coded trouble contact arrangement is the contact 57 as disclosed in the alarm actuated means 54. The alarm actuated means 54 has a pair of series noninterfering contacts 70 and 5S which open and place the diode CR9 in series with the trouble contact 57 to eliminate any possibility of receiving a jumbled code from any unit further down the

lines

50 and 51. When the coded signal contact 57 opens, the relay K6 drops out causing the relay K2 to energize and the relay K4 to reverse the polarity of the lines to terminals 3 and 4 for about 25 milliseconds. When relays K2 energizes, the trouble light DS2 operates along with the trouble buzzer 75. When the trouble contact 57 in the operator panel returns to the normal or closed position, relay K6 energizes again to cause relay K2 to de-energize and the trouble light DS2 and the buzzer 75 are silenced. This same sequence will recur for every opening and closing of the trouble contact 57 in the alarm actuated means 54. By operating the trouble contact 57 in a particularly coded sequence depending on which alarm actuated means 54 is operated, a coded trouble signal is developed. It should be noted, that the relay K3 does not drop out for about one second after contact K2-4 opens, so that for a normal coded round or sequence of signals, relay K3 will remain energized. When the alarm actuated means 54 panel is through with the coded trouble signal, the receiving line is returned to normal andthe coded remote receiving panel 23 automatically returns to its normal condition.

In the present arrangement a normal code is approximately 0.4 second on and 0.4 second oth When an alarm actuated means 54 goes into a continuous fault trouble condition or the alarm line opens, the trouble buzzer 75 may be silenced by moving the trouble switch 74 from position S2-2 to S21. This trouble silence switch has a ring-back feature built-in so that when the panel is reset manually or automatically, the buzzer will sound if the panel is in a normal position, but the trouble silence switch is in an olf-normal position.

Alarm signal.-Before describing the coded action at the remote receiving panel 23 for an alarm signal, the coding action of the operator panel or alarm actuated means 54 will be described. An alarm signal is transmitted from the V alarm actuated means or operator panel 54 with the series non-interferring contacts 58 and 70 opening the connection to all circuits electrically further from the alarm actuated means or operator panel 54, and closing a contact 71 in series with a diode CR9 that forms the terminating impedance for the circuit at that point. This part of the alarm signalling action does not effect any action of the coded remote receiving panel 23 because the relay K3 will tolerate a one second open circuit in the line before it operates. The alarm coding action begins with the trouble contact 57 opening and the normally open alarm contact 62 in series with the diode CRS closing. The time between the yopening of the trouble contact 57 and the closing of the alarm Contact 62 in series with the diode CRS is in the order of a few milliseconds. The normally open contact 63 to the ground closes approximately 100 milliseconds after the normal open alarm contact 62 in series with the diode CRS has closed.

The alarm signal arriving at the coded remote receiving panel 23 will code the trouble buzzer 75 and light DS2 along with the operation of an alarm bell or hom 76 and the alarm light DS1. The trouble contact at the operator panel or alarm actuated means 54 in opening causes relay K6 to de-energize which .causes the relay K2 to energize. When relay K2 energizes, the trouble light DS2 and the trouble buzzer 75 sound, along with operation of the contact K2-1 which causes the relay K4 to energize during the RC time of the capacitor C3 and R4 thereby operating the circuit polarity reversing means 30. When the alarm contact 62 in series with the diode CRS in the alarm actuated means 54 closes, relay K7 energizes due to the reversal of polarity caused by the operation of the circuit polarity reversing means 30 under the action of relay K4. When the relay K7 energizes, relay contacts K7-1 cause the relay K5 to energize. The operation of relay K5 in turn causes the alarm horn or bell 76 to sound, the alarm lights DS2 to light, and contact KS-S to operate which causes relay K4 to keep the line polarity reversed, thereby holding the relay K7 in an energized condition. When the operator panel or alarm actuated means 54 has contact 63 closed to ground, there would be no further action at the coded remote receiving panel 23 at this time because the coded remote receiving panel 23 is in a normal operating condition.

When the alarm actuated means 54 opens the ground contact 63, there will be no panel operation. When the alarm contact 62 in series with the diode CR8 opens, relay K7 will de-energize. The de-energization of relay K7 causes relay K to de-energize causing the relay K4 to deenergize. This action also turns the alarm horn or bell 76 oil and extinguishes the alarm lamp DS1. When the alarm actuated means 54 or trouble contacts 57 close, the relay K6 is energized causing the relay K2 to deenergize, which turns the alarm light DS1 off and silences the trouble buzzer 7S. This action is repeated over and over again for all alarm codes. It should be pointed out that relay K3 does not de-energize during the time because of its holding action caused by the RC network formed by the capacitor C2 and the resistor R3.

