Industrial process variable transmitter with isolated power scavenging intrinsically safe pulse output circuitry
First Claim
1. An industrial process variable transmitter, comprising:
- a process variable sensor configured to sense a process variable;
measurement circuitry coupled to the process variable sensor configured to provide a measured output as a function of the process variable;
output circuitry, comprising;
a loop connection configured to couple to a process control loop;
an optical sensor configured to receive the measured output from the measurement circuitry;
a second optical sensor configured to receive the measured output from the measurement circuitry;
a switching device configured to apply pulses to the process control loop in response to an output from the optical sensor;
power supply circuitry configured to power the optical sensor with power received from a power source through the process control loop and loop connection; and
wherein the optical sensor and the second optical sensor are configured to operate in a push/pull configuration.
2 Assignments
0 Petitions
Accused Products
Abstract
An industrial process variable transmitter includes a process variable sensor configured to sense a process variable. Measurement circuitry is coupled to the process variable sensor and provides a measured output as a function of the process variable. Output circuitry includes a loop connection configured to couple to a process control loop. An optical sensor receives the measured output from the measurement circuitry. A switching device applies pulses to the process control loop in response to an output from the optical sensor. Power supply circuitry powers the optical sensor, a comparator, and/or the switching device with power received from the process control loop and loop connection.
22 Citations
18 Claims
-
1. An industrial process variable transmitter, comprising:
-
a process variable sensor configured to sense a process variable; measurement circuitry coupled to the process variable sensor configured to provide a measured output as a function of the process variable; output circuitry, comprising; a loop connection configured to couple to a process control loop; an optical sensor configured to receive the measured output from the measurement circuitry; a second optical sensor configured to receive the measured output from the measurement circuitry; a switching device configured to apply pulses to the process control loop in response to an output from the optical sensor; power supply circuitry configured to power the optical sensor with power received from a power source through the process control loop and loop connection; and wherein the optical sensor and the second optical sensor are configured to operate in a push/pull configuration. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method of communicating a process variable in a process variable transmitter, comprising:
-
sensing a process variable with a process variable sensor; providing a measured output signal related to the sensed process variable; receiving the measured output signal with an optical sensor; receiving the measured output signal with a second optical sensor; applying a pulse to a process control loop based upon an output from the optical sensor; powering the optical sensor with power received from the process control loop; and wherein the optical sensor and the second optical sensor are configured to operate in a push/pull configuration. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18)
-
Specification