Teledyne 212R User Manual

Thermal Conductivity Analyzer Model 212R
INSTRUCTION MANUAL
MODEL 212R
THERMAL CONDUCTIVITY
ANALYZER
D ANGER
HIGHLY TOXIC AND OR FLAMMABLE LIQUIDS OR GASES MAY BE PRESENT IN THIS MONITORING SYSTEM. PERSONAL PROTECTIVE EQUIPMENT MAY BE REQUIRED WHEN SERVICING THIS SYSTEM. HAZARDOUS VOLTAGES EXIST ON CERTAIN COMPONENTS INTERNALLY WHICH MAY PERSIST FOR A
TIME EVEN AFTER THE POWER IS TURNED OFF AND DISCONNECTED. ONLY AUTHORIZED PERSONNEL SHOULD CONDUCT MAINTENANCE AND/OR SERVICING. BEFORE
CONDUCTING ANY MAINTENANCE OR SERVICING CONSULT WITH AUTHORIZED SUPERVISOR/MANAGER.
Teledyne Analytical Instruments
P/N M73212
11/29/07
ECO # 07-0182
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Thermal Conductivity Analyzer Model 212R
All Rights Reserved. No part of this manual may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any other language or computer language in whole or in part, in any form or by any means, whether it be electronic, mechanical, magnetic, optical, manual, or otherwise, without the prior written consent of Teledyne Analytical Instruments, 16830 Chestnut Street, City of Industry, CA 91749-
1580.
Warranty
This equipment is sold subject to the mutual agreement that it is warranted by us free from defects of material and of construction, and that our liability shall be limited to replacing or repairing at our factory (without charge, except for transportation), or at customer plant at our option, any material or construction in which defects become apparent within one year from the date of shipment, except in cases where quotations or acknowledgments provide for a shorter period. Components manufactured by others bear the warranty of their manufacturer. This warranty does not cover defects caused by wear, accident, misuse, neglect or repairs other than those performed by Teledyne or an authorized service center. We assume no liability for direct or indirect damages of any kind and the purchaser by the acceptance of the equipment will assume all liability for any damage which may result from its use or misuse.
We reserve the right to employ any suitable material in the manufacture of our apparatus, and to make any alterations in the dimensions, shape or weight of any parts, in so far as such alterations do not adversely affect our warranty.
Important Notice
This instrument provides measurement readings to its user, and serves as a tool by which valuable data can be gathered. The information provided by the instrument may assist the user in eliminating potential hazards caused by his process; however, it is essential that all personnel involved in the use of the instrument or its interface, with the process being measured, be properly trained in the process itself, as well as all instrumen­tation related to it.
The safety of personnel is ultimately the responsibility of those who control process conditions. While this instrument may be able to provide early warning of imminent danger, it has no control over process conditions, and it can be misused. In particular, any alarm or control systems installed must be tested and understood, both as to how they operate and as to how they can be defeated. Any safeguards required such as locks, labels, or redundancy, must be provided by the user or specifically requested of Teledyne at the time the order is placed.
Therefore, the purchaser must be aware of the hazardous process conditions. The purchaser is responsible for the training of personnel, for providing hazard warning methods and instrumentation per the appropriate standards, and for ensuring that hazard warning devices and instrumentation are maintained and operated properly.
Teledyne Analytical Instruments (TAI, the manufacturer of this instrument, cannot accept responsibility for conditions beyond its knowledge and control. No statement expressed or implied by this document or any information disseminated by the manufacturer or its agents, is to be construed as a warranty of adequate safety control
under the user’s process conditions.