Abnormal circuit operation Abnormal circuit operation occurs when an operator panel or alarm actuated means 54 tries to transmit or send lsignals with a single line fault. A line fault is considered to be an open line, a grounded line, or a shorted line. Explicitly, a shorted line means a short circuit somewhere between the terminals 3 and 4 and the end of the line diode CR7.

Supervisory crcuts.-The receiving panel 23 will have a supervisory circuit for an open line, a grounded line, or a shorted line. When referring to a supervisory circuit, it is meant that either a circuit will exist or will not exist but that the coded remote receiving panel 23 will respond to these conditions. When an open line occurs, relay K6 will drop out which causes relay K2 to energize, and the trouble buzzer 75 and trouble light DS2 will be operated. Approximately one second later K3 drops out. This action, as pointed out before, starts the automatic reset feature of the receiving panel 23. During the open line condition, the alarm line is not supervised, but is able to transmit an alarm signal, as will be noted later.

When a ground occurs on an alarm receiving line such as

conductors

50 or 51, relay K1 is energized from the positive side of the direct current source 20 through a ground connection to terminal G, through the relay coil K1 itself, through a parallel arrangement of a capacitor C1 and a resistor R2 and a diode CR4 through the relay contact K6-1 to the negative side of the direct current source means 2t). When the relay K1 energizes, contact K1-1 energizes the relay K2. Contact K2*1 closes causing the relay K4 to momentarily operate the circuit Polarity reversing means 30 to reverse the polarity of the alarm line which in turn causes the relay K6 to be de-energized. When the relay K6 is .de-energized, contact K6-1 opens causing the relay K1 to be de-energized which in turn causes the relay K2 to be de-energized. At this point the whole cycle starts over again with the relay K1 energizing through the capacitor C1 and contact K6-1 which is once again closed. The only difference is that there is a slight charge on the capacitor C1. The capacitor C1 continues to charge with each round or relay energizing and deenergizing until a point is reached where relay K1 will not energize again. The end result is that the direct current source means 20 is placed across the capacitor C1 and relay K1 is de-energized. During the time that the relay K1 is energizing and de-energizing, the trouble light DS2 and the trouble buzzer 75 are pulsing on and off through the action of the relay K2. It takes approximately two seconds for the capacitors C1 to charge, but K1 operates for about 0.4 second.

If the alarm line connected to terminals 3 and 4 is shorted, there will be no indication. A short circuit between the

lines

50 and 51 will not interfere with the reception of a coded alarm signal, but eliminates the alarm line supervised circuit. As long as the coded remote receiving panel 23 is capable of receiving a coded alarm with a shorted pair of conductors, the alarm system is an acceptable system since it provides the necessary protection even though a fault does in fact exist.

Trouble signals.-A trouble signal (coded), may or may not be transmitted during a fault condition depending on the type of fault and the place on the line that the fault occurs. The receiving panel 23 will not receive a coded trouble signal from an operator panel or alarm actuated means 54 if there is an open line between the receiving panel 23 and any'alarm actuated means 54 that attempts to send a coded trouble signal. The open line will be indicated at the receiving panel as a continuous fault trouble signal.

A grounded line will not affect in any way the transmission of a coded trouble signal. The receiving panel 23 will not receive a coded or continuous fault trouble signal if there is a short across the line 5t) and 51 between the receiving panel 23 and the operator panel or alarm actuated means 54 attempting to send a coded or continuous fault trouble signal. A short across the line that is electrically further away from the receiving panel than the alarm actuated means 54 or operating panel attempting to send a code will not disrupt the trouble signal.

Alarm sgnals.--The receiving panel 23 will receive a coded alarm signal for any single fault; open line, grounded line, or shorted line. The receiving panel receives a coded alarm signal for an open in the alarm lines 50 or 51. When an open occurs, relay K6 drops out, relay K2 pulls in with relay K3 dropping out after one second and relay K4 pulling in. At this point, the receiving panel Z3 is in emergency signal receiving condition. As was pointed out before, the automatic reset feature has been actuated. In the emergency signalling condition, relay lK3 has dropped out and relay K4 has pulled in causing both sides of the alarm line to connect to the positive side of the direct current source means 20. The series noninterferring contacts 58, 7G, and 71 will operate as mentioned before. The coded trouble contact portion 57 of the alarm signalling contacts will have no efrect during the emergency signalling condition. The alarm contact in series with the diode CRS closes and approximately milliseconds later the alarm contact 63 to ground closes, causing the relay K7 to energize. The circuit for energizing the relay K7 originates at the positive side of the direct current source means 20 and continues through the resistance R1, contact K4-1, diode CRI, relay K7, to terminal 4. For this point there is a parallel path down through the alarm line to the alarm actuated means or operator panel 54. Of course, the open line could occur in one of these two paths but the positive voltage will still reach the alarm contact that shorts to ground by the unbroken conductor. Because relay K3 has de-energized, contact K3-2 connects the negative side of the direct current source means 20 to ground thus completing a circuit to the alarm grounding contacts 63 of the alarm actuated means S4.

