power plant : works ( Remote Terminal Unit (RTU) - Fiber Optic Communication Links - CATHODIC PROTECTION)

 

POWER PLANT

WORKS (Remote Terminal Unit (RTU) - 

   Fiber Optic Communication Links -  CATHODIC PROTECTION. )

    General :

a]         The Contractor shall furnish a complete communication system so as to establish remote telemetry of data/signals from custody transfer metering station,

 scraper launcher station and sectionalizing/emergency isolation valve (EVs).

b]         Communication equipment, devices including RTUs,

 controller, signal converters, controllers, fiber optic cable, fiber driver, patch panel, terminal blocks, etc.

 including hardware/software additions, changes, reconfiguration control center shall be supplied by the Contractor.

    Remote Terminal Unit (RTU)

The RTU shall conform to the applicable company standards and material system specifications,

RTU design

 RTU design shall meet the following hardware and software requirements as well:

 -     RTU shall be capable of being configured and programmed locally, by means of a portable man-machine interface.

 -      Terminals shall be designed for ease of access and disconnection for field service and card replacement.

 -       All terminals, I/O boards, and components shall be resistant to corrosion and rust.

 -       All circuitry and logic boards shall be protected against power surges and spikes caused by short-circuiting wiring, lightning strikes, or other power transients.

 -       The RTU shall be capable of handling the signals including digital inputs, digital outputs. Analog inputs, analog outputs, and pulse inputs (if applicable) as per the requirement laid down in Saudi Aramco standards.

 -     The RTU shall be able to communicate via an RS 232/485- serial link provided for interfacing with the fiber optic communication link.

 -      The RTU software shall provide several levels of security, which controls access to the RTU database.

 The security levels are accessed through a password system, which allows an authorized person to assign log-on identifications, log-on codes, and access levels to personnel.

 -      The RTU shall be capable of rejecting noise or interference caused by electromagnetic radiation at various frequencies including radio frequency, very high frequency, ultrahigh frequency, and microwave

.

 -      The RTU shall be capable of rejecting electrical interference propagated through the power source.

 -       The RTU shall be immune to interference by electromagnetic noise caused by variable speed drives, high voltage electrical transformers, and switchgear.

 -      All equipment and modules within the RTU enclosure shall be spaced to allow ease of maintenance, module removal, and terminations of field wiring.

 All internal wiring shall be clearly labeled per the drawings. 

Wiring shall be neat and routed through plastic wiring channels.

 -    All enclosures shall be complete with a document holder inside the door for holding all RTU documentation and drawings.

 -      The RTU enclosures shall be indoor cabinets, constructed of steel, and corrosion-resistant. 

    Fiber Optic Communication Links

a]         Fiber Optic Link 

- A fiber optic communication link shall be provided between RTUs at pp metering skid, scraper launcher station, EVs/sectionalizing valves and company  standards and material system specifications.

- The communication link shall be a fully functional link comprising all required communication devices including fiber driver, patch panel, terminal blocks, and other accessories.

-   The fiber optic cable shall be designed supplied, installed, and tested,

 -  The fiber optic cable shall be single mode, steel armored.

 The fiber optic cable shall run parallel to the gas pipeline.

b]         Fiber Optic Link with PP DCS

A fiber optic link shall be provided between the custody metering control and monitoring system and PP DCS. All necessary interface equipment along with fiber optic cable shall be provided to connect the custody metering skid with the PP main control room.

 

    CATHODIC PROTECTION

  The Contractor shall provide a Cathodic Protection System,  for complete underground portion of the pipeline and shall include all systems and equipment to prevent electrolytic corrosion.

The impressed current method is required and sacrificial anodes shall be used only where the impressed current is impracticable.

  The cathodic protection shall be designed, constructed, and tested in accordance with company standards, recommendations, and codes,

 

The impressed current cathodic protection system shall be automatically maintained at a voltage figure, which shall depend on the design of the system in particular, and the design of anode utilized.

 However, in the event that alterations to the voltage may be desirable when reviewing actual protection performance, the equipment shall be capable of being readjusted to a new figure or manually overridden.

 The minimum design life of impressed current cathodic protection shall be 20 years.