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Teledyne Analytical Instruments
Thermal Conductivity Analyzer Model 212R
Table of Contents
1 Introduction
1.1 Method of Analysis.......................................................5
1.2 Sensitivity ....................................................................6
1.3 Stability........................................................................6
1.4 Special Consideration ................................................. 6
1.5 Physical Configuration .................................................6
2 Installation
2.1 Location .......................................................................7
2.2 Electrical Requirements & Connections ......................7
2.2.1 Primary Power ...............................................8
2.2.2 Signal Output .................................................8
2.2.3 Regulating Transf ormer..................................8
2.2.4 Completion & Inspection................................9
2.3 Gas Requirements & Connections...............................9
2.3.1 Reference Gas...............................................10
2.3.2 Zero Gas........................................................10
2.3.3 Span Gas.......................................................10
2.3.4 Installation of Cylinder Supplies ....................11
2.3.5 Sample Pressure ........................................... 11
2.3.6 Interconnecting Lines.....................................11
2.3.7 Vent Lines......................................................12
3 Startup
3.1 Preliminary...................................................................12
3.2 Reference Gas Flow....................................................13
3.3 Zero Gas Flow .............................................................13
3.4 Warmup........................................................................13
3.5 Zero Standardization ...................................................13
3.6 Span Standardization ..................................................14
3.7 Bypass.........................................................................14
3.8 Sample Mode...............................................................15
4 Routine Operation
4.1 Flowrate.......................................................................15
4.2 Supporting Gas Supplies.............................................16
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Thermal Conductivity Analyzer Model 212R
4.3 Standardization............................................................16
5 Periodic Maintenance
5.1 Heater Fan ...................................................................17
6 Troubleshooting
6.1 Preliminary...................................................................17
6.1.1 Electrical Checks...........................................17
6.1.2 Sampling System Checks..............................18
6.1.3 Summary of Preliminary Checks....................18
6.2 Loss of Zero Control.....................................................18
6.2.1 Dynamic Balance Procedure .........................19
6.3 Correct Operation.........................................................20
6.4 Incorrect Operation.......................................................21
6.4.1 Analyzer Leak Check.....................................21
6.4.2 Temperature Control Check...........................22
7 Calibration Data
7.1 Ranges ........................................................................24
7.2 Output Signal ...............................................................25
7.3 Span Setting ................................................................25
7.4 Recommended Accessory Gases................................25
7.4.1 Reference Gas...............................................25
7.4.2 Zero Gas........................................................25
7.4.3 Span Gas.......................................................26
Appendix
A Recommended 2-Year Spare Parts List .......................26
A Drawing List.................................................................27
A Specifications...................................................................... 28
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Teledyne Analytical Instruments
Thermal Conductivity Analyzer Model 212R
1. INTRODUCTION
1.1 Method of Analysis.
The Model 212R compares the thermal conductivity of a sample gas to that of a fixed composition reference gas and produces an electrical output signal that is calibrated to represent the difference between the two gases.
Due to the nonspecific nature of thermal conductivity measurement, standard gases of known composition will be required to calibrate the ana­lyzer. The accuracy of the analysis will be dependent on the accuracy to which the composition of the standard gases is known.
The measuring unit is a four element hot wire cell that forms one-half of an alternating current bridge circuit. Two of the hot wire elements are ex­posed to the sample gas, and two to the reference gas. The other half of the bridge circuit is formed by the center tapped secondary winding of a trans­former.
With reference and zero standardization gas flowing, the bridge circuit is balanced at one end of the measurement range. A span standardization gas containing a known concentration of the component of interest is then introduced into the sample path, and the resulting error signal generated by the now unbalanced bridge circuit is calibrated to represent the span gas mixture. The concentration of the component of interest in the span gas is predicated by the specified ranges of the analysis. After the instrument has been standardized the electrical error signal is directly related to the compo­nent of interest content of the sample gas.
The magnitude of the measuring bridge error signal is much too small to drive an indicating or recording instrument. A 100:1 step-up transformer, followed by an electronic amplifier stage, is utilized to amplify the error signal to an acceptable amplitude for demodulation. The signal is then conditioned appropriately to drive recording equipment.
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Thermal Conductivity Analyzer Model 212R
1.2 Sensitivity.
Differences in thermal conductivity that produce a measuring bridge error
signal of 0.25 microvolts will be sensed by the analyzer.
