摘要:
Emergency lighting system with alarm for fire, gas and ambient air pollution with automatic monitoring and battery recharging utilizing a bus and a microprocessor circuit whose input and output signals regulate the programming. A sensor for one or more environmental hazard factors is connected to the data bus.
摘要:
A supervisory circuit for use with an audio intrusion detection system is disclosed. The supervisory circuit periodically generates an audio test signal which is supplied to a sounder which emits an audio test sound. The audio test sound is directed into a volume of space, in the same volume of space as which the audio intrusion detection system is directed to detect. The audio intrusion detection system detects the test sound and generates an audio test signal in response thereto. During the generation of the audio test sound, the comparing apparatus of the audio intrusion detection system is disabled. The audio test signal generated by the audio intrusion detection system is then compared to a test threshold signal. A test result signal is generated in response to the comparison with the test result signal indicative of the operability of the audio intrusion detection system.
摘要:
A security system provides for bidirectional communication between a controller and a plurality of addressable transponders. At least one transponder includes a sensor circuit for detecting motion, which motion is indicated by the transponder signalling back to the controller. During a walk test the controller sends a signal back to the transponder, completing the circuit for the visible output indicator so that subsequent motions during the walk test sequence will be immediately displayed at the transponder, without necessitating successive communication through the loop including the controller. In systems where the controller itself reports upwardly in a hierarchy of units, the walk test can confirm operability of the entire system, including other condition-indicating signals.
摘要:
A multizone intruder detection system comprises a supervisory circuit for verifying, while the system is disarmed, that each of a plurality of intrusion sensors is, indeed, functional. The supervisory circuit inhibits rearming of a disarmed system until it determines that each sensor has successfully operated within a relatively brief time interval just prior to the time an attempt is made to arm the system. A timing circuit, activated by a preliminary arm signal, operates to establish a time window (e.g. 10 minutes) within which the operability of each sensor must be verified (i.e. walk-tested) as a precondition to system arming. Preferably, the timing circuit is reset by each sensor alarm output, whereby the system user is given the full time window to walk-test each sensor. By virtue of the invention, sensor sabotage in a disarmed system can be mitigated.
摘要:
An infra-red remote personal alarm system consists of a portable transmitter unit (10) which is intended to be worn or to be manually carried by the user, and which is operable by the user at any particular location to transmit an alarm signal in an emergency and which is to be received by a central receiving station (41) so that appropriate action can be initiated in response thereto. The transmitter unit is electrically operable and includes means (15) for transmitting pulsed infra-red alarm signals which can be picked-up by an infra-red signal receiver at the location of the user, and then retransmitted as an oscillating electrical signal via direct wiring (38, 39, 40, 42, 43) to the central receiving station (41) as a warning signal indicative at location monitoring points (43, 44) of the location from which the emergency call has been made. By making the transmitter units capable of transmitting infra-red pulsed warning signals, and suitably designing the receiver units to recognize and to receive the pulse signals for conversion into electrical signals for onward transmission to the central control station, it is possible to obtain transmission units which are robust and reliable in operation. Test facilities are also provided to enable continuous monitoring of the operational status of the transmission units and the receiver units, so as to minimize the risk of initiated emergency action of the transmission units being undetected.
摘要:
A detection system having sending units for sending data signals representative of a condition, such as fire, smoke, intrusion, battery condition, or an emergency, to a central receiving unit. The sending units include a microcomputer which generates a pseudo-random number, waits for a number of cycle periods equal to the pseudo-random number, then activates a transmitter to send a data signal to the receiving unit. The randomized transmission prevents the synchronized clashing of transmitters.
摘要:
A simulated target for use in conjunction with detection systems using coupled transmission lines. The simulated target is positioned in the vicinity of the transmission line and the response used both to monitor system operation and to calibrate system response levels. The simulated target can be of a type having its electrical length variable under system control or can be purely passive serving to alter the stationary response profile of the system.
摘要:
A diagnostic status indicating apparatus is used with an alarm system having a plurality of normally-closed switch contacts which are opened upon occurrence of an alarm condition. Light-emitting diodes are connected across the normally-closed switch contacts at an opposite polarity to that of the current normally passing through the contacts in the operating mode. In order to diagnose the alarm-generating condition of the electrical contacts, a switch removes the operating voltage and connects a test voltage at a reverse polarity, whereupon the LED for any open circuited electrical contact is activated. The device is preferably based upon a double-pole-double-throw switch and includes indicators for a test condition and for a ground fault.
摘要:
A machine tool safety system includes an electric field generator capacitively coupled to a receptor antenna. A self-test network includes a self-test radiating antenna and a circuit arrangement operative to apply a test signal to the self-test antenna. The test signal may be of sufficient strength to induce in the receptor antenna a first excitation signal having a magnitude greater than a first predetermined threshold to verify that the safety system is operative to detect the entry of the field generator carried on an operator's person into a hazard zone proximal to the machine tool. The test signal may be of sufficient strength to induce a second excitation signal greater than a second threshold to verify that the safety system is operative to detect the entry of the field generator into an arming zone spaced from the hazard zone.
摘要:
A taut wire intrusion detection system for a fence includes a testing device adapted to be actuated from a central station to apply a mechanical force to the fence wire in order to cause it to simulate an intrusion. The system further includes a testing circuit at the central station for actuating the testing device, and an indicator at the central station which receives the signal from the detector, and thereby indicates the actual response of the detector to the mechanical force.