The receiving panel 23 receives alarm signals in the normal manner when there is a single ground fault on the alarm receiving lines 5t) or 51. As explained previously, when the ground occurs, there is a short rapid pulsing of the trouble light DS2 and the trouble bell or buzzer 75 will operate due to the operation of relays K1, K2, K4, and K6. Also, the receiving panel 23 will operate with a short across the line. A short across the line will not be detected at the time it occurs. When there is a short across the alarm lines 50 and 51 between the receiving panel 23 and the alarm actuated means 54, and the means 54 is sending a coded alarm signal, the receiving panel 23 is switched to the emergency operating condition by the operation of relay K1. When the operator alarm contacts make to ground, including the

contacts

62 and 63, relay K1 energizes causing relay K2 to energize. When K2 energizes, contact K2-1 causes relay K4 to give a pulsing ll i reversal of polarity to the relays K6 and K7 by the operation of the circuit polarity reversing means 30. This reversed polarity pulse is of sufficient duration to cause the relay K6 to de-energize and relay K7 to energize because relay K3 is still energized. When relay K7 energizes, contacts K7-1 energize relay K5 causing contacts KS-S to close and hold relay K4 in an energized state. Actually, the time between contacts KZ-l pulling in relay K4 and the closure of contacts KS-S is shorter than the pulse duration caused by the capacitors C3 and the resistance R4, so relay K4 is pulled in and remains locked in through the combination of contacts, the relays K4 and KS along with relay K7 and short across the line. About one second after relay K2 energizes, K3 will drop out causing relay K7 to drop out which causes relay K5 to drop out. When relay K3 dropped out its contacts K3-6 closed to keep K4 energized so the polarity of the line will remain in the reversed condition or direction. When the alarm contact 63 closes to ground, it will pulse relay K7 which in turn will pulse relay K5 causing the alarm lamp and trouble bell 76 to indicate the alarm. The circuit for pulsing relay K7 is formed from the positive side of the direct current source means 20 through the resistor Rd, the contact K4-1, diode CRI, relay K7, and out both of teminals 3 and 4 in a parallel path down to the alarm actuated means 54 through the alarm actuated contact 63 that shorts to ground, and back to the negative side of the power supply through the ground connection 66 at terminal G and contact K3-2. It should be pointed out that the first one or two pulses of the first group or round of code will be jumbled into a one second alarm pulse during the time that relay K3 is dropping out. After an alarm has been transmitted to the receiving panel 23 over a shorted line, the receiving panel 23 cannot be reset, which is an indication that a shorted line might exist.

Provided with this equipment is a number of auxiliary contacts operated by the various relays K2, K3, and K5. These various contacts are connected Vbetween the

terminals

7, 8, 9, 10, 11, 12, 13, 14, and to provide various coding and auxiliary functions for control of equipment such as recording tapes, alarm lights and any other type of alarm equipment desired. This equipment completes the coded remote receiving panel 23 in detail.

The detailed description of the operation of various circuits in FIGURE 2 have been undertaken as a means of explaining how the invention is applied to a practical embodiment providing all of the necessary functions to meet the requirements of industry and the rating organizations that deal in alarm circuits such as fire alarms. In order to help clarify the various operations and functions two tables have been prepared that summarize various phases of the operation of the alarm system. Table I discloses the state of each of the relays during Various phases of operation of the alarm system. Table II provides a brief informal description of the function associated with each relay.

TABLE II General function of the relay The invention, however, is completely contained in the circuit contained in broader form in FIGURE 1. Since the present invention can be varied extensively depending on what functions are desired, the content of the relay responsive control means 24 can be varied to include or exclude functions depending on the complexity desired. As such, in the present application, this section of the device has been referred to broadly as the relay responsive control means and no attempt has been made to specifically dene the functions that it will perform as far as the invention is concerned. The true heart of the invention encompasses many variations of the circuitry contained in the relay responsive control means 24 and it forms no specific part of the present invention. The present invention is defined solely by the scope of the appended claims.

