Power distribution to nodes in a distributed system

• US 6,348,874 B1
• Filed: 10/14/1998
• Issued: 02/19/2002
• Est. Priority Date: 10/14/1998
• Status: Expired due to Term

• Current Assignee: Keysight Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Ii, Mutsuya, Cole, Wesley D., Eidson, John C., Sitte, Hans J.
• Primary Examiner(s): Zimmerman, Brian
• Assistant Examiner(s): Dalencourt, Yves
• Application Number:
  US09/172,525
• Time in Patent Office: 1,224 Days
• Field of Search: 340/825.01, 370/445, 370/446, 370/404, 370/524, 370/238
• US Class Current: 340/538
• CPC Class Codes: H04L 25/02 Details ; arrangements for supplying electrical power along data transmission lines systems for transmitting signals via power distribution lines H04B3/54

Abstract

A system in which remote nodes are supplied with electrical power using existing network communication links. A communication device in a system according to the present techniques routes electrical power to a remote node via a set of unused lines of a network communication link used for communication with the remote node. The electrical power distributed to the remote node may be AC or DC power.

Claims

1. A distributed system, comprising:

network communication link that conforms to an industry standard that specifies a set of data transmission lines and a set of unused lines;

communication device coupled to the network communication link, the communication device having circuitry for providing electrical power on the unused lines of the network communication link;

remote node coupled to the network communication link, the remote node having circuitry for obtaining electrical power from the unused lines of the network communication link;

circuitry for avoiding ground loops between the communication device and the remote node via an earth ground by maintaining a high degree of electrical isolation between a ground for circuitry in the communication device and the remote node and the earth ground.

2. The distributed system of claim 1, wherein the industry standard specifies a set of lines for full-duplex transmission and the communication device provides electrical power to the remote node via a subset of the lines allocated for full-duplex transmission.

3. The distributed system of claim 1, wherein the industry standard is a 10Base -T standard.

4. The distributed system of claim 1, further comprising circuitry for preventing a short circuit in the network communication link from affecting a voltage potential distributed on the unused lines.

5. The distributed system of claim 1, further comprising means for sensing a short circuit in the communication device and for transferring a message via a communication link that carries an indication of the short circuit.

6. The distributed system of claim 1, wherein the network communication link is contained in a cable with distinctive markings that indicate a powered network communication link.

7. The distributed system of claim 1, wherein the network communication link includes a pair of connectors which are keyed to a receptacle on the communication device and a receptacle on the remote node.

8. A communication device for a distributed system, comprising:

circuitry for providing electrical power on a set of unused lines of the network communication link of the distributed system wherein the network communication link conforms to an industry standard that specifies a set of data transmission lines and the unused lines;

circuitry for avoiding ground loops on the unused lines via an earth ground by maintaining a high degree of electrical isolation between a ground for circuitry in the communication device and the earth ground.

9. The communication device of claim 8, wherein the industry standard specifies a set of lines for full-duplex transmission and the communication device provides electrical power via a subset of the lines allocated for full-duplex transmission.

10. The communication device of claim 9, wherein the industry standard is a 10Base-T standard.

11. The communication device of claim 9, wherein the communication device is a repeater.

12. The communication device of claim 9, wherein the communication device is a router.

13. The communication device of claim 9, wherein the communication device is a switching hub.

14. The communication device of claim 9, wherein the communication device is a PC network card.

15. The communication device of claim 9, further comprising circuitry for preventing a short circuit in the network communication link from affecting a voltage potential distributed on the unused lines.

16. The communication device of claim 9, further comprising means for sensing a short circuit in the communication device and for transferring a message via a communication link that carries an indication of the short circuit.

17. The communication device of claim 9, further comprising a receptacle which is keyed to a connector of the network communication link.

18. A remote node for a distributed system, comprising:

circuitry for obtaining electrical power from a set of unused lines of the network communication link wherein the network communication link conforms to an industry standard that specifies a set of data transmission lines and the unused lines;

circuitry for avoiding ground loops on the unused lines via an earth ground by maintaining a high degree of electrical isolation between a ground for circuitry in the remote node and the earth ground.

19. The remote nod e of claim 18, wherein the industry standard specifies a set of lines for full-duplex transmission and the remote node obtains electrical power via a subset of the lines allocated for full-duplex transmission.

20. The remote node of claim 19, wherein the industry standard is a 10Base-T standard.

21. The remote node of claim 19, wherein the remote node is a sensor node.

22. The remote node of claim 19, wherein the remote node is an actuator node.

23. The remote node of claim 19, wherein the remote node is an application controller node.

24. The remote node of claim 19, wherein the remote node is a computer system.

25. The remote node of claim 19, further comprising an isolating power supply with transformer for preventing ground loops.

26. The remote node of claim 19, further comprising a receptacle which is keyed to a connector of the network communication link.