SAER-6427

Engineering Report SAER-6427

1 July 2012

Indicator Lamp Color Scheme - Basis for Standards Requirement Document Responsibility: CSD/Electrical Systems Division

Saudi Aramco DeskTop Standards Table of Contents 1 2 3 4

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A B C D E

Previous Issue: New

Summary …………………………..………….. Scope ………………………………………..… Definitions ………………………………….…. Lamp Color Requirement ………………….... 4.1 Electrical Equipment …………………… 4.2 Process Equipment …………………….. Industry Practice …………………………...… 5.1 NFPA 79 ………………………………… 5.2 ISA SP 5.5 ………………………………. Consistency between Disciplines ……..….… Conclusion ……………………………………. References/Acknowledgement ……………...

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Appendices Extracts from Saudi Aramco Standards ....... 7 Extracts from NFPA 70 (National Electrical Code) …………………… 9 Motor starter photo …………………………. 10 Emergency Isolation Valve photo ……….... 11 Typical Consultation Request ……………... 12

Next Planned Update: TBD Page 1 of 13

Primary contact: Carlson, Ronald Wayne on 966-3-8809665 Copyright©Saudi Aramco 2012. All rights reserved.

Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

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Summary The indicator lamp color scheme requirement in the standards is perceived as being inconsistent between the electrical and process disciplines. In fact, the requirements are consistent with industry practice when consideration is given to what type of information is intended to be transmitted to the people interacting with the equipment. This SAER will explain the human-engineering and industrial basis for the different lamp color selection.

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Scope 2.1

Purpose The purpose of this SAER is to document the basis for the Saudi Aramco mandatory standards requiring the particular lamp color scheme for electrical and process equipment.

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Disclaimer Any recommendations in this SAER are not mandatory. If there is a conflict between this SAER and MSAERs, the MSAERs requirements take precedence.

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Definitions Text identified in bold font throughout this document is defined below. EIV: Emergency Isolation Valve MSAER: Mandatory Saudi Aramco Engineering Requirements. These documents are corporate mandatory documents. Examples of MSAERs are Saudi Aramco Materials System Specifications (SAMSSs), Engineering Standards (SAESs) and Standard Drawings (SASDs). SAER: Saudi Aramco Engineering Report

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

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Lamp Color Requirement Indicator lamps are provided on most electrical and process control equipment both at remote and local field stations, indoor and outdoor. They are used to provide feedback to the people that interface with the equipment as to the operating state of the equipment. The people that interface with the equipment have different responsibilities and are looking for different information. Plant Operators want feedback on whether or not equipment is operating. Electrical Operators/Technicians want feedback as to whether the equipment is safe to maintain. The term “operating” may be obvious for a pump; operating means the pump is on, moving. For more static equipment, such as an electrical circuit breaker or on-off valve the term “operating” isn’t an appropriate term. The circuit breaker or valve can be in two static states; open or closed. It isn’t obvious whether the lamp indicating color for a running pump should be the same as a closed breaker. 4.1

Electrical Equipment For electrical equipment (i.e., switchgear, controlgear, transfer switches, enclosed starters, etc.), the operators or technicians are mostly interested in whether the equipment is performing its intended function and whether it is safe to work on. Is it: - ENERGIZED. Electricity is connected to the process equipment. - DE-ENERGIZED. Electricity is disconnected from the process equipment Consequently, the industrial standards require the following lamp indicator color: - RED. Motor running, breaker closed, power on, etc. In other words, RED = DANGEROUS - GREEN. Motor stopped, breaker open, power off, etc. In other words, GREEN = SAFE

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Process and Control Equipment For process control equipment (i.e., pumps, valves, etc.), the operators or technicians are mostly interested in the operational state of the equipment. The color reflects whether or not the equipment is contributing to the normal functioning of the process.

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Consequently, the industrial standards require the following lamp indicator color: - RED: Pump stopped, heater off, isolation valve closed. (i.e., “Abnormal” Operation) - GREEN. Pump operating, heater on, isolation valve open (i.e., “Normal” Operation) On-Off valves are similar to electrical circuit breakers in that there are two distinct, static states; open and closed. Unlike a circuit breaker there is no obvious “normal/safe” position. “Normal” may be an open valve in one process situation and “abnormal” in another. The “safe” state of an EIV for example, is determined during the process safety hazard analysis (HAZOP). For example, for a normally open, fail closed EIV the normal process state would be open. For this example, a green lamp would indicate the valve is open (normal), a red lamp would indicate the valve is closed (abnormal). 5

Industry Practice Generally defined by NFPA 79 and ISA SP 5.5, extracts below: 5.1

NFPA 79 extract

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

5.2

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ISA SP 5.5 extract. Basis for Saudi Aramco Instrument and Control Convention

Consistency between Disciplines As previously stated the color scheme depends upon the type of information that the operator is expecting. Referring to below, for an electric motor for example, the operator of the motor controller or the technician is expecting the light to provide information that relates to his safety (“Safety of Persons”). Therefore, GREEN means SAFE, RED means energized or DANGER. The process operator at the field motor location is interested in the “Condition of the Process” or the “State of the Equipment”. GREEN means NORMAL, RED means FAULTY/ABNORMAL. The foundation for the perception that there is inconsistency is rooted in the assumption that energized equipment should be identified as DANGEROUS to all people, which isn’t the case. What is dangerous to the electrical technician (i.e., energized motor starter) is NORMAL to the process operators since the energized starter delivers power to drive the pump to keep his process NORMAL.

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

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Conclusion Although it may seem that the indicator color schemes used within Saudi Aramco are different between the electrical vs. process operator disciplines, the scheme is consistent with industrial practices and logical. The foundation to this perceived difference is based upon the assumption that all people that interface with the equipment in the plants require the same information. The people that interface with the equipment have different responsibilities and are looking for different information. Therefore, what may be considered a “dangerous” state to the electrical operator (e.g., closed breaker) results in a “normal” state to a process operator since the closed breaker results in the process pump running.

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References/Acknowledgement Acknowledgement to Patrick Flanders, Engineering Consultant, Process & Control Systems Department for his contribution to this report.

1 July 2012

Revision Summary New Saudi Aramco Engineering Report.

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix A Extracts from Saudi Aramco Standards 16-SAMSS-503 extract

SAES-P-116 extract

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix A – cont’d Extracts from Saudi Aramco Standards 34-SAMSS-831 extract

34-SAMSS-634 extract

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix B Extracts from NFPA 70 (National Electrical Code) 517.160(B)(1), 2011 extract

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix C Motor Starter

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix D Emergency Isolation Valve (EIV)

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

Appendix E Typical Consultation Request

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Document Responsibility: CSD/Electrical Systems Division SAER-6427 Issue Date: 1 July 2012 Next Planned Update: TBD Indicator Lamp Color Scheme - Basis for Standards Requirement

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