Section 12 — Instruments and Controls

On-Line Analyzers

IPE Engineering Practice IPE-EP-12-7-1

Document number: IPE-EP-12-7-1 · Section: 12 — Instruments and Controls

SCOPE

The purpose of this Practice is to define the technical requirements for analyzers purchased by IPE. Specific specifications and data sheets will be attached to this Practice for all analyzers.
Any deviation from this Practice shall be approved by the procedure described in EP 1–1–3.
A revision bar indicates all changes made to this Revision.

REFERENCES

Analyzers, samples systems, and houses shall be manufactured and installed in accordance with the latest editions of the following and shall be used in conjunction with this Practice:

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1–1–3 Deviations to IPE Engineering Practices EP 12–1–1 Control Systems EP 12–7–1 DS On–Line Analyzers Data Sheet EP 12–7–2 Analyzer Shelters EP 13–2–1 Electrical Detail Design and Construction Practice
NFPA Codes
70 National Electric Code 496 Purged and Pressurized Enclosures for Electrical Equipment
APl Practices
RP 500A Classification of Locations for Electrical Installations in Petroleum Refineries RP 550 Manual on Installation of Refinery Instrument and Control Systems
ISA
S50.1 Compatibility of Analog Signals for Electronic Industrial Process Instruments

DEFINITIONS

Analyzing time - For continuous analyzer the time taken to reach 95% of a step change, i.e. 3 time constants. For cyclic analyzers the time taken to complete each cycle.
Analysis time lag - The sum of the “sample time lag” and the “analyzing time”, i.e. the time between withdrawal of sample from the process and the analysis result.
Bypass filter - A filter in which only the analyzer off take passes through the filter medium. The fast loop passes through the filter housing, acting to scour the filter element giving a self cleaning effect.
Fast loop - A sample circulating system from the process to the process, with sample usually removed via a bypass filter within the loop.
Housings - a general term covering houses, cabinets and shelters.
Inspection - An activity to check that design, materials, fabrication, and testing comply with the requirements of the specification.
Inspector - A Inflection Point Engineering, LLC appointed engineer or inspector.
Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a manufacturer by a contractor or the Owner. An indirect order is one issued to a manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.
Measuring element - Transducer or sensor which converts the measured property into a usable signal (usually electrical). Measuring elements can be mounted in–line or out–of–line via a sample system.
On–line analyzer - Applies to any analyzer used for monitoring process variables on a continuous and unattended basis in the field. Both in–line and out–of–line (using a sample system) analyzers are covered. Laboratory analyzers are not in this category, nor are environmental monitors, i.e. fire and gas detectors.
Owner - Inflection Point Engineering, LLC.
Owner’s Engineer - A Inflection Point Engineering, LLC appointed engineer.
Probe - A device for inserting into the line for the purpose of extracting a sample for use with an out of–line analyzer.
Process lag - The sum of transmission, control element and process delays, i.e. the time between change in the process and the resulting change being present at the sampling point.
Sample - The sample, fast loops or direct from process, after appropriate conditioning, e.g. filter, heating or cooling, etc.
Sample system lag - The time between withdrawal of sample from the process and its delivery to the analyzer.
Shelter - A housing with at least one side open offering only rudimentary protection from the elements. This can allow complete entry of personnel or not, depending on size and application.

System vendor - Supplier of assembled systems comprised of own and/or other equipment manufacturer’s products.

PROPOSAL DOCUMENTS

Each copy of the proposal shall include the following:

Technical data sheets for all proposed equipment. Descriptions of all analyzers and ancillary equipment. Drawing of sampling system design with material schedules.
Vendor shall quote the analysis time lag for the measurement in the system proposal.
Vendor shall specifically state maintenance reducing features and anticipated maintenance schedule in the system proposal.
Recommended spare parts list for start–up and for five years of operation with current prices and delivery for these parts.
Any written warranties covering parts and labor. The vendor shall state in the proposal the nearest service center and spare parts warehouse location for all equipment.
All cost items shall be itemized and options or alternate proposals clearly identified and itemized separately.
A user list with name and phone numbers of contacts for similar analyzer installations.
The system vendor shall submit a compliance report as part of the proposal. This report shall consist of a list of the sections contained in this Practice with the degree of compliance noted. Compliance shall be noted by “yes” for agree and accept, “Yes” with clarification or exceptions where acceptable alternatives exists, and “no” for those sections that are not met.
The vendor shall include a listing and price of any special tools, test equipment, or programming panels required to effect repairs or modifications to the system.
A warranty which states the minimum time that the analyzer will maintain and support the system.
The vendor shall state in his proposal, all utilities required, including instrument air and electrical power consumption.

