ASI network for explosion-hazard areas

• US 20080224850A1
• Filed: 02/22/2008
• Published: 09/18/2008
• Est. Priority Date: 02/27/2007
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Wiesgickl, Bernhard, Korff, Maximilian, Schiff, Andreas, Indefrey, Klaus
• Granted Patent: US 8,242,901 B2
• Time in Patent Office: Days
• US Class Current: 340/532
• CPC Class Codes: H02H 9/008 Intrinsically safe circuits

Abstract

At least one embodiment of the invention relates to a fieldbus system, in particular for use in an explosion-hazard area. The fieldbus system, in at least one embodiment, has a plurality of bus line sections with bus lines; an isolating element, by which in each case two of the plurality of bus line sections are coupled to one another and which galvanically isolates the bus lines of the two bus line sections from one another such that this prevents any direct current flowing between the bus lines of the two bus line sections and communication signals are transmitted between the two bus line sections; and a supply source for each of the bus line sections, in order to provide an electrical power supply for field devices which can be connected to the respective bus line section.

Claims

1. A fieldbus system, comprising:

a plurality of bus line sections with bus lines;

isolating elements, each coupling two of the plurality of bus line sections to one another, to galvanically isolate the bus lines of the two bus line sections from one another such that any direct current is prevented from flowing between the bus lines of the two bus line sections and such that transmission of communication signals is permitted between the two bus line sections; and

a supply source for each of the bus line sections, to provide an electrical power supply for field devices connectable to a respective bus line section, a plurality of the bus line sections being connected, via isolating elements, to form a series circuit.

2. The fieldbus system as claimed in claim 1, wherein terminating impedances are provided at the ends of the bus lines.

3. The fieldbus system as claimed in claim 1, wherein the isolating elements are each connected to two bus lines of the two bus line sections, wherein the isolating elements include a transformer with transformer coils and wherein each of the transformer coils is connected in series with a respective isolating capacitance between the two bus lines of the corresponding bus line section.

4. The fieldbus system as claimed in claim 3, wherein a suppressor diode is connected directly in parallel with at least one of the transformer coils of the transformer.

5. The fieldbus system as claimed in claim 1, wherein the supply sources for the bus line sections are designed to be current and voltage limited.

6. The fieldbus system as claimed in claim 1, wherein one or more of the supply sources is coupled via a decoupling inductance to bus lines of a corresponding bus line section.

7. The fieldbus system as claimed in claim 1, wherein the bus line sections are at least partially arranged in an explosion-hazard area, and wherein the supply sources for the bus line sections are arranged outside the explosion-hazard area.

8. The fieldbus system as claimed in claim 1, wherein at least one of the bus line sections is connected via a connection section to a controller for providing communication with field devices connected to the bus line sections.

9. The fieldbus system as claimed in claim 8, wherein a plurality of bus line sections are coupled via a respective isolating element to the connection section.

10. The fieldbus system as claimed in claim 1, wherein the fieldbus system is for use in an explosion-hazard area.

11. The fieldbus system as claimed in claim 2, wherein the isolating elements are each connected to two bus lines of the two bus line sections, wherein the isolating elements include a transformer with transformer coils and wherein each of the transformer coils is connected in series with a respective isolating capacitance between the two bus lines of the corresponding bus line section.

12. The fieldbus system as claimed in claim 11, wherein a suppressor diode is connected directly in parallel with at least one of the transformer coils of the transformer.

13. The fieldbus system as claimed in claim 2, wherein the supply sources for the bus line sections are designed to be current and voltage limited.

14. The fieldbus system as claimed in claim 2, wherein one or more of the supply sources is coupled via a decoupling inductance to bus lines of a corresponding bus line section.

15. The fieldbus system as claimed in claim 2, wherein the bus line sections are at least partially arranged in an explosion-hazard area, and wherein the supply sources for the bus line sections are arranged outside the explosion-hazard area.

16. The fieldbus system as claimed in claim 2, wherein at least one of the bus line sections is connected via a connection section to a controller for providing communication with field devices connected to the bus line sections.

17. The fieldbus system as claimed in claim 16, wherein a plurality of bus line sections are coupled via a respective isolating element to the connection section.