Automatic addressing for fire loop

1. A method of addressing a plurality of remote units electrically connected to a fire panel in a fire loop, the method comprising:

(1) requesting an initial identifier from each remote unit;

(2) for each remote unit which responds with a unique initial identifier:

(a) assigning a unique address to the remote unit; and

(b) silencing the response of the configured remote unit to further identifier requests;

(3) for each remote unit which responds with an initial identifier matching the initial identifier of at least one other remote unit:

(a) initialising an identifier array with the initial identifier for the remote unit in question;

(b) requesting a further identifier and adding it to the identifier array for the remote unit;

(c) for each remote unit which responds with a unique identifier array:

(i) assigning a unique address to the remote unit; and

(ii) silencing the response of the configured remote unit to further identifier requests;

(d) for each remote unit which responds with an identifier array matching the identifier array of at least one other remote unit, repeating steps (3)(b)-(c) until all remote units of the plurality of remote units have been silenced; and

(4) enabling communication of the plurality of remote units in the fire loop.

2. The method of claim 1 , wherein each remote unit comprises a memory in which is stored a plurality of identifiers.

3. The method of claim 1 , wherein each remote unit is configured to randomly generate an identifier in response to a request.

4. The method of claim 1 , wherein the identifiers are comprised of binary digits.

5. The method of claim 1 , wherein the fire loop comprises one or more isolator units separating the fire loop into a plurality of loop portions, and wherein the method comprises:

opening all isolator units;

for each isolator unit, in sequence from one end of the fire loop:

closing the isolator unit; and

performing steps (1)-(3) in respect of the remote unit(s) not isolated from the fire panel; and

performing step (4) once all remote units of the plurality of remote units have been silenced.

6. The method of claim 1 , wherein one or more of the plurality of remote units comprise an embedded isolator, the one or more embedded isolator remote units separating the fire loop into a plurality of loop portions, and wherein the method comprises:

configuring the addresses of the embedded isolator remote units;

opening the embedded isolator of all embedded isolator remote units;

for each embedded isolator remote unit, in sequence from one end of the fire loop:

performing steps (1)-(3) in respect of the remote unit(s) not isolated from the fire panel; and

closing the embedded isolator of the embedded isolator remote unit; and

performing step (4) once all remote units of the plurality of remote units have been silenced.

7. The method of claim 1 , comprising:

(1) identifying that a new remote unit has been added to the fire loop;

(2) silencing the response of each of the configured remote units to identifier requests;

(3) requesting an initial identifier from the newly-added remote unit;

(4) assigning a unique address to the remote unit; and

(5) enabling communication of the plurality of remote units in the fire loop.

8. A fire system for a building, the fire system comprising:

a fire panel for monitoring the building and activating an alarm; and

a plurality of remote units electrically connected to the fire panel in a fire loop;

wherein the fire panel is configured with an addressing mode for addressing the plurality of remote units in the fire loop, the addressing mode comprising:

(1) requesting an initial identifier from each remote unit;

(2) for each remote unit which responds with a unique initial identifier:

(a) assigning a unique address to the remote unit; and

(b) silencing the response of the configured remote unit to further identifier requests;

(3) for each remote unit which responds with an initial identifier matching the initial identifier of at least one other remote unit:

(a) initialising an identifier array with the initial identifier for the remote unit in question;

(b) requesting a further identifier and adding it to the identifier array for the remote unit;

(c) for each remote unit which responds with a unique identifier array:

(i) assigning a unique address to the remote unit; and

(ii) silencing the response of the configured remote unit to further identifier requests;

(d) for each remote unit which responds with an identifier array matching the identifier array of at least one other remote unit, repeating steps (3)(b)-(c) until all remote units of the plurality of remote units have been silenced; and

(4) enabling communication of the plurality of remote units in the fire loop.

9. The fire system of claim 8 , wherein the fire panel is electrically connected to the fire loop at each end and is configured to be able to control the voltage and/or current in the fire loop from either end of the fire loop.

10. The fire system of claim 8 , wherein each remote unit comprises a memory in which is stored a plurality of identifiers.

11. The fire system of claim 8 , wherein each remote unit is configured to randomly generate an identifier in response to a request.

12. The fire system of claim 8 , wherein the identifiers are comprised of binary digits.

13. The fire system of claim 8 , wherein the fire loop comprises one or more isolator units separating the fire loop into a plurality of loop portions, and wherein the addressing mode comprises:

opening all isolator units;

for each isolator unit, in sequence from one end of the fire loop:

closing the isolator unit; and

performing steps (1)-(3) in respect of the remote unit(s) not isolated from the fire panel; and

performing step (4) once all remote units of the plurality of remote units have been silenced.

14. The fire system of claim 8 , wherein one or more of the plurality of remote units comprise an embedded isolator, the one or more embedded isolator remote units separating the fire loop into a plurality of loop portions, and wherein the addressing mode comprises:

configuring the addresses of the embedded isolator remote units;

opening the embedded isolator of all embedded isolator remote units;

for each embedded isolator remote unit, in sequence from one end of the fire loop:

performing steps (1)-(3) in respect of the remote unit(s) not isolated from the fire panel; and

closing the embedded isolator of the embedded isolator remote unit; and

performing step (4) once all remote units of the plurality of remote units have been silenced.

15. A computer-readable storage medium comprising instructions which, when executed by a processor of a fire panel, will cause the fire panel to perform a method of addressing a plurality of remote units electrically connected to the fire panel in a fire loop, and the method comprises:

(1) requesting an initial identifier from each remote unit;

(2) for each remote unit which responds with a unique initial identifier:

(a) assigning a unique address to the remote unit; and

(b) silencing the response of the configured remote unit to further identifier requests;

(3) for each remote unit which responds with an initial identifier matching the initial identifier of at least one other remote unit:

(a) initialising an identifier array with the initial identifier for the remote unit in question;

(b) requesting another identifier and adding it to the identifier array for the remote unit;

(c) for each remote unit which responds with a unique identifier array:

(i) assigning a unique address to the remote unit; and

(ii) silencing the response of the configured remote unit to further identifier requests;

(d) for each remote unit which responds with an identifier array matching the identifier array of at least one other remote unit, repeating steps (3)(b)-(c) until all remote units of the plurality of remote units have been silenced; and

(4) enabling communication of the plurality of remote units in the fire loop.