Emerson has recently released its ASCO 141 Series Advanced Redundant Control System (ARCS) to provide a redundant solution for emergency shutdown valve applications, such as those found in the chemical, power, oil and gas industries.
It includes various redundant solenoid configurations to enhance process reliability and meet specific safety or reliability requirements. Its single inlet/single outlet design offers a streamlined installation process compared to traditional bypass systems, while almost eliminating potential failure points. The ASCO 141 series ARCS is designed for use as a component in safety instrumented systems. Using 1oo2, 2oo2 or 2oo3 voting solenoids to enhance the reliability of the circuit, it functions as a redundant pneumatics tripping device to control the pilot air signal to a process valve actuator.
The ARCS features either two or four electrically actuated solenoid valves, visual indicators and a manually controlled bypass or isolation valve. The control functionality allows for maintenance of the solenoid valves without having to shut down the process valve as the use of the maintenance bypass or isolation valve is not required for functional testing of the ARCS.