QUALITY ASSURANCE

The System Vendor and Manufacturer shall operate a quality management system to ensure that the requirements of this specification are achieved. Each contractor shall state, as part of the quotation the quality assurance program and procedures used. IPE may require demonstration of the quality system.
The implementation of such a quality system is subject to monitoring by IPE and in addition may be audited following an agreed period of notice. The Inspector shall have the right to inspect at all reasonable times and at all locations during the engineering, fabrication, assembly, and testing of the analyzers, systems, cabinets, and houses.
The system vendor and manufacturer shall ensure that technical and quality requirements specified in this Practice are applied to all materials, equipment and services provided by subcontractors and to free issue materials.

GENERAL REQUIREMENTS

As a general principle, the minimum number of on–line and out–of–line analyzers necessary for this Practice should be provided.
The systems shall be designed to be operated for advanced control of plant processes. To this end, cycle time shall be minimized. Vendor shall quote the analysis time lag for the measurement listed above with the system proposal.
The systems shall be designed for minimal maintenance.
Analyzers shall satisfy all the following criteria:
Analyzers shall be single stream unless otherwise approved by the Owner’s Engineer.
Should require the minimum of ancillary sample conditioning and weather protection.
Shall incorporate all necessary features to protect against abnormal sample and services conditions.
Shall be designed for continuous operation within the limits of the specification. Routine maintenance should not be more frequent than every seven days.
Shall permit routine maintenance without opening safety enclosures.
Unless otherwise noted, analyzers shall be suitable for Class I, Group D, Division I hazardous area.
To ensure measurement of the stream property with adequate accuracy, reliability, and safety, analyzers shall be provided with all necessary sample systems, services, weather protection and ancillary equipment.
Electrical design and construction of analyzer, sample system, power sub-system, and housings shall meet the requirements of EP 13–2–1, Electrical Detail Design and Construction Practice.

SAMPLING SYSTEMS

The sampling system shall include all equipment necessary to provide the analyzer with a continuous sample representative of the process stream in respect of the property to be measured and within conditions specified for the analyzer.
The System Vendor shall furnish a complete sample conditioning system. All equipment necessary to separately condition each stream into the analyzer shall be provided. This system shall include all regulators, vaporizers, dryers, filters, rotameters, and solenoid valves required for proper analyzer operation.
The sampling system shall be designed to condition and deliver the samples with minimum dead volume and time lag.
When measuring elements are mounted in the main process line, they shall be removable without interrupting the process or creating a hazardous condition. A sample probe shall be provided when called for on the data sheets.
The sample flow–rate through each loop, by–pass and analyzer shall be indicated locally. Sample pressure (and temperature where appropriate) at the analyzer inlet shall also be indicated.
The sampling system shall include block valves on all process sample lines. All terminated lines shall be clearly labeled.

