CSBP LIMITED FOUNDATION FIELDBUS

in NAP/AN2 &PP2Plants

byVinod Verma

Presented by Ambrose Hargan

CSBP – Chems North Aerial view

Why Foundation Fieldbus (FF)Operating experience with FF in Solids Cyanide plant for 6 yearsSome Capex savings, but other additional costs as NAP/AN1 was legacy plant (spares, training to accommodate FF).

– As compared to just copying hardwired DCS design from previous plant

Field instrument diagnostics was the main attraction to enable more preventive maintenance.Phase 1: Commission the new plant with a basic installation and stabilize operation.Phase 2: set up diagnostics functionality (after commissioning) and build into maintenance systems. Can utilise “smarts” built into the design to obtain maintenance efficiencies and reduce OPEX costs in long term.

Downsides/NegativesAdditional overall design costs for Field Junction Boxes & Marshalling panels (as compared to using existing NAP/AN1 panels)

– As compared to just copying hardwired DCS design from previous plantDue to inexperience commissioning on NAP/AN1 was slow. On NAP/AN2 commissioning was easier as we had better knowledge of the process.

– Recommendation: insist on own personnel and contractors trained/experienced with fieldbus procedures

Maintenance techs took time to get used to FF-Segment checking tools , noise elimination.

– Recommendation: train personnel on fieldbus in advance, with relevant scopeNeed to consider there are multiple FF devices on a segment not just one 4-20mA. This caused a plant trip during a segment download.

– Recommendation: Use ‘partial download’ only to reconfigured devicesNoise issues experienced could have been avoided with better cable segregation.

– Recommendation: insist on contractors trained/experienced with fieldbus guidelines and close monitoring of cable laying by the Client.

I&E contractor had minimal FF experience.– Recommendation: insist on contractors trained/experienced with fieldbus

guidelinesNew plants required FF spares in addition to 4-20mA spares

– Recommendation: Minimize 4-20 mA devices to safety (SIL rated)

Other Control InformationSteam turbine/compressors/generators train used 4-20mA (vendor reluctant to use FF)

Process control system DCS host – Yokogawa Centum CS3000 could accommodate FF & 4-20mA signals

Safety System – Yokogawa Prosafe RS used 4-20mA

Motor control used Profibus DP (Siemens Simocode)

Simocode On Board Logic

I/O & FF Segment Design GuidelinesApprox 2800 hardwired IO tags in three plants.

FF 1145PB 1970 Process AIO 316Process DIO 190SIS AI 240SIS DIO 242Total 4103

Plant is Non HazardousNot more than 12 devices per segment.Not more than 3-4 control valves per segmentNon-critical temperatures routed via FF multiplexers (848T)Valve position switches hardwired to (848L) (issues with prox sensors in previous NAP/AN1).Transmitter & Control Valve are in the same segment.Dual Redundant Power Supplies HostEach segment has an advanced diagnostics PRM module to monitor segment health & performance; segment protectors in field JB’sField wiring uses Dekoron 8Pr 1.5 mm2 for trunk and 1Pr 1.5 mm2 for Spurs.

Features of Control system networkAll control system equipment in DCS Equipment room near plant

DCS host equipmentDCS marshalling panel (incl. FF segment power supplies)Dual Redundant UPS supplies

All motor control equipment in MCC RoomMotor Control Centre's (MCC’s) with Profibus DP networks 175 DrivesNetworks designed and drives allocated so that if one goes down, plant can still be run with other networksSiemens Simocode electronic, smart motor protection relaysOn-board logic in Simocodes utilized for fast control / switch on of critical drives, without delay of DCS host logic (upto 1 sec)

Central Control Room for all plant control (except PP2)

Central Control Room (Cont ..)Software Configuration Room

Engineering workstation for AN/NA plants networkYokogawa Centum CS & CS3000 (NAP/AN1 plants)Yokogawa Centum CS3000 (NAP/AN2 plants)

Engineering workstation for Ammonia plantYokogawa Centum CS & CS3000

Engineering workstation for PP2 plantYokogawa Centum CS3000

Engineering workstation for Power Management System (PMS)Running on Macroview operating system

Plant Resource Manager (PRM) – alarm, monitoring and diagnostics system. Allows direct access to instruments for maintenance and configuration. Includes Emerson Valve Link Plug-in for control valve diagnostics.P&F segment diagnostics and monitoring software for PRM.Remote DCS view software (HIS-TSE) – includes alarm management software for monitoring and reducing alarms .

Motor Control faceplates (Profibus)

Motor drive control faceplates have a lot more diagnostics information Better information for plant operatorsFirst-out cause of trip highlighted clearlyDirect access to control drawings & logic

Good Signal with no noise

Signal with noise

FF TEST/TRAINING PANEL

NAP/AN2 SEGMENTS

PP2 SEGEMENTS

Future DevelopmentContinue to develop the diagnostic alarms and monitoring features from field instruments to the DCS host.Continue to develop ValveLink software and monitoring results to control valve maintenance strategy. Set up Portable Segments to use in Field with 475’s Develop maintenance team to be more confident and proficient in diagnosis and maintenance of FF equipment/technology.Uses FF functionality to make maintenance more effective and efficient. Use “smarts” installed in system to drive maintenance towards preventive mode.