Claims
- 1. A two-wire sensor device, comprising:
- a) switching means having a coil and a set of switch contacts, said switch contacts set to their open state or their latched closed state in response to a detector output signal applied to said coil for connecting/disconnecting an AC power source to/from an electrical load, said switch contact connected between a phase conductor of said AC source and a first terminal of said electrical load, wherein a second terminal of said electrical load is connected to a neutral conductor of said AC source;
- b) energy storage means electrically coupled at a first end to said phase conductor of said AC source and at a second end to said first terminal of said electrical load;
- c) charge control means interposed between said first end of said energy storage means and said phase conductor of said AC source for limiting, filtering and controlling a voltage across said energy storage means; and
- d) sensor means electrically connected across said energy storage means for sensing a condition being monitored and generating a detector output signal based thereon, said detector output signal being applied to said coil to set the switch contacts in said open state or said latched closed state in accordance with said detector output signal.
- 2. A two wire sensor device as defined in claim 1, wherein said sensor means is an occupancy detector that produces a first detector output signal if no persons are in the sensor means monitoring area aid said first detector signal is applied to said coil to place said switch contacts in their open state to prevent AC power being applied to said electrical load.
- 3. A two wire sensor device as defined in claim 2, wherein said sensor means produces a second detector output signal if persons are in the sensor means monitoring area and said second detector signal is applied to said coil to place said switch contacts in their latched closed state to permit AC power being applied to said electrical load.
- 4. A two wire sensor device as defined in claim 1, wherein each of said energy storage means, said charge control means and said sensor means are high impedance devices.
- 5. A two wire sensor device as defined in claim 2, wherein said energy storage means provides an operating voltage to said sensor means which said switch contacts are placed in their open state.
- 6. A two wire sensor device, as defined in claim 2, wherein said energy storage means receives energy to be stored therein when said switch Contacts are placed in their latched closed state.
- 7. A two wire sensor device, as defined in claim 6, wherein said energy storage means receives energy to be stored therein when said switch contacts are placed in their latched closed state.
- 8. A two wire sensor device as defined in Claim 1, further comprising:
- a) a transformer having a primary winding and a secondary winding;
- b) said transformer primary winding connected between said phase conductor of said AC power source aid said switch contacts; and
- c) said transformer secondary winding connected between said charge control means and ground whereby said energy storage means can receive energy to be stored therein from both said AC power source and said secondary winding of said transformer.
- 9. A two wire sensor device, as defined in claim in 8, wherein said energy storage means receives energy to be stored therein when said switch contacts are placed in their latched closed state.
- 10. A two wire sensor device, as defined in claim 8, wherein said energy storage means provides an operating voltage to said sensor means when said switch contacts are placed in their open state.
- 11. A two wire sensor device, as defined in claim 9, wherein said energy storage means provides an operating voltage to said sensor means when said switch contacts are placed in the open state.
Parent Case Info
This is a continuation of application Ser. No. 08/498,039 filed on Jul. 3, 1995, now U.S. Pat. No. 5,632,171 issued Apr. 22, 1997.
US Referenced Citations (7)
Continuations (1)
|
Number |
Date |
Country |
Parent |
498039 |
Jul 1995 |
|