Refining
Long-Term Business Success
Reliability and Maintainability
Reliability and Maintainability
Plant-wide Automation
Application Knowledge
Lifetime Partnership
One of the most fundamental and often overlooked factors for maximizing revenue is the reliability and maintainability of automation systems. Utmost system availability is a key prerequisite for refinery uptime.
Reliability is in Our DNA
Reliability of The Production Control System
All automation suppliers take system reliability - a key factor for refinery availability - seriously. However, none matches Yokogawa in its extreme commitment. At the heart of all of the Company’s systems is the unique “Pair and Spare” controller architecture, consisting of a redundant set of CPU modules that, in turn, each contains two micro processors. The two micro processors constantly compare each other’s outputs, initiating a bump-less switchover if any mismatch is detected.
The actual availability track record of Yokogawa CENTUM VP distributed control system (DCS) reaches 99.99999% (seven 9s).
All automation suppliers take system reliability - a key factor for refinery availability - seriously. However, none matches Yokogawa in its extreme commitment. At the heart of all of the Company’s systems is the unique “Pair and Spare” controller architecture, consisting of a redundant set of CPU modules that, in turn, each contains two micro processors. The two micro processors constantly compare each other’s outputs, initiating a bump-less switchover if any mismatch is detected.
The actual availability track record of Yokogawa CENTUM VP distributed control system (DCS) reaches 99.99999% (seven 9s).

CENTUM VP : “Pair and Spare” Architecture
Reliability of Safety Instrumented System (SIS)
Yokogawa’s safety instrumented system, ProSafe-RS, is the world’s first, truly integrated safety instrumented system. Its integrated architecture with the production control system enables unified monitoring and an operation environment for the operator. TÜV Rheinland (TÜV), a German certification organization, has certified ProSafe-RS to be compliant to both IEC 61508 and IEC 61511 international standards. Additionally, TÜV has approved its use in Safety Integrity Level 3 (SIL3)*1 applications, such as Emergency ShutDown (ESD), Fire and Gas (F&G) and Boiler Management (BMS). This latest certification of IEC 61508 and IEC61511 compliance attests to the high level of Yokogawa’s technology and the quality of its safety instrumented system.
(*1) To be certified for SIL3, safety systems must be tested by a third party for a risk factor that Measures less than 1/10,000.
Yokogawa’s safety instrumented system, ProSafe-RS, is the world’s first, truly integrated safety instrumented system. Its integrated architecture with the production control system enables unified monitoring and an operation environment for the operator. TÜV Rheinland (TÜV), a German certification organization, has certified ProSafe-RS to be compliant to both IEC 61508 and IEC 61511 international standards. Additionally, TÜV has approved its use in Safety Integrity Level 3 (SIL3)*1 applications, such as Emergency ShutDown (ESD), Fire and Gas (F&G) and Boiler Management (BMS). This latest certification of IEC 61508 and IEC61511 compliance attests to the high level of Yokogawa’s technology and the quality of its safety instrumented system.
(*1) To be certified for SIL3, safety systems must be tested by a third party for a risk factor that Measures less than 1/10,000.

ProSafe-RS : SIL3 TÜV Certificate
Improving Maintainability by Diagnostic Technologies
Improved Plant Maintenance
By taking advantage of FOUNDATION fieldbus™, or HART connections with the field devices, Yokogawa’s asset management system greatly improves device maintainability that reduces maintenance costs. Now maintenance staff can gain access to field device information anywhere anytime. The system enables staff to set and modify field device parameters, and to check detailed device alarm information. Standard audit trail management allows the tracking of changes to device information.
By taking advantage of FOUNDATION fieldbus™, or HART connections with the field devices, Yokogawa’s asset management system greatly improves device maintainability that reduces maintenance costs. Now maintenance staff can gain access to field device information anywhere anytime. The system enables staff to set and modify field device parameters, and to check detailed device alarm information. Standard audit trail management allows the tracking of changes to device information.

PRM : PRM System Configuration
Device Diagnosis
With the introduction of FOUNDATION fieldbus technology and compatibility with HART, the results of field device self-diagnoses can be accurately reflected in DCS control operations. Examples of self-diagnostics include:
For even greater maintenance efficiency based on predictive maintenance, the system also provides advanced diagnostic functions. With these functions, staff can define and perform diagnostics using information from multiple devices or higher level process-dependent diagnostics. Advanced diagnosis examples include:
Yokogawa’s innovative asset management system provides all the functionality necessary for efficient maintenance of your field devices.
With the introduction of FOUNDATION fieldbus technology and compatibility with HART, the results of field device self-diagnoses can be accurately reflected in DCS control operations. Examples of self-diagnostics include:
| Valve positioner | ||
| - Signature diagnosis - Valve stick-slip diagnosis |
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| Differential pressure / pressure transmitter | ||
| - Clogging diagnosis - Orifice wearing diagnosis - Diaphragm corrosion diagnosis |
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| Temperature transmitter | ||
| - Temperature element diagnosis | ||
| Vortex flowmeter | ||
| - Clogging diagnosis - Vibration diagnosis |
For even greater maintenance efficiency based on predictive maintenance, the system also provides advanced diagnostic functions. With these functions, staff can define and perform diagnostics using information from multiple devices or higher level process-dependent diagnostics. Advanced diagnosis examples include:
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Yokogawa’s innovative asset management system provides all the functionality necessary for efficient maintenance of your field devices.

