Fisher FIELDVUE DVC6000 SIS Digital

1 FIELDVUEt DVC6000 SIS DigitalValve Controllers for Safety InstrumentedSystem (SIS) SolutionsThe operation of many industrial processes,especially in the chemical and oil & gas industries,involves inherent risk. Safety Instrumented Systemsare specifically designed to reduce the likelihood orthe severity of the impact of an identified event, thushelping to protect personnel, equipment, and theenvironment. These systems involve final controlelements, which are mostly held in one position andrequested to move only when an emergencysituation arises. Typical applications with SafetyInstrumented Systems involve Emergency ShutdownValves, Emergency Blow Down valves , EmergencyVenting valves , Emergency Isolation valves , CriticalOn Off valves , etc.

2 Because the final controlelement remains in one position without mechanicalmovement, the dependability of the valve is reducedbecause there is a chance it may not operatesuccessfully upon demand. This could cause apotentially dangerous condition leading to anexplosion or fire and the leaking of lethal chemicalsand gases to the Process Management offers a solution forSafety Instrumented System (SIS) valves that useFIELDVUE DVC600 SIS Digital valve controllers(see figure 1). Using the DVC6000 SIS permitspartial stroking of the valve to reduce the Probabilityof Failure on Demand (PFD) and, consequently, thepossibility of catastrophic situations. Partial strokingtests the final control element with a small amount ofvalve travel.

3 This movement is small enough not todisrupt production, but large enough to confirm thatthe valve is working. DVC6000 SIS Digital valvecontrollers also provide state of the art testingmethods, which reduce testing and maintenancetime and initial investment cost, improve systemperformance, and provide diagnostic 3 SISF igure 1. FIELDVUE DVC6030 SIS Digital Valve ControllerMounted on a Quarter Turn ActuatorFeaturesDIncreased System Availability The simpleand secure method of partial stroke testing allowsend users to perform more frequent valvemechanical movement tests. This reduces the PFDfactor. Because the test procedures are flexible, theycan be conducted at any time, providing moreassurance the system will be available upondemand.

4 In addition, continuous valve monitoringthrough Fisher ValveLinkt software providesawareness of the valve s Cost of Ownership Lower baseequipment cost with considerable reduction intesting time and a reduced manpower requirementmakes this solution economically feasible. DVC6000 SIS Digital valve controllers offer an economicProduct : DVC6000 SISD102784X012 December 2010 DVC6000 SISDVC6000 SISP roduct : DVC6000 SISD ecember 2010 2alternative to expensive pneumatic test panels andskilled personnel presently required for testingSafety Instrumented System Time Savings Remote testingcapability requires fewer maintenance inspectiontrips to the field thus saving considerable time.

5 UsingValveLink software s Batch Runner to establish anautomatic test routine can also provide increasedtime savings. Batch Runner increases efficiency byallowing you to set up a batch once, and repeatedlyrun that set of actions on different groups of Maintenance DVC6000 SISinstruments permit using ValveLink software toprovide Valve Degradation Analysis, which isimportant for critical valves in shut down may also reduce the amount of Stuck Alert While performing thepartial stroke test, if for any reason the valve isstuck, the Digital valve controller will not completelyexhaust the actuator pressure. This reduces thelikelihood that the valve will slam shut should itbecome unstuck.

6 The Digital valve controller willabort the test and set an alert indicating that thevalve is stuck. The alert is accessible via communication is availablethrough the use of ValveLink software,a portable handheld device such as a475 or 375 Field Communicator, or aHART capable host. HART capablehosts include, but are not limited to,DeltaV SISt and the non integratedMoore HART Loop Interface andMonitor (HIM).DSystem Audit Documentation UsingValveLink software provides a time and date stampon all tests and reports, which is important fordocumenting compliance with the requirements ofstatutory ValveLink software provides thecapability for comparing and interpreting +AUX E1029 THIRD PARTYSWITCH BOXF igure 2.

7 Initiate the Partial Stroke Test from a Push ButtonDPartial Stroke Testing DVC6000 SIS digitalvalve controllers allow a partial stroke test whichramps valve travel a small amount while the valve isin service and operating. Should a demand ariseduring the test, the test is overridden immediatelyand the valve moves to the safe state. The partialstroke test can reduce costly, labor intensive testingtechniques. The simplicity of this automated testallows for more frequent online testing. Morefrequent testing enhances loop availability andincreases the reliability of the initiated, the automated test moves the valveto a predetermined value then returns the valve to itsoriginal position.

8 The default value for valvemovement is 10% from its original position, but canbe custom set to any value up to 30% to meet plantsafety partial stroke test can be automaticallyscheduled and initiated by the device itself or it canbe performed Initiated Partial Stroke Testing The partialstroke test can be scheduled and initiated by anauthorized technician with ValveLink software. Thetechnician may also initiate the test by shorting theAUX Terminal with an external push button (figure2), or by using an LCP100 local control panel(shown in figure 18) or a Field the test does not require removing anyinstrument covers or being near the valve during partial stroke test can be initiated when the valveis operating at either 4 or 20 mA (point to pointmode).

9 In applications where a spurious trip is to beminimized, 4 mA is the normal operating SISP roduct : DVC6000 SISD ecember 2010 3 AUTO TEST INTERVALDETAILED SETUP > SIS / PARTIAL STROKESCHEDULERF igure 3. Configuring Partial Stroke Test using ValveLink SoftwareDevice Initiated Partial Stroke Test The partialstroke test can be scheduled by ValveLink softwareto be run by the device on a periodic SIS / Partial Stroke Auto Test Interval (figure 3) is used to configure the device toautomatically run the partial stroke test on a days,hours, minutes basis without user allows you to schedule the partial stroketest to run on a recurring daily, weekly, monthly, oryearly schedule that you specify, as shown in figure the time interval between tests for adevice initiated partial stroke test automates theprocess.

10 Data resulting from device initiated partialstroke tests is available for later viewing andanalysis using ValveLink Control of Final ControlElement When used in conjunction with a solenoidvalve, as shown in figures 10 and 13, DVC6000 SISdigitalx valve controllers provide an inherentredundant pneumatic path. Should an emergencysituation arise, the actuator pressure exhauststhrough either the solenoid valve or through thedigital valve controller, allowing the valve to move tothe safe Wiring Cost DVC6000 SISinstruments eliminate the need for positiontransmitters and separate wiring from thetransmitter. Through HART communicationsprotocol, the valve position is communicated overthe same 4 20 mA analog loop that provides thevalve control signal.