Vendor shall guarantee satisfactory operation of the analyzers and the entire sampling and analyzer system.
All multi–stream sample systems shall use a double block with atmospheric pressure bleed solenoid configuration to prevent cross–stream contamination. The Owner’s Engineer shall determine the safe location for piping the vent.
The System Vendor shall state the size of sample tubing, any filters or heaters required and transport time.
All sample system hardware shall be 300 series stainless steel unless otherwise specified by the Owner’s Engineer. Tube fittings shall be specified by the Owner’s Engineer and shall be the plant standard.
Precautions shall be taken to prevent damage to the analyzer or sample system because of abnormal plant conditions such as high temperature or high press in the process stream.
When process fluids are transported by a sample line, a valve shall be provided on each sample stream for taking a sample to check the analyzer. This point shall be close to and upstream of the analyzer, easily accessible, and arranged such that drawing the sample does not impair analyzer operation.
Facilities shall be provided for introducing calibration samples into the analyzer. The provision for introducing a test sample shall include sample containers and any necessary relief valves, pressure gauges, pressurization equipment, and sample container heating facilities.
Lines from the process connection to and including the first block valve shall meet the requirements of EP 5–2–3, Piping Standards. Other lines shall be of seamless 300 series stainless Steel tubing with compression fittings, unless otherwise approved by the Owner’s Engineer.
Liquid samples and fast loop gas samples should be returned to process unless otherwise approved by the Owner’s Engineer. Other methods of disposal shall ensure safety, freedom from pollution and minimizing sample loss, and reprocessing. Fast loops shall not be terminated in vents or drains.
Each sample isolating valve and the ends of each sample line shall be clearly labelled with the stream identity and analyzer tag number.
Sample systems shall have drains and vents as necessary to permit depressuring as a whole, or as modules, to minimize unnecessary valves and fittings. Isolation and depressuring points shall be identified on design and maintenance drawings and manuals.
Double block and bleed isolation shall be provided between the sample and all calibration, test, and flushing connections.
When walk in housings may be subjected to the presence of, or an accumulation of toxic fluids in excess of the PEL/TLV during maintenance, and samples leaks, sample lines containing the toxic fluid shall be fitted with an excess flow preventer before entry to a housing. The type shall be subject to approval by the Owner’s Engineer.

COMMUNICATION INTERFACE

When called for on the data sheets the Manufacturer should provide information on a bidirectional communication interface for the analyzer to communicate with foreign intelligent devices. This communication interface shall include:
An RS232C, serial 9600 Baud channel shall be provided. Alternate interfaces may be considered.
Communication interface shall allow a host computer or intelligent device to read sufficient information to determine the status, intermediate and final results, and operability of the analyzer. The ability to read system date and time shall be provided.
Interface shall support writing sufficient data to start, shutdown, and calibrate each stream. The ability to write and set system date and time shall be provided.
The Manufacturer shall quote as an option standard packages for communication with foreign intelligent devices via the RS232C connection. These typically take the form of programmable logic controller emulations.
The interface should be configured rather than programmed. The Manufacturer shall state the nature of the interface software. lf configurable, any tools and/or facilities needed for IPE to completely reconfigure the interface shall be provided. If custom programmed, the Manufacturer shall state the language used (FORTRAN, C, PASCAL, assembler, etc). Assembly language shall only be used when no other option exists, and shall be limited to the extent possible. If the interface can be programmed in more than one language, the vendor shall provide quotations for each language variant. Source code for custom programming shall be provided on magnetic media (IBM PC–DOS ASCII Text), as well as any nature of tool or facilities necessary for IPE to regenerate executable code from the source code and install the new executable code in the vendors equipment.
The interface shall be arranged such that it can be modified by IPE to add or delete analyzers, streams, components, or other similar changes. If this requires configuration tools and/or facilities of any type, the Manfacturer shall state explicitly what is required for the reconfiguration, shall provide a description of the reconfiguration procedure, and shall provide these configuration tools as part of the bid.
The interface device shall be self–initializing requiring no manual intervention to recover from events such as power faliures, communication line failures, or manual reset of the processing device at either end of the communication link.

CHROMATOGRAPH

All chromatographs shall have a communication and control network. The chromatograph network shall provide a connection through which a host computer or other intelligent device can read data from any analyzer on the network. The chromatograph network shall allow writing data from the host computer or intelligent device to the chromatograph controller for calibration, diagnostic, or configuration purposes. Requirements of Section 8.0 of this Practice for a communication interface shall be provided.

The chromatograph controller shall be an integral part of the analyzer needing no other devices for normal operation. It should also be capable of being linked and controlled at the analyzer site or at a remote location, such as a control room. All chromatographs shall have the capability to be connected by a data network and the failure of one unit shall not affect the operation of other units connected to the network. The Manufacturer shall supply detailed specifications and descriptions of the chromatograph network in the bid document.
Chromatograph controller shall be microprocessor based with all required functions pre– programmed. All program data tables shall be capable of field modification without user knowledge of any higher level programming. Modification capability shall be provided either locally in the field or at a central location using service panels with alpha numeric readouts. Both up and down loading of programs shall be available.
Chromatograph controller system software shall be permanently stored in non–volatile (EPROM or equivalent) memory. The use of magnetic tape or floppy disc units shall not be required. Volatile (RAM) battery backed memory is an acceptable alternative to EPROM memory.
If RAM memory is used for data and program storage, it shall be supplied with 30 day battery backup.
All processor software shall be factory installed, tested, and debugged prior to shipment and shall be shipped ready for field start–up without reprogramming or down loading from magnetic storage devices.

Visual local indication shall be provided for normal operation or fault condition.
Calibration routines shall be provided for manual initiation and day–of–week/time–of–day. Calibration gas handling system shall be included.
Manual stream control capability shall be provided.
Chromatogram data for at least three streams shall be capable of being saved.
Analysis by normalization, peak integration and peak height shall be selectable. The ability to integrate all peaks in the chromatogram should be included.
Baseline options shall include front to back gate, front gate only, back gate only, and perpendicular drop with baseline at detector zero.
Auto–gating shall be available as a standard feature. Detector balancing and auto zero shall be automatic. The controller shall provide both timed and slope gating of the detector signals.
Maintenance diagnostics shall be included in the software system to allow rapid trouble shooting in the event of system malfunction. Alarms with English language shall be provided to notify the operator in the event of analyzer malfunction.
A power interrupt feature shall be provided so that upon power interruption the analyzer shall go into backflush mode. Trend type outputs prior to power interruption shall be held until a new cycle is completed. When power is restored the system shall automatically restart without any operator attendance required.
The sample oven shall be either heat sink or electric/air convection type. The oven shall have temperature controls that will allow control of the oven temperature to values necessary for accurate chromatography. Vendor shall state oven air requirements, if any.

The Manufacturer shall state the type of detector to be used. If column switching is required, two detectors should be furnished, an intercolumn and final detector. Detector amplifier and a precision regulated power supply shall be located in the analyzer. The outputs of these detectors shall be available at the analyzer, as well as on the network devices. Column life should be a minimum of six months during normal operation.
The sample injection valve, if required, shall be sliding plate, diaphragm/piston, or linear design. Vendor to give detailed description of valve quoted with materials of construction used.
If linear valves are used, o–ring material shall be specifically stated.
If sliding plate valves are used, a metal to inert plastic mating surface design shall be used.

FTIR

Process FTIR analyzers shall be provided by Applied Automation unless otherwise approved by the Owner’s Engineer.

TOXIC GAS AND COMBUSTIBLE GAS AREA MONITORS

(*)Requirements for combustible gas area monitors shall be subject for approval by Owner’s Engineer.
(*)Requirements for Toxic Gas area monitors shall be subject for approval by Owner’s Engineer.

SERVICES

Where common utilities are shared between analyzers, they shall be capable of being isolated at each single analyzer without influencing the performance of associated analyzers.
Facilities shall be provided to prevent any dangerous situation arising in the event of coolant or cooling equipment failure. Isolation and drainage points shall be fitted to coolant systems. Pressure relief shall be provided on sample coolers.
Local indicators of pressure, temperature and flow shall be provided as necessary for monitoring satisfactory operation of the cooling system.
The Owner shall provide dry instrument air and plant air at pressures noted on data sheets. The contractor shall provide all additional filters, pressure reducing regulators and manifolds.
The power supply availability shall be specified by the Owner. Nominal power will be 120 VAC, 60 Hz.
The supplies of carrier gas and reference gas from cylinders shall have a minimum capacity of 21 days at the design rate of usage. To ensure continuity of supply, at least 2 cylinders with individual regulators and isolating valves shall be connected to a manifold. The stand–by cylinder regulator will be set to a slightly lower pressure than the manifold normal working pressure to ensure automatic operation in the event of main supply failure. Connection between cylinder and manifold shall be flexible AISI Type 316 stainless steel hose, unless otherwise specified by the Owner’s Engineer. Connections between the analyzer and manifold AISI Type 316 stainless steel tubing with Swagelok fittings, unless otherwise specified by the Owner’s Engineer.

Gas cylinders and any manifolds shall be firmly secured in racks external to enclosed premises or analyzer shelters. The racks shall be well ventilated, shaded against direct sunlight and be accessible for conveyance and replacement of cylinders.

