Method and apparatus for determining proper installation of alarm devices
First Claim
1. An apparatus for determining improper installation of a plurality of addressable devices coupled to a line in an alarm system, comprising:
- a poll transmission circuit coupled to the line, the poll transmission circuit polling individual addresses of the addressable devices;
a receiving circuit coupled to the line, the receiving circuit detecting a response on the line from at least one addressable device responding to a poll message generated by the poll transmission circuit;
the receiving circuit having a normal sensitivity used for sensing normal non-test communications with devices on the line and a reduced sensitivity that is lowered in relation to the normal sensitivity to detect devices improperly installed on the line, based upon a comparison of the response and the reduced sensitivity, while in a device testing mode.
4 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus detect devices on a line in an alarm system that have been assigned a common or duplicate address, or that are located beyond the maximum allowable wiring distance on the line, or that are poorly connected to the line thus providing weak answers to communications from the control panel. The method and apparatus operate by polling suspect addresses of devices on the line while adjusting the sensitivity of the receiver. The sensitivity of the receiver is lowered by an amount corresponding to the test being performed. In duplicate address testing, the sensitivity of the receiver is lowered by an amount such that a single response from only one device having the polled address will not be sensed, but combined responses from more than one device having the same address are sensed. In weak answer testing, the sensitivity of the receiver is lowered by an amount such that a single response from a device securely connected to the line and within the wiring distance limits is detected, but a device un-securely connected to the line or beyond the maximum wiring distance is not detected.
18 Citations
32 Claims
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1. An apparatus for determining improper installation of a plurality of addressable devices coupled to a line in an alarm system, comprising:
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a poll transmission circuit coupled to the line, the poll transmission circuit polling individual addresses of the addressable devices; a receiving circuit coupled to the line, the receiving circuit detecting a response on the line from at least one addressable device responding to a poll message generated by the poll transmission circuit; the receiving circuit having a normal sensitivity used for sensing normal non-test communications with devices on the line and a reduced sensitivity that is lowered in relation to the normal sensitivity to detect devices improperly installed on the line, based upon a comparison of the response and the reduced sensitivity, while in a device testing mode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A receiving circuit for detecting improper installation of addressable devices coupled to a line in an alarm system, after an address of one of the addressable devices has been polled and at least one device returns a response in response to the poll, the receiving circuit comprising:
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an input for receiving the response; a sensitivity selection circuit providing a sensitivity reference voltage that is adjustable based upon the selection of at least one test input; a comparator including; a first input which couples to the sensitivity selection circuit to receive the sensitivity reference voltage which determines the sensitivity of the comparator; a second input for receiving a measurement of the response value received at the input of the receiving circuit; and wherein, upon selection of one of the at least one test input, the sensitivity reference voltage is lowered to reduced the sensitivity of the comparator as compared to a normal sensitivity, such that a sense value is produced by the comparator if the measurement of the response value crosses a threshold of the comparator as determined by the sensitivity reference voltage. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
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20. A method for detecting improperly wired and improperly addressed devices coupled to a line in an alarm system, comprising the steps of:
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in a receiving circuit, lowering the sensitivity of sensing a response value from at least one device; polling an address of a device on the line with a poll sent from a poll transmission circuit; in the receiving circuit, receiving a response value on the line in response to the poll; and determining if a measurement of the response value crosses a threshold of the receiving circuit having the lowered sensitivity as an indication of the presence of at least one improperly installed device on the line. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
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32. An alarm system including an integrated circuit for detecting improperly wired and improperly addressed devices, comprising:
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a plurality of devices connected to a line; a control panel coupled to the line; a poll transmission circuit within the control panel coupled to the line and having a means for polling addresses of the plurality of devices; and a receiving circuit within the control panel coupled to the line and having a means for lowering a sensitivity of detecting and measuring a response value returned from at least one device on the line in response to a poll, such that while the sensitivity of the receiving circuit is lowered, if in a duplicate address testing mode and more than one response value is sensed, a duplicate address on the line is detected, and if in a weak answer testing mode and only one response value is sensed, the response value indicates a device properly wired to the line in the alarm system.
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Specification