Methods and apparatus for controlling and testing a notification applicance circuit

• US 20100073175A1
• Filed: 02/06/2009
• Published: 03/25/2010
• Est. Priority Date: 02/08/2008
• Status: Active Grant

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Industry Incorporated (Siemens AG)
• Inventors: Lontka, Karen D.
• Granted Patent: US 8,446,285 B2
• Time in Patent Office: Days
• US Class Current: 340/635
• CPC Class Codes: G08B 29/123 of line circuits

Abstract

An arrangement for use in a safety notification system includes a source of negative voltage, a first resistor arrangement, and a circuit arrangement. The first resistor arrangement is coupled between the source of negative voltage and the signal output of the safety notification system. The circuit arrangement is configured to detect a first voltage at the signal output of the safety notification system, and to generate a trouble signal output if the first voltage at the signal output is above a first threshold or below a second threshold.

Claims

1. An arrangement for use in a safety notification system, comprising:

a) a source of negative voltage;

b) a first resistor arrangement coupled between the source of negative voltage and the signal output of the safety notification system;

c) a circuit arrangement configured to detect a first voltage at the signal output of the safety notification system, the circuit arrangement configured to generate a trouble signal output if the first voltage at the signal output is above a first threshold or below a second threshold.

2. The arrangement of claim 1, wherein the circuit arrangement includes a measurement circuit configured to generate a measurement signal output based on the first voltage, and a processing circuit configured to obtain the measurement signal output and to generate a comparison value representative of a difference between a reference voltage and the first voltage.

3. The arrangement of claim 2, wherein the reference voltage is equal to the negative voltage divided over the first resistor arrangement and an end of line resistor arrangement of the notification appliance circuit.

4. The arrangement of claim 2, wherein the processing circuit is configured to generate the trouble signal if the comparison signal indicates that the first voltage is above the first threshold or below the second threshold.

5. The arrangement of claim 4, wherein the processing circuit performs control operations for other devices.

6. The arrangement of claim 1, further comprising:

first, second, third and four outputs configurable for first and second wiring configurations of notification appliance circuits;

a configurable terminal arrangement having first and second configurations corresponding to the first and second wiring configurations; and

an end-of-line resistor; and

wherein the configurable terminal arrangement in the first configuration couples the end-of-line resistor between the second and third outputs, and wherein the jumper in the second configuration decouples the end-of-line resistor from the second and third outputs.

7. The arrangement of claim 6, wherein the jumper in the first configuration further couples the third output to ground via a forward biased diode.

8. The arrangement of claim 6, wherein the end-of-line resistor is coupled on a first side to ground via a forward biased diode.

9. An arrangement for use in a safety notification system, comprising:

a) a source of negative voltage;

b) a semiconductor switching device coupled between a source of positive voltage and a first signal output of the safety notification system;

c) a first resistor arrangement coupled between the source of negative voltage and the first signal output;

c) a circuit arrangement configured to detect a first voltage at the signal output of the safety notification system, the circuit arrangement configured to generate a trouble signal output if the first voltage at the signal output is above a first threshold or below a second threshold.

10. The arrangement of claim 9, wherein the semiconductor switching device comprises a MOSFET.

11. The arrangement of claim 9, wherein the circuit arrangement includes a measurement circuit configured to generate a measurement signal output based on the first voltage, and a processing circuit configured to obtain the measurement signal output and to generate a comparison value representative of a difference between a reference voltage and the first voltage.

12. The arrangement of claim 11, wherein the reference voltage is equal to the negative voltage divided over the first resistor arrangement and an end of line resistor arrangement of the notification appliance circuit.

13. The arrangement of claim 11, wherein the processing circuit is configured to generate the trouble signal if the comparison signal indicates that the first voltage is above the first threshold or below the second threshold.

14. The arrangement of claim 13, wherein the processing circuit performs control operations for other devices.

15. The arrangement of claim 9, further comprising:

first, second, third and four outputs configurable for first and second wiring configurations of notification appliance circuits;

a configurable terminal arrangement having first and second configurations corresponding to the first and second wiring configurations; and

an end-of-line resistor; and

wherein the configurable terminal arrangement in the first configuration couples the end-of-line resistor between the second and third outputs, and wherein the jumper in the second configuration decouples the end-of-line resistor from the second and third outputs.

16. The arrangement of claim 15, wherein the jumper in the first configuration further couples the third output to ground via a forward biased diode.

17. The arrangement of claim 15, wherein the end-of-line resistor is coupled on a first side to ground via a forward biased diode.

18. The arrangement of claim 15, further comprising:

a second signal output of the safety notification system;

a second semiconductor switching device coupled between the source of positive voltage and the second signal output;

and wherein in the first configuration, the configurable terminal arrangement couples second signal output to the second output, and in the first arrangement, the configurable terminal decouples the second signal output from the second output.