I claim as my invention:

1. An alarm system, comprising: direct current source means including connection means connected to alarm actuated means in series with polarized relay means; said alarm actuated means including first asymmetric current conducting means; said alarm actuated means further including alarm actuated switching means having second asymmetric current conducting means substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of said alarm actuated means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said polarized relay means; and relay responsive control means and signal means connected by said connection means to said source means and responsive to said operation of said polarized relay means to in turn operate said circuit polarity reversing means and said polarized relay means to activate said relay responsive control means to thereby operate said signal means.

2. An alarm system, comprising: direct current source 0 means including connection means connected to alarm actuated means with first relay means and further with second relay means; first diode means in circuit with said first relay means and second diode means in circuit with said second relay means; said first and second diode means being oppositely polarized to each other; said alarm actuated means including first asymmetric current conducting means; said alarm actuated means further including alarm actuated switching means having second asymmetric current conducting means substituted in place of TABLE I Circuit Condition Relay K1 K2 K3 K4 K5 K6 K7 K8 & TDR

Normal X X Continuous Trouble Signal. X X X Coded Trouble Signal X Coded Alarm X Open Line X X X Grounded Line O O O O & X Coded Alarm W/Opeu Line X X X Coded Alarm W/Grounded Line.. O O & X O & O & Coded Alarm W/Shorted Line X X X O-Pulsed for short time when round first occurs. Codingg X-Energized.

said asymmetric current conducting means in reverse polarity upon the operation of said alarm actuating means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said relay means; and relay responsive control means and signal means connected by said connection means to said source means and responsive to said operation of said first relay means to in turn operate said circuit polarity reversing means and said second relay means to activate said relay responsive control means to thereby operate said signal means.

3. An alarm system, comprising: direct current source means including connection means connected to alarm actuated means in series with polarized relay means; said connection means including a pair of conductors over which alarm signals are transmitted and which conductors are supervised; said alarm actuated means including first asymmetric current conducting means; said alarm actuated means further including alarm actuated switching means having second asymmetric current conducting means substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of said alarm actuated means; said switching means further including ground circuit means to ground said source means upon operation of said alarm actuated means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said polarized relay means; and relay responsive control means including a ground connection and signal means connected by said connection means to said source means; said relay responsive control means and said signal means responsive to the condition of said pair of conductors and said alarm actuated means.

4, An alarm system, comprising: direct current source means including connection means connected to alarm actuated means with first relay means and further with second relay means; first diode means in circuit with said first relay means and second diode means in circuit with said second relay means; said first and second diode means being oppositely polarized to e-ach other; said connection means including a pair of conductors over which alarm signals are transmitted and which conductors are supervised; said alarm actuated means including first asymmetric current conducting means; said alarm actuated means further including alarm actuated switching means having second asymmetric current conducting means substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of said alarm actuated means; said switching means further including ground circuit means to ground said source means upon operation of said alarm actuated means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said first land second relay means; and relay responsive control means including a ground connection and signal means connected by said connection means to said source means; said relay responsive control means and saidsignal means responsive to the condition of said pair of conductors and said alarm actuated means depending upon the energization of said relay means.

5. An alarm system, comprising: direct current source means including connection means connected to alarm actuated switching means in series with first relay means and further in series with second relay means; first diode means in parallel circuit with said first relay means and second diode means in parallel'circuit with said second relay means; said first and second diode means being oppositely polarized to each other; said connection means including a pair of conductors over which alarm signals are transmitted and which pair of conductors are supervised; first asymmetric current conducting means connected in parallel circuit with said alarm actuated switching means; `said alarm actuated switching means further including alarm actuated contact means having second asymmetric current conducting means substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of said contact means; said contact means further including a grounded contact to ground one side of said source means upon operation of said contact means; circuit polarity reversing contacts including said connection means connected to said source means to reversibly power said alarm actuated switching means and said first and second relay means; and relay responsive control means including a ground connection and signal means connected by said connection means to said source means; said relay responsive control means and said signal means responsive to the condition of said pair of conductors and said alarm actuated switching means depending upon the energization of said relay means.

6. An alarm system, comprising: direct current source means including connection means connected through a plurality of alarm actuated means in series circuit with polarized relay means; first asymmetric current conducting means connected in parallel circuit with one of said alarm actuated means which is electrically most remote from said source means; each of said alarm actuated means further including alarm actuated switching means having second asymmetric current .conducting means which can be substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of one of `said alarm actuated means; circuit polarity reversing means including said connection means connected to said so-urce means to reversibly power said plurality of alarm actuated means and said polarized relay means; and relay responsive control means and lsignal means connected by said connection means to said source means and responsive to said operation of said polarized relay means to in turn operate said circuit polarity reversing means and said polarized relay means to activate said relay responsive control means to thereby operate said signal means.

