Automation of Water Resource Recovery Facilities. Water Environment Federation

      Contractors and system integrators will often have questions for the design team during the construction phase. Such questions, or RFI, and their responses must be documented and filed with other design and project documents for future reference. Electronic documentation systems with appropriate security measures and access rights can make it easy to archive and retrieve this information.

3.1.4 Meetings with Contractors and Suppliers

      The design team will meet with contractors and system suppliers often to clarify design issues that are not easily addressed in other forums. During the early phase of the contract, design engineers should schedule monthly meetings with the system integrator. Later meetings should include electrical contractors; heating, ventilation, and air-conditioning (HVAC) contractors; and other subcontractors for coordination purposes.

3.1.5 Site Visits

      Although a construction management team (i.e., resident engineer, field inspectors, etc.) typically handles daily construction activities, the design team should visit the job site periodically to address and resolve implementation issues such as alternate installation procedures that could affect the design and overall project success.

3.1.6 Factory Acceptance Tests

      Contracts for I&C systems typically specify that systems must be fully tested at the manufacturer’s facility before shipment. Depending on the size and type of control system, factory tests may involve simulation software (Blevins et al., 2000; Dougall, 1997).

      The design engineer, end user personnel, or other designated parties typically witness this control system testing to ensure that the system is fully debugged, complies with design requirements, and is free of internal-wiring errors when the equipment leaves the factory. This reduces control system startup time and confines most of the remaining errors to field wiring or other field-related issues.

      At least 2 months before testing begins, the contractor must submit a schedule of test dates and a factory test procedure to the engineer and owner. The factory test procedure must include all testing steps, checklists, and settings and a list of all test equipment to be used to verify that the scheduled testing will fulfill contract requirements.

      When factory tests have been completed successfully, the contractor’s control system supplier should submit a report to the design engineer with the test results that clearly indicates that all deficiencies found during the factory test were corrected. Equipment should not be shipped until the contractor’s control system supplier receives a notice from the engineer that the test results were acceptable.

3.1.6.1 System Performance

      Before the witnessed factory test, the instrumentation system supplier should perform a full-system test, during which the entire system must operate continuously for at least 100 hours without failure, in accordance with the requirements of the specifications and drawings. The purpose of this test is to ensure that any component failures are discovered before the witnessed factory test begins.

      This test should verify that all the components work properly as an integrated system. It involves assembling the entire control system (i.e., hardware, software, peripheral devices, and interconnecting cables) on the factory test floor and using a workstation loaded with simulation software (simple control systems can typically be verified without simulation software) to operate the control system and simulate both treatment processes and signals from field devices that cannot be connected to the panel. If any component fails during this test, it should be replaced and the test restarted.

      While the entire system is assembled, the supplier should inspect all panels, consoles, and cabinets to ensure that the following items and functions are correct and consistent:

      • Nameplates and tags;

      • Wire sizes and color coding;

      • Terminal block contract ratings and number;

      • Annunciator and terminal block spares;

      • Proper wiring practices and grounding; and

      • Enclosure flatness, finish, and color.

      Once the 100-hour test has been successfully completed, the contractor should certify this success in writing, submit the document to the design engineer, and schedule witness testing.

3.1.6.2 Hardware Testing

      Each hardware component should be tested to verify that it operates properly by itself. Such tests should include

      • Alternating current and direct current power checks,

      • Power-failure and -restart tests,

      • Diagnostics checks, and

      • Proof of all specified functions.

      In addition, all I/O devices and their components should be tested to verify operability and basic calibration. Where applicable, proper communication among system components should be verified. Communication between each remote I/O and control panel PLC and the master control panel PLC should also be demonstrated.

3.1.6.3 Software Testing

      The contractor should demonstrate that all system software, especially its security components, works as intended. For small or simple systems, this test may involve wiring some simulated signals (toggle switches, lights, analog signal from a signal generator, etc.) to the control panel. For larger or more complex systems, this test should involve the use of simulation software installed on a separate computer. During this test, the contractor should demonstrate operation and display of all software based on a simulation involving 100% of physical I/Os, including analog, discrete, and virtual I/Os.

3.1.6.4 Simulation Software

      Many system integrators now use simulation software to test program logic before scheduling a factory test. The contract should specify that simulation software be used during testing as well. This software should have the following features:

      • Process-specific libraries of unit operations and physical properties;

      • The ability to define characteristics (e.g., flow, level, temperature, and pressure) of discrete devices, loops, and objects in the control system model;

      • The ability to simulate all process control system signals, alarms, and shutdown scenarios in real time;

      • The ability to model all process feedback using graphics and symbols;

      • Full, workstation-based control over the behavior of each object in the model;

      • The ability to develop custom graphics;

      • “Point-and-click” access to object parameters as they are being executed in the background;

      • The ability to communicate directly with operator interface terminal (OIT) software;

      • The ability to communicate with specified PLCs;

      • Operator-training tools that meet Occupational Safety and Health Administration 1910.119 recommendations; and

      • Tag numbers for panels, equipment, and instruments used in simulation software should be identical to those in the contract P&IDs.

      In addition, the contractor should be required to retain the services of the simulation software supplier’s factory-trained technician. These services should be provided during factory testing, startup, field testing, and training. The contractor should bear all costs (including transportation and lodging expenses) related to these services. A comprehensive guide to factory testing is presented in ISA’s (2011) Automated Systems in the Process Industry—Factory Acceptance Test (FAT),