Intrinsically safe Zener diode barrier with indication

Patent metadata

Field	Value
Publication number	US-10845395-B2
Application number	US-201815891808-A
Country	US
Kind code	B2
Filing date	Feb 8, 2018
Priority date	Feb 8, 2018
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

A circuit device can be implemented, which includes a zener diode barrier composed of one or more zener diodes. The circuit device further includes one or more detection circuits electronically in series with the zener diode (or zener diodes) of the zener diode barrier. The zener diode barrier functions as an IS (Intrinsically Safe) barrier. The detection circuit (or circuits) facilitates the production of detailed information concerning different types of events detected by the detection circuit(s).

First claim

The invention claimed is:

1. A circuit device, comprising:
a zener diode barrier having at least one zener diode among dual redundant zener diodes;
at least one detection circuit that is connected electronically to a ground and which is electronically in series with said at least one zener diode of said zener diode barrier and provides a detection voltage, wherein said zener diode barrier comprises an IS (Intrinsically Safe) barrier having at least two redundant circuit paths, such that said at least one detection circuit facilitates a production of detailed information about events detected by said at least one detection circuit;
wherein said at least one detection circuit comprises a current transformer based detection circuit that includes a current transformer that detects short pulses when said at least one zener diode initially turns on; and
wherein said at least one detection circuit further comprises at least one of:
a first detection circuit that detects long duration faults,
a second detection circuit that detects surges over a length of time, and
a third detection circuit that detects fast transients,

wherein said first detection circuit, said second detection circuit and said third detection circuit are operable to detect different amounts of current, while providing information regarding said events including a severity of said long duration faults, said surges over said length of time, and said fast transients.

2. The device of claim 1 wherein said current transformer includes a transformer coil that is rated for a maximum fault current as specified by an IS safety standard and wherein said at least one zener diode among said dual redundant zener diodes regulates voltages to a maximum safe value as specified by said IS safety standard.

3. The device of claim 1 wherein said at least one zener diode is further connected electronically to an inductor fuse and a resistor.

4. The device of claim 1 further comprising a processor that processes at least one output from said at least one detection circuit.

5. The device of claim 4 wherein said processor comprises an embedded processor that uses a surface mount form factor.

6. The device of claim 4 wherein said processor comprises a microcontroller.

7. The device of claim 1 further comprising an external monitoring device that monitors at least one output from said at least one detection circuit.

8. A circuit device, comprising:
a zener diode barrier having at least one zener diode among dual redundant zener diodes, wherein said at least one zener diode is connected electronically to an inductor fuse and a resistor;
at least one detection circuit that is connected electronically to a ground and which is electronically in series with said at least one zener diode of said zener diode barrier and provides a detection voltage, wherein said zener diode barrier comprises an IS (Intrinsically Safe) barrier having at least two redundant paths, such that said at least one detection circuit facilitates a production of detailed information about events detected by said at least one detection circuit;
a processor that processes at least one output from said at least one detection circuit;
wherein said at least one detection circuit comprises a current transformer based detection circuit that includes a current transformer that detects short pulses when said at least one zener diode initially turns on; and
wherein said at least one detection circuit further comprises at least one of:
a first detection circuit that detects long duration faults,
a second detection circuit that detects surges over a length of time, and
a third detection circuit that detects fast transients,

wherein said first detection circuit, said second detection circuit and said third detection circuit are operable to detect different amounts of current, while providing information regarding said events including a severity of said long duration faults, said surges over said length of time, and said fast transients.

9. The device of claim 8 wherein said current transformer includes a transformer coil that is rated for a maximum fault current as specified by an IS safety standard and wherein said at least one zener diode among said dual redundant zener diodes regulates voltages to a maximum safe value as specified by said IS safety standard.

10. The device of claim 8 wherein said possible types of events include long durations faults, surges that last over a particular length of time, fast transients, or a different amount of current.

11. A method of operating a circuit device, said method comprising:
providing a zener diode barrier having at least one zener diode among dual redundant zener diodes; and
facilitating a production of detailed information about events detected by at least one detection circuit that is connected electronically to a ground and which is electronically in series with said at least one zener diode of said zener diode barrier having at least two redundant circuit paths, wherein said zener diode barrier comprises an IS (Intrinsically Safe) barrier;
wherein said at least one detection circuit comprises a current transformer based detection circuit that includes a current transformer that detects short pulses when said at least one zener diode initially turns on; and
wherein said at least one detection circuit further comprises at least one of:
a first detection circuit that detects long duration faults,
a second detection circuit that detects surges over a length of time, and
a third detection circuit that detects fast transients,

wherein said first detection circuit, said second detection circuit and said third detection circuit are operable to detect different amounts of current, while providing information regarding said events including a severity of said long duration faults, said surges over said length of time, and said fast transients.

12. The method of claim 11 further comprising:
detecting short pulses when said at least one zener diode initially turns on, wherein said at least one detection circuit comprises a current transformer based detection circuit comprising a current transformer that detects said short pulses; and
detecting a period while said at least one zener diode is conducting, wherein said detection circuit comprises an opto-coupler based detection circuit that includes an opto-coupler that detects said period, wherein said current transformer includes a transformer coil that is rated for a maximum fault current as specified by an IS safety standard and wherein said opto-coupler is rated for a maximum fault current as specified by said IS safety standard.

Assignees

• Honeywell Int Inc

Inventors

• Williams Michael

Classifications

• G01R31/2633

  for measuring switching properties thereof · CPC title

• G01R31/2827

  Testing of electronic protection circuits (testing switches G01R31/327; checking alarm systems G08B29/00; self test of summation current transformers H02H3/335) · CPC title

• H02H9/041

  using a short-circuiting device · CPC title

• H02H9/008

  Intrinsically safe circuits · CPC title

• H02H9/042

  comprising means to limit the absorbed power or indicate damaged over-voltage protection device · CPC title