Flowserve Corporation has announced the availability of the Limitorque MXa electric actuator with up to a SIL 3 safety rating. After passing rigorous failure mode effects design analysis and total time in service tests, the SIL 3 capable rating was obtained from Exida Certification Services.
The SIL 3 capable rated MXa is designed to provide reliable actuation in critical environments without compromising customers’ Safety Instrumented Systems. The actuator carries the safety rating in a one out of two configuration, requiring two actuators and valves to be installed into a SIL 3 rated environment.
The MXa features LimiGard™ technology that automatically monitors the health of the each coded signal and ensures that no component failure can cause the actuator to move unexpectedly. A unique absolute encoder desgined with Built-in Selft-Test capability is also featured, which confirms the sound operation of the encoder, ensuring the actuator is operating safely. The design of the encoder compares redundant signals, which is key to achieving SIL 3 capable rating.
The MXa SIL 3 capable rating is a standard configuration which includes S1 and S2 contacts and the monitor relay to ensure that the user does not need to utilize external SIL rated contacts to bypass the actuator’s internal contacts that are not SIL rated.