Abstract: Process control instruments having local intrinsic safety barriers and methods of manufacturing the same are disclosed. An example field instrument for a process control assembly includes a non-protection compartment, intrinsically safe circuitry positioned in the non-protection compartment, a protection compartment, non-intrinsically safe circuitry positioned in the protection compartment, and local barrier circuitry positioned in the protection compartment to operatively couple the non-intrinsically safe circuitry to the intrinsically safe circuitry, the local barrier circuitry to prevent the intrinsically safe circuitry from receiving an electrical energy that is greater than an electrical energy threshold from the non-intrinsically safe circuitry.

Abstract: Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to an I/P coil of the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level. The controller may remove the fixed voltage applied to the I/P coil when the maximum current level is reached or when a threshold period of time has elapsed from the application of the fixed voltage to the I/P coil. The controller may diagnose, based on whether the digital logic line trip occurred prior to removing the fixed voltage, a failure in the I/P converter.

Abstract: Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level, and an elapsed time from the application of the fixed voltage. The controller may compare the amount of time elapsed from the application of the fixed voltage to an expected amount of elapsed time from the application of the fixed voltage to the I/P coil after which a digital logic line trip will occur for a properly functioning I/P coil and diagnose, based on the comparison, a failure in the I/P converter.

Abstract: Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to an I/P coil of the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level. The controller may remove the fixed voltage applied to the I/P coil when the maximum current level is reached or when a threshold period of time has elapsed from the application of the fixed voltage to the I/P coil. The controller may diagnose, based on whether the digital logic line trip occurred prior to removing the fixed voltage, a failure in the I/P converter.

Abstract: Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level, and an elapsed time from the application of the fixed voltage. The controller may compare the amount of time elapsed from the application of the fixed voltage to an expected amount of elapsed time from the application of the fixed voltage to the I/P coil after which a digital logic line trip will occur for a properly functioning I/P coil and diagnose, based on the comparison, a failure in the I/P converter.