Controls Engineers are responsible for the design of an automation or control system. Their primary responsibility is the programming/configuration of the application code in a PLC, PAC or DCS (etc.) necessary to execute algorithms defining the operation of a piece of equipment. In support of this function, they are typically responsible for integrating automation devices into the controller engineering tools and parameterising those devices with all information necessary for their correct functional operation.
Within Controls Engineer, there are multiple disciplines, including safety engineer, PLC programmer and process automation engineer, all of whom fulfil essentially the same function but with differing expertise.