1.3 Stability.
Internal variables, other than the sample gas, that could produce variations in the output signal are carefully controlled by the Model 212R. Zero drift is approximately 2% of the fine range in a 24 hour period of operation; further­more, the drift is bidirectional with a properly installed analyzer and is related to gross changes in ambient temperature. The variables, both internal and external, that can affect the stability of the analyzer will be dealt with in detail in the instal­lation and trouble shooting sections of this manual.
1.4 Special Consideration.
Consideration of Using the 212R to Measure H2, or measure other compounds in H2. H2 in the gas state can be assume of one tow states, para H2, or ortho H2. Each has its own Thermal Conductivity Value. These differ by about 10% from one another.
So this must be taken into consideration when attempting to use the 212R on H2 streams.
We would recommend one consult Wikipedia.com or other sources to learn more about these two states of H2 and how the thermal conductivity of the gas stream varies with the state.
If for instance one is using pure H2 as a reference gas, and this gas is in the para state associated with cryogenic H2 recently vaporized, and this is then compared to cylinder H2 which may be in a different state, then considerable measurement errors can result.
Contact Teledyne for further guidance or information on your specific applica­tion.
1.5 Physical Configuration.
The analyzer is housed in a sheet steel case that is designed to flush mount within an equipment panel. Electrical controls, as well as an integral gas control
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Teledyne Analytical Instruments
Thermal Conductivity Analyzer Model 212R
panel, are located immediately behind a hinged front access door. The analyzer is suitable for installation in a sheltered non-hazardous area.
A recording and/or indicating device will be required to transduce the
electrical output signal into readable information.
2. INSTALLATION
2.1 Location.
The analyzer should be panel mounted in an upright position in an area that
is not exposed to the following conditions:
1. Direct sunlight.
2. Drafts of air.
3. Shock and vibration.
4. Temperatures other than that one would expect to see in
airconditioned, temperature controlled office of lab enviroment.
The 212R should not be mounted outdoors or subject temperature fluc-
tuations beyond 2 or 3 degrees.
The analyzer should be placed as close as possible, subject to the afore-
mentioned conditions, to the sample point.
Outline diagrams of both units will be found in the drawing section. After the cutout has been made in the equipment panel TAI recommends that the analyzer be used as a template to lay out the four mounting holes. Such a proce­dure will compensate for sheet metal tolerance errors.
2.2 Electrical Requirements and Connections.
Provisions have been made to accommodate the three external circuit connections required by the analyzer. Access holes on one side of the analyzer case (see Outline Diagram) are provided for the installation of the conduit and electrical wiring. All three customer connected circuits are to be terminated on the barrier terminal strip identified “TS1”.
To install the conduit and wiring, the inner horizontally hinged panel must be opened (to open the panel, turn the fastener screw at the top of the Panel a 1/4 turn ccw). While installing the conduit and wiring be careful not to disturb the foam insulation lining the interior of the case anymore than is absolutely neces­sary.
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Thermal Conductivity Analyzer Model 212R
IMPORTANT: The foam lining the interior of the analyzer is an
integral part of the environmental temperature control system. Removal or destruction of this lining will result in erratic instrument perfor­mance.
2.2.1 Primary Power.
A source of single phase, 105 to 125 volt, 60 cycle power will be required to operate the analyzer. The maximum power consumption of the analyzer is 500 watts.
NOTE: The analyzer is also available for 50 cycle operation
with special modifications and accessories.
Refer to the Interconnection Diagram in the drawing section of the manual and connect the power and ground wiring as shown. Be sure to polarize the power service connections as indicated. When connecting the wires, do not leave an excessive amount of slack within the analyzer. Two vacuum tubes are located just below the wiring area and the wiring should be installed to be well clear of them.
2.2.2 Signal Output.
Connect a two conductor shielded cable between the analyzer and record­ing equipment. Be sure to observe the proper polarity at both instruments. Connect the shield of the cable on the indicated terminal at the analyzer only, and cut back and insulate the shield at the recorder.
NOTE: Connecting the shield at both ends of a cable when
dealing with low level circuits can create a ground loop between two instruments. Improperly installed shielding can produce more noise in a low level circuit than no shielding at all.
2.2.3 Regulating Transformer.
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Thermal Conductivity Analyