Alarm system having improved control of notification appliances over common power lines
First Claim
1. A method for controlling an alarm system, comprising:
- sending a message to a notification appliance having at least one audible alarm, said message comprising a drop in power forming a synchronization pulse and a command signal embedded within the synchronization pulse to control the audible alarm; and
at the notification appliance, responding as directed by said command signal.
4 Assignments
0 Petitions
Accused Products
Abstract
An alarm system which includes multiple notification appliances for signaling an alarm condition. The system controller intelligently controls the notification appliances including notification devices such as an audible or visual alarm through multi-bit digital messages sent over common communication lines. The alarm system has both a supervisory or standby mode and an active mode of operation. In the standby mode, the notification appliances are powered at a first polarity DC voltage. In an active mode of operation, the first polarity voltage is reversed (or forward biased) to energize all the notification appliances on the communication lines. The system controller controls operation of the visual alarms by issuing synchronization signals, wherein the line voltage drops to zero, which trigger the visual alarms. An audible alarm command signal is embedded within the synchronization signal to control operation of the audible alarm.
38 Citations
45 Claims
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1. A method for controlling an alarm system, comprising:
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sending a message to a notification appliance having at least one audible alarm, said message comprising a drop in power forming a synchronization pulse and a command signal embedded within the synchronization pulse to control the audible alarm; and
at the notification appliance, responding as directed by said command signal. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A notification appliance having at least one audible alarm, comprising:
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means for decoding a message comprising a synchronization pulse and a command signal embedded within the synchronization pulse; and
means for responding as directed by said command signal at said audible alarm.
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9. A notification appliance, comprising:
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at least one notification device including an audible alarm; and
an electronic circuit that decodes a message comprising a synchronization pulse and a command signal embedded within the synchronization pulse, the circuit directing operation of the audible alarm in response to the command signal. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
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20. An alarm system, comprising:
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a system controller for generating a plurality of multi-bit messages that control at least one notification appliance that includes an audible alarm;
a pair of communication lines connecting said at least one notification appliance to said system controller; and
said at least one notification appliance including an electronic circuit that receives a message comprising a synchronization pulse and a command signal embedded within the synchronization pulse, the command signal directing operation of the audible alarm. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
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31. A method for controlling a fire alarm system, comprising:
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providing a plurality of notification appliances including at least one audible alarm in a supervisory mode of operation wherein a first polarity voltage is applied to said plurality of notification appliances;
reversing the polarity of the voltage during an alarm condition such that a second polarity voltage is applied to said notification appliances; and
interrupting the second polarity voltage to the notification appliances and, during the interruption of power, transmitting a command signal to control operation of the audible alarm. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39, 40)
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41. An alarm system, comprising:
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a plurality of notification appliances, each notification appliance including at least one audible alarm and at least one visual alarm, a first polarity voltage being applied to the notification appliances in a standby mode of operation; and
a system controller that controls the audible and visual alarms, the system controller reversing the first polarity voltage during an alarm condition such that a second polarity voltage is applied to the notification appliances, the system controller interrupting the second polarity voltage to simultaneously actuate the visual alarms and, during the interruption in power, transmitting a command signal to control operation of the audible alarm. - View Dependent Claims (42, 43, 44)
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45. An alarm system, comprising:
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means for generating a plurality of multi-bit messages that control at least one notification appliance that includes an audible alarm;
means for connecting said at least one notification appliance to said generating means; and
said at least one notification appliance including means for decoding a message comprising a synchronization pulse , the command signal directing operation of audible alarm.
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Specification