Alarms for monitoring operation of sensors in a fire-suppression system

• US 6,195,002 B1
• Filed: 01/22/1999
• Issued: 02/27/2001
• Est. Priority Date: 01/22/1999
• Status: Expired due to Term

• Current Assignee: Richard P. Evans Jr
• Original Assignee: Richard P. Evans Jr
• Inventors: Wheeler, Steven R., Evans, Richard P. Jr.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US09/245,094
• Time in Patent Office: 767 Days
• Field of Search: 340/506, 340/691, 340/693.5, 340/693.9, 340/603, 340/606, 340/618, 340/525, 340/588, 340/589, 340/514, 169/56, 169/5, 169/23, 169/60, 137/551, 137/557, 137/561.R, 137/556.6, 137/312, 137/78.3, 137/624.11, 116/227, 116/112, 73/495, 700/282, 700/283, 700/284, 251/129.01
• US Class Current: 340/506
• CPC Class Codes: G08B 21/187 Machine fault alarms
• CPC Class Codes: Y10T 137/8158 With indicator, register, recorder, alarm or inspection means
• CPC Class Codes: Y10T 137/8326 Fluid pressure responsive indicator, recorder or alarm

Abstract

Alarms for testing sensors, particularly those used in fire-suppression systems, are described. In one aspect of the invention, the alarm includes an audio and/or a visual indicator operably coupled to the housing of a sensor. The audio indicator may be a speaker that beeps when the sensor is activated. The visual indicator may be one or more LEDs that are illuminated when the sensor is activated. The alarm also can be used to determine whether power and ground conductors extending to the sensor are properly connected. Additionally the alarm can be used to determine whether one or more conductors extending from the sensor to the control panel are properly connected. Certain applications of the invention are intended primarily for use with existing fire-suppression-systems. The invention also can be employed in new fire-suppression system installations using a dry-contact circuit embodiment of the invention (FIG. 5). The dry-contact circuit allows the present invention to be used with conventional pressure and flow sensors, and conventional alarm-monitoring circuitry.

Claims

1. An alarm for a fire-suppression system that includes a fluid-carrying conduit and at least one sensor mounted to the fluid-carrying conduit, the sensor having a first state indicating normal operation of the fire-suppression system and a second state indicating (1) a change in fluid flow or fluid pressure within the conduit or (2) movement of a valve controlling fluid flow to or through the conduit, the alarm comprising:

a first indicator mounted to the sensor, the first indicator being activated when the sensor is in the first state; and

a second indicator mounted to the sensor, the second indicator being activated when the sensor is in the second state; and

a sensor-signal output mechanism for informing a remote monitoring circuit when the sensor is in the second state, the sensor-signal output mechanism comprising a set of dry contacts that are open when the sensor is in the first state and are caused to close when the sensor is in the second state.

2. The alarm of claim 1, wherein the sensor provides a common, a normally-open, and a normally-closed output, the normally closed output energizing the first indicator when the sensor is in the first state, the normally-open output being closed and energizing the second indicator when the sensor is in the second state.

3. The alarm of claim 1 further comprising a control panel that is electrically coupled to the alarm by a conductor, the control panel remotely monitoring whether the sensor is in the first or second state.

4. A fire-suppression system, comprising:

a fluid-carrying conduit for supplying fire extinguishing fluid to a sprinkler system;

a sensor coupled to the fluid-carrying conduit, the sensor comprising a sensor element positioned within the fluid-carrying conduit for detecting changes in fluid rate or fluid pressure within the conduit, the sensor providing a first output that is activated when the sensor is in a first state indicating normal operation, the sensor providing a second output that is activated when the sensor is in a second state, the second state indicating sensor detection of changes in fluid flow rate or fluid pressure;

a first light-emitting diode mounted to and extending through the housing of the sensor and electrically coupled to the first output, the fist light-emitting diode being electrically activated when the sensor is in the first state and being electrically deactivated when the sensor is in the second state;

a second light-emitting diode mounted to and extending through the housing of the sensor and electrically coupled to the second output, the second light-emitting diode being electrically activated when the sensor is in the second state and being electrically deactivated when the sensor is in the first state;

a set of dry contacts electrically coupled to the second output, the contacts being open when the sensor is in the first state and caused to close when the sensor is in the second state; and

a control panel electrically coupled to the contacts, the control panel activating an alarm condition when the sensor is in the second state.

5. The fire-suppression system of claim 4 further comprising a plurality of sensors mounted in the conduit.

6. The fire-suppression system of claim 5, wherein each of the sensors has a second-state output indicating the sensor has detected a change in fluid flow rate or fluid pressure, the second-state outputs being electrically coupled to the control panel.