API RP 554-1:2007 pdf download
API RP 554-1:2007 pdf download.Process Control Systems Part 1—Process Control Systems Functions and Functional Specification Development.
Process Safety Management (PSM): A management process that results in process hazards being identified and suitable safeguards established, and which provides management of change procedures that ensure tha changes to processes are similarly addressed.
Programmable Logic Controller (PLC): Refers to a stand alone or separately networked microprocessor based control module that performs a variety of data acquisition and control functions. Most functions performed are discrete control functions, but Continuous functions may also be performed. A PLC typically will have its own dedicated 10 equipment and may also have dedicated shared display functions.
Redundant Arrays of Independent Disks (RAID): A distributed storage system spanning disk arrays and automated libraries of hard disks, optical disks, tapes or other bulk storage. RAID applications arc often applied to ensure that data is duplicated among disks so that failure of any one disk will not cause loss of function or of the data saved.
Reliability: Refers to the probability that a system or device will perform its function when required.
Router: A communications network device that learns the location of devices on a multi-segment communications network and reduces traffic on any one segment by repeating messages only for the devices connected to that segment.
Safety Instrumented System (SIS): Refurs to a system that is intended to protect against specific identified process hazards. Note: SIS are not within the scope of this Recommended Practice.
Safety Integrity Level (SIL): Refers to the availability required for a Safety Instrumented System (SIS). SIL is a measure of the probability that the SIS will operate when required to,
Safety Requirements Specification (SRS): Refers to a specitication associated with a Safety lnstrumcnted System that specifics basic functional, implementation, documentation and testing requirements that are to be met in order for the system to satisfy its intended Safety Integrity Level.
Sequencing Control: Refers to control functions that involve a series of steps, usually involving discrete controls, that arc executed in a pre-defined order and which may be repeated after all steps are completed. Normally sequencing control is a portion of a larger processing scheme and does not produce a final or intermediate product.
Virtual Private Network (VPN): The use of encryption to implement a secure connection through an otherwise insecure network, typically the Internet. VPNs are generally cheaper than real private networks using private lines but rely on having the same encryption system at both ends. The encryption may be performed by firewall software or possibly by routers.
Wide Area Network (WAN): A communications network that uses such devices as common dedicated communication systems to span a larger geographic area than can be covered by a LAN.
Workstation: Refurs to a computing resourve that is used for general business functions such as c-mail, word processing. internet access, etc.. but not used as a Process Control System HMI.
2 Process Control System Planning and Conceptual Design Basis
This section describes the process required to develop the overall requirements for a Process Control System prior to starting detailed design. Changes in control and information system technology have allowed the Process Control System to perform many more functions and intertitce with other business activities. In some eases, the Process Control System may perform some business functions that were not historically possible to do within previous technologies. Therefore, it is critical to define the boundaries of the Process Control System and the functions to be perfonned. The results of this process will have substantial impact upon initial implementation cost, schedule, lifecycle Cost, operability and maintainability of the Process Control System, especially if needed functions are not identified prior to design.
2.1 BUSINESS DRIVERS
The design of a Process Control System is ultimately determined by business needs and economic justifications of each of its functions. Many functions are required just from an operating necessity point of view—a Process Control System is required to operate a process. Some of the other business related functions performed by a Process Control Systems will be determined by other business needs.