7. An alarm system, comprising: direct current source means including connection means connected through a plurality of alarm actuated means with first relay means and further with second relay means; first diode means in circuit with said rst relay means and second diode means in circuit with said second relay means; said first and second diode means being oppositely polarized to each other; first asymmetric current conducting means connected in parallel circuit with one of said alarm actuated means which is electrically most remote from said source means; each of said alarm actuated means further including alarm actuated switching means having second asymmetric current conducting means substituted in place of said first asymmetric current conducting means in reverse polarity upon the operation of one of, said alarm actuated means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said relay means; and relay responsive control means and signal means connected by said connection means to said source means and responsive to said operation of said first relay means to in turn operate said circuit polarity reversing means and said second relay means to activate said relay responsive control means to thereby operate said signal means.

8. An alarm system, comprising: direct current source means including connection means connected through a plurality of alarm-actuated means in series with polarized relay means; said connection means including a pair of conductors over which alarm signals are transmitted with said pair of conductors connected in series with said alarm actuated means; first asymmetric current conducting means connected in parallel circuit with one of said alarm actuated means as a termination for said pair of conductors; each of said alarm actuated means further including alarm Iactuated switching means having second asymmetric current conducting means substituted in place of said rst asymmetric current conducting means in reverse polarity upon the operation of one of said alarm actuated means as a termination for said pair of conductors; each of said switching means further including ground circ-uit means to ground said source means upon operation of one of said alarm actuated means; circuit polarity reversing means including said connection means connected to said source means to reversibly power said alarm actuated means and said polarized relay means; and relay responsive control means including a ground connection and signal means connected by said connection means to said source means; said relay responsive control means and said signal means responsive to the condition of said pair of -cond-uctors and said alarm actuated means.

9. An alarm system, comprising: direct -current source means including connection means connected through a plurality of alarm actuated means in series circuit with tirst relay means and further in series with second relay means; first diode means in parallel circuit with said rst relay means and second diode means in parallel circuit with said second relay mean-s; said irst and second diode means being oppositely polarized to each other; said connection means including a pair of conductors over which alarm signals are transmitted and which is connected in series with said plurality of alarm actuated means; rst

asymmetric current conducting means connected in parallel lcircuit with one of said alarm actuated means which is electrically most remote from said source means; each of said alarm actuated means further including alarm actuated `switching means having second asymmetric current conducting means substituted in place of said rst asymmetric current conducting means in reverse polarity upon the operation of one of said alarm actuated means;

each of said switching means further including ground No references cited.

THOMAS B. HABECKER, Primary Examiner.

D. L. TRAFTON, Assistant Examiner.

Claims

1. AN ALARM SYSTEM, COMPRISING: DIRECT CURRENT SOURCE MEANS INCLUDING CONNECTION MEANS CONNECTED TO ALARM ACTUATED MEANS IN SERIES WITH POLARIZED RELAY MEANS; SAID ALARM ACTUATED MEANS INCLUDING FIRST ASYMMETRIC CURRENT CONDUCTING MEANS; SAID ALARM ACTUATED MEANS FURTHER INCLUDING ALARM ACTUATED SWITCHING MEANS HAVING SECOND ASYMMETRIC CURRENT CONDUCTING MEANS SUBSTITUTED IN PLACE OF SAID FIRST ASYMMETRIC CURRENT CONDUCTING MEANS IN REVERSE POLARITY UPON THE OPERATION OF SAID ALARM ACTUATED MEANS; CIRCUIT POLARITY REVERSING MEANS INCLUDING SAID CONNECTION MEANS CONECTED TO SAID SOURCE MEANS TO REVERSIBLY POWER SAID ALARM ACTUATED MEANS AND SAID POLARIZED RELAY MEANS; AND RELAY RESPONSIVE CONTROL MEANS AN SIGNAL MEANS CONNECTED BY SAID CONNECTION MEANS TO SAID SOURCE MEANS AND RESPONSIVE TO SAID OPERATION OF SAID POLARIZED RELAY MEANS TO IN TURN OPERATE SAID CIRCUIT PORLARITY REVERSING MEANS AND SAID POLARIZED RELAY MEANS TO ACTIVATE SAID RELAY RESPONSIVE CONTROL MEANS TO THEREBY OPERATED SAID SIGNAL MEANS.