SHELTER

The type, design and ventilation method of the analyzer shelter shall be subject to approval by the Owner’s Engineer.
Walk in shelters shall meet the requirements of EP 12–7–2, Analyzer Shelters.
(*)Toxic gas detectors shall be provided in walk in housings where personnel may be subjected to the presence of, or an accumulation of toxic gas in excess of the PEL/TLV during maintenance, and sample leaks of the analyzer system. A flashing light near the door to the house shall be provided when the PEL/TLV is exceeded. Requirements for Toxic gas detectors shall meet the approval of Owner’s Engineer.
Atmospheric sample vents shall be led to a freely ventilated point at least 3 feet above the analyzer house and at least 8 feet above any adjacent platform.

INSPECTION AND TEST

All chromatographs, distillation, boiling point, and FTIR analyzers shall be inspected and tested. Other analyzers may be tested and inspected. When not required by this Practice, the Owner’s Engineer shall specify the inspection and testing requirements on the Data Sheet.
Prior to submission to the Owner for witness test, the analyzer vendor shall provide evidence of satisfactory operation over a period of several hours on test samples, over the anticipated range of operation of the analyzer. All vendor inspection and tests shall be completed and all faults remedied.
When required, a 8–hour continuous run shall be conducted at the system vendor’s factory and witnessed by an Owner’s representative. The complete analyzer system, including recorders, transducers, programmers, interfaces, and sample system shall be tested with test samples. If there is an interruption in the test cycle due to calibration, equipment failure, or software stalls, the test shall be repeated.
Suitable samples for analyzer and system testing shall be provided by the System Vendor or Manufacturer. The Owner may provide test samples when required by the Data Sheet. Office space should be provided during the period of testing for the Inspector.

DOCUMENTATION

The documentation supplied by the vendor shall be of a coherent structure, consistent from one document to the next. Documents shall be fully indexed and cross referenced.
The issue number and date of issue of all system documentation shall be stated on each document. Changes from previous issues shall be clearly identified.
Documentation shall be provided to meet the needs of various system users, i.e. operators, engineers, maintenance technicians. Documentation may consist of a combination of published manuals and special–to–project publications.

The application engineer’s manual shall describe all the facilities required to implement and modify all the configurable system functions at all levels of application.
The maintenance technician manual shall include the following:
Equipment startup/shutdown procedures
Routine maintenance procedures
Routine preventive maintenance procedures
On–line and off–line diagnostic/testing procedures
Normal value range analog and digital indicators
Normal and trouble condition of all indicator lights
Alarm settings for all alarm points
Location of all voltage test points and nominal value
Reference to interpret the meaning of all status codes and alarms
The operator’s manual shall describe in detail the operator interface and the procedures for utilizing all his facilities for information retrieval and data entry.
A hardware manual shall include the following:
Complete bill of material for all purchased items
Design philosophy
Description of the hardware configuration
Description of operation including operation of each component board
Equipment specifications
Wiring details and I/O schedules
Details of cabinet layouts
Power supply and distribution details
Equipment drawings
Circuit diagrams for all boards
Details of all interfaces to other vendor’s equipment
Spare part information
Where the analyzer, interfaces, and ancillaries are programmable or configurable, a manual shall provide clear, complete written documentation on the following:
Design philosophy
Technical description of the software/configuration
Language in which the program is written
System flowcharts and data flow diagrams
A well annotated program/configuration listing
A description for program linkage, including activation modes, parameters passed, and termination mechanisms
A definition of data structures (internal and external) used
System utilities for documenting the contents of the system and managing its development
Software/configuration loading, backup, and downloading procedures
Software/configuration diagnostic aids, performance monitoring utilities
A list of all alarms and messages produced by the software or configuration
Initialization/restart requirements

16.0 DATA SHEET

Table 1 contains a line–by–line description of the entries required on the On–line Analyzer Data Sheet.

