Instrument Loop Folders – Loop Check Preparation

Main keywords for this article are Instrument Loop Folders, Non Foundation Fieldbus Loop Folder Contents, Foundation Fieldbus Loop Folder Contents, Motor Operation Loop,Loop Check Preparation.

Instrument Loop Folders

The following documents are the requirements prior to the conduct of function or loop test known to be as Loop Folder. The following order of the loop folder index or contents will be;

Non Foundation Fieldbus Loop Folder Contents / Attachments

1. P&ID
2. Instrument Schedule
3. Installation Checklist & Location
4. Instrument Connection/Wiring
5. Instrument Air Piping Line Leak Test
6 . Instrument data Sheets
7 . Calibration Reports/ Certificates
8. Valve Seat & Leak Test Reports
9. Instrument Loop Diagram
10. PCSD Documentation
11 . Loop & Function Check/Test Report
12. Safe Work Checklist
13. Punch List

Foundation Fieldbus Loop Folder Contents / Attachments

1. P&ID
2. Instrument Schedule
3. Installation Checklist & Location
4. Instrument Connection/Wiring
5. Instrument Air Piping Line Leak Test
6. Instrument data Sheets
7. Calibration Reports/ Certificates
8. Valve Seat & Leak Test Reports
9. Instrument Loop Diagram
10. PCSD Documentation
11. Loop & Function Check/Test Report
12. Foundation Fieldbus Segment Verification report
13. Foundation Fieldbus Scan Time Calculation Sheet
12. Safe Work Checklist
13. Punch List

Motor Operation Loop

Person In-charge of Loop and Function test will contact the LV team when they are ready to rotate a motor.
I/O points should be confirmed with the motor operation 
Loop team will observe and verify the associated tags such as the following:

DO : to start the motor/ready to run
DI : Motor Start/Stop Al motor is running/run status
AI : motor ampere drawn
AI  : motor rotational speed
AI  : motor vibration
AI  : motor winding temperature

INSTRUMENTATION LOOP CHECK PREPARATION & INSTRUMENTATION LOOP CHECK WORK PROCEDURE

The applicable checks as indicated on the Loop Test diagram or the relevant loop drawings will be carried out. Each Loop in the Loop List serves as a check sheet and all items listed will be considered. Although instrumentation function and loop check is a two (2) person operation, individual tests can be carried out by individuals, but the  responsibility for the Loop as a unit shall rest with one (1) person who will fill in and sign the Loop or Function Tests Certificate after the completion of all applicable test. All individual checks incorporated in a Loop/Function Test will be carried out in a typical and logical sequence as below;

  • Check and confirm instruments are suitable for the certain specification requirements.
  • Check all instruments in the loop against their specification sheet. Verify it configurations against required. For Analog signals, the basic 4 – 20mA DC serves as an I/O signal, for Smart type transmitters.
  • Check that cable schedule and wiring is correct and in accordance with the wiring diagram.
  • Check hook – up and mounting is correct, and all bracket, fittings, etc, are secure
  • Check impulse lines are pressure tested, if any
  • Check the cable continuity and resistance test are complete
  • Check all power supply, voltages settings are correct before application of power
  • Check that all covers exposing dangerous voltage are secure.
  • Check that applicable MCC cubicles are in test mode
  • Check that all applicable drives, motors, etc., are locked off with padlocks.
  • Check to ensure that drives cannot be de – isolated while test are on progress.
  • Apply power to instruments one by one. Check each instruments for overheating etc., immediately following power- up.
  • Allow at least one hour for instruments to warm – up before beginning any tests or as recommended by the manufacturer.
  • When instruments have warmed – up, function check all items in the loop individually.
  • When checks on all components of the loop are satisfactory, re – complete the loop by re – connecting all the cables.
  • Loops will be tested by injecting the appropriate signal at the sensor or transmitter. For Loops which have components located some distance apart, at least 2 – persons in constant communication with each other shall be involved in testing the loop. One person, who will be responsible for simulation  of the measured variable, shall at all times remain at the measurement device in the field. The other person shall inspect all other devices in the loop and confirm that their operation is correct in response to changes in the measured variable.
  • For Loops which have a connection to the IPCS/DCS/SCADA or any Data Logger system by its graphics display and visualization, three (3) persons, in communication with each other, may be involved in the testing of the Loop. In such instances the third person shall remain in the PIS/Control Room and advise the field person of the graphical display and visualization in response to the actual injected signal from the field.
  • Loops with a controller shall be tested in two (2) parts; measurement and output. The measurement part shall be tested as above. The output shall be tested by the action of one person varying the controller output over its complete range, with the other person confirming the correct operation of the Regulating Device (for example Flow Control Valve) by observing its response to such action.
  • Upon completion of the Function checks on the Loop, the Loop Certificate shall be signed by the person charged with the responsibility for the complete test.

Main keywords for this article are Instrument Loop Folders, Non Foundation Fieldbus Loop Folder Contents, Foundation Fieldbus Loop Folder Contents, Motor Operation Loop,Loop Check Preparation.

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