Systems and/or Devices for Providing an Isolated Analog Output or Analog Input

• US 20090079612A1
• Filed: 09/05/2008
• Published: 03/26/2009
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: Parfitt, Steven Perry
• Granted Patent: US 7,786,919 B2
• Time in Patent Office: Days
• US Class Current: 341/157
• CPC Class Codes: G05B 19/054 Input/output
• CPC Class Codes: G05B 2219/1182 I-O isolation, optical
• CPC Class Codes: G05B 2219/25461 Transformer separation

Abstract

Certain exemplary embodiments can provide a method, which can comprise transmitting a recovered analog input signal to a programmable logic controller. The recovered analog input signal can be converted, on a downstream side of an isolation device, from a converted signal. The recovered analog input signal can have a voltage value that varies according to a frequency value of the converted signal.

Claims

1. A system comprising:

a voltage-to-frequency converter adapted to;

receive an analog input signal that represents a sensor-detected physical property;

convert said analog input signal to a converted signal having a constant voltage and a frequency value that varies according to a voltage value of said analog input signal; and

transmit said converted signal across an isolation device; and

a frequency-to-voltage converter adapted to;

receive said converted signal;

convert said converted signal to a recovered analog input signal having a voltage value that varies according to said frequency value of said converted signal; and

transmit said recovered analog input signal to a programmable logic controller.

2. The system of claim 1, wherein:

a programmable logic controller adapted to process said recovered analog input signal to obtain an input value for said sensor-detected physical property.

3. The system of claim 1, wherein:

an analog input module adapted to convert said recovered analog input signal to a digital input signal.

4. The system of claim 1, wherein

a programmable logic controller adapted to process a digital signal, said digital signal encoding an input value obtained from said recovered analog input signal, said input value corresponding to said sensor-detected physical property.

5. The system of claim 1, wherein:

a human machine interface adapted to render an input value corresponding to said sensor-detected physical property.

6. The system of claim 1, wherein:

said isolation device is an opto-isolator.

7. The system of claim 1, wherein:

said isolation device is a transformer.

8. A system comprising:

a voltage-to-frequency converter adapted to;

receive an analog output signal adapted to control an actuator;

convert said analog output signal to a converted signal having a constant voltage and a frequency value that varies according to a voltage value of said analog output signal;

transmit said converted signal across an isolation device; and

a frequency-to-voltage converter adapted to;

receive said converted signal;

convert said converted signal to a recovered analog output signal having a voltage value that varies according to said frequency value of said converted signal; and

transmit said analog output signal to said actuator.

9. The system of claim 8, further comprising:

a programmable logic controller adapted to create said analog output signal.

10. The system of claim 8, further comprising:

an output module adapted to create said analog output signal.

11. The system of claim 8, further comprising:

a programmable logic controller adapted to provide an analog output value corresponding to said analog output signal to a human machine interface.

12. The system of claim 8, further comprising:

a human machine interface adapted to render an analog output value corresponding to said analog output signal.

13. The system of claim 8, further comprising:

said isolation device is an opto-isolator.

14. The system of claim 8, further comprising:

said isolation device is a transformer.

15. A method comprising:

receiving an analog input signal that represents a sensor-detected physical property;

converting said analog input signal to a converted signal having a constant voltage and a frequency value that varies according to a voltage value of said analog input signal;

transmitting said converted signal across an isolation device;

on a downstream side of said isolation device, converting said converted signal to a recovered analog input signal having a voltage value that varies according to said frequency value of said converted signal; and

transmitting said recovered analog input signal to a programmable logic controller.

16. A method comprising:

transmitting a recovered analog input signal to a programmable logic controller, a converted signal, on a downstream side of an isolation device, converted to said recovered analog input signal, said recovered analog input signal having a voltage value that varies according to a frequency value of said converted signal, said converted signal transmitted across said isolation device, an analog input signal converted to said converted signal having a constant voltage and a frequency value that varies according to a voltage value of said analog input signal, said analog input signal representative of a sensor-detected physical property.