Procedure for Instrument Junction Box Installation


All permanent materials, consumables and junction box for installation shall be prepared and checked prior to installation.

Ensure that working areas are ready for installation to include availability of scaffolding (if needed), supports and access to avoid delays of the activities.

Study and prepare all instrument installation requirements and related references such as IFC, layout and Technical Scope of Work, work permit requirements, and work procedures.


  1. Survey the location of junction box to be installed comparing the installation details and layout. Ensuring free access for maintenance and no obstruction. Should there be discrepancies or obstructions be found in the construction drawings, site queries should be raised to contractor for further site instruction.
  2. Prior to installation, the junction box shall be visually inspected for possible factory or handling damage. Where physical damage or non-compliance with the specification has been found, it shall be recorded using QC Material Receiving Inspection Report and reported immediately to contractor for disposition.

3. Before installing in position, junction box sections shall be opened up and inspected for cleanliness and to ensure no foreign bodies are present.
4. Junction boxes shall be identified by means of an engraved laminated plastic label. Generally black text with white background color. Junction boxes in shutdown service the text shall be white with red background color.

5. Check Instrument Junction Box Installation locations and provide markings to which elevations, mounting height and orientations should conform in the latest IFC drawings.

6. Install necessary fabricated supports and brackets for junction box as per EPC latest issued approved drawings. Welding shall be done for supports wherever necessary. 7. Install necessary miscellaneous foundation if required. 8. The support and/or bracket shall be inspected and checked against the fabrication shop drawing and instrument junction box mounting details. 9. Particular attention shall be paid to the fixing points for correct sizing and clearance.

10. All rough edges of the support or brackets shall have been removed; the assembly primed and painted in accordance with the Project Specification.
11. The installed support shall be inspected to ensure it is level, vertical and the whole assembly is rigid.
12. Provide 12AWG bonding wire (Green and Yellow) inside JB between door and body, and between back-pan panel and body.

13. The required minimum working clearance shall be maintained in front of all junction box and doors shall be free to be opened at a minimum of 90°. All field junction boxes shall be mounted vertically i.e.; the door shall be open form right-to-left. 14. Branch cables shall be approximately 70 meters long at average, from instrument to FF spur junction box, and 70 meters long at average from FF spur junction box to intermediate junction box.

15. Cable entries for the junction boxes shall be sequentially arrange and identified to avoid confusions and minimize unnecessary movements within the set point.

16. All cable entries to field junction boxes shall be through the bottom. A drain seal shall be installed on the conduit within 18 inches of the enclosure. All unused entry ports shall be fitted with approved plugs. 17. Conduit entries shall be through gasket hubs (Myers hub) provided by vendor. Gasket material shall be oil resistant. Conduit connection shall be NPT thread.

18. Power supply shall be checked as per connection wiring schedule.
19. All junction boxes shall be grounded to the main grid.
20. Where install miscellaneous foundation, finishing mortar for concrete
foundation with sunlight resistant coating as per project specification.
21 . Protection cover against damage during construction shall be provided.


Tools and equipment needed should be in good condition and must be checked by Instrument Supervisor prior to use in the construction area. These includes but not limited to:

  1. Set of Instrument Hand Tools and Fittings
  2. Bending and Cutting Machine
  3. Welding machine
  4. Chain Block/ Chain Puller
  5. Hydraulic Pallet Jack
  6. Common Hand Tools
  7. Electric Power Tools (i.e. electric drill, etc.)
  8. Knock Out Puncher with Hydraulic Foot Pump
  9. Set of Termination Tools
  10. Portable 120VAC, 60 Hz Gasoline Powered Generator


  1. Obtain necessary work permits from the concerned Department Representative intended for the area before starting any work.
  2. Conduct proper preparation to include required safety equipment and tools for the commencement of the work.
  3. Activities shall be executed in accordance with this procedure and related Saudi Aramco Standards and project specifications.
  4. Provide warning sign and sufficient barricade on working area. Only assigned personnel will be allowed in the area to maintain a safe work atmosphere.
  5. Conduct safety briefing to all working crew and remind all basic safety requirements to ensure a safe and healthy work flow.
  6. Continuous monitoring and inspection shall be implemented by the site supervisor/foreman together with the assigned safety engineer in the area.
  7. Any unsafe practices while performing the work activities shall be corrected immediately to avoid stoppage of the work.
  8. Good housekeeping shall be maintained in the duration of works. The site at all work activities shall be kept clean and tidy.
  9. Safety Engineer shall monitor the work activities to help and protect all assigned workers against exposure to safety hazards. He shall ensure that Personal Protective Equipment’s (PPE’s) are supplied and worn at all times.


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1 Response

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