17.0 TABLES

TABLE 1

DATA SHEET LINE DESCRIPTIONS

Line Number	Description
1	Item no/Tag No: Unique number for application and analyzer.
1	Service: Name of stream or line; or brief description of application.
2	Flow Sheet/Drawing Ref: Use this space to reference any other documentation.
3	Analyzer Type: Examples include infrared, chromatograph, paramagnetic oxygen, or any suitable.
4	Manufacturer Name & Model: After vendor is selected enter name and model number.
7	Phase: Refers to the main body of the sample to be analyzed. It should be the condition in the process at the point of sampling.
8	Concentration units: Applies to unlabeled valves in lines 9–23.
9-23	Enter the chemical names and concentration ranges of all sample constituents, including water. Show units where different from those given in Line 8.
24-25	Contaminants: Refers to extraneous material which may adversely affect system operation. Examples: Catalyst dust, caustic or acid carryover.
26-27	Sample Source Pressure/Temperature: Conditions should be process conditions at the sample point. Extremes are important.
28-29	Slipstream Return: Also known as primary bypass. Usually provided for unconditioned sample to reduce transport time.
30-31	Sp. Gr./Viscosity: For liquids. Give Temperature if not at process conditions. Show units clearly.
32	Dew/Bubble Point: Important for condensable vapors (dew) and volatile liquids (bubble). If possible, rate at process pressure. If saturated, so state.
33	pH: For aqueous sample only.
34	Radioactive or Toxic: indicate as required. Use correct units.
35-36	Process Line/Sample Tap: Important information for sampling system design. State Material.
37	No. of Streams: Use additional form to describe sample streams that are different.
38-40
41	Condensate Removal: Indicate if removing would adversely affect the analysis. Vent/Drain discharge pressure. Indicate limits, if any, of calibration fluid flow. to: by Sample Be accurate. Many analyzers are affected variations in
42-43	Preferred Sample System Materials: Record any special materials requirements.
44	Avoid Materials: Don’t use these materials.

TABLE 1 (CONTINUED) DATA SHEET LINE DESCRIPTIONS

Line Number	Description
45	Location: System may be distributed geographically. Conditions can vary depending on location.
46	Ambient Temperature Range: Design extremes are important.
47	Indoors/Outdoors: Indoors means protection on 5 sides. If outdoors with precipitation shield, so state.
48-49	Electrical Classification: Enter “non–hazardous” or give Class, Group, and Division.
50	Enclosure Classification: Give NEMA enclosure designation.
51	NFPA Purge: The National Electrical Code (NEC) provides that purging may reduce hazardous area classification. See NFPA 496.
52	Type of Mounting: Indicate whether wall, flange, pipe, floor or other arrangement is required.
53-54	Horizontal/Elevation Distances: Required for effective design of sample transport lines.
55-56	Environmental Conditions: Check and describe if situation is significantly worse than a normal industrial environment.
57-65	Utilities: Indicate availability of utilities even though it is not expected that they will be needed.
66	Type of Operation: Manual means human operation of sequence or adjustment. Automatic means unattended operation after initial setup by an operator.
67	Location: Analyzer means at the location of the measuring device (sensor). Remote means any other location, including the control/display location.
68	Sample Switching: If more than one stream is to be monitored use this line to specify whether stream switching is to be manual at the analyzer location, manual at a remote location, or automatic. If automatic, specify the desired cycle time (time/point).
69	Calibration Fluid Switching: Similar to format in line 68.
70	Calibration Adjustments: This is the operation of setting zero and calibration span to the correct values.
71	Output Indicator: The device used to display the current value (last) of the analyzer output.
72	Alarm Contacts: If an alarm device (horn, light, etc.) is required in addition to contacts, so state. Indicate high, low or both at location desired.
73	Output Recorder: Give type, such as strip, circular, digital. Give details in lines 7980 or in additional comments.
74-75	Output Signal: Refers to transmitted analysis information. Give special interface requirements in lines 79-80 or in additional comments.
76	Signal Isolation: Refers to output signal isolation from ground. See ISA S50.1.

TABLE 1 (CONTINUED) DATA SHEET LINE DESCRIPTIONS

Line Number	Description
77	System Response Time: Give careful consideration to process and application requirements, then enter the “reasonable maximum” delay time from sample tap to analysis readout. Critical applications should show dead time and time constant separately.
78	System Maximum Allowable Error: Show the maximum allowable error that will serve actual application needs. Express in terms of =/- concentration or percent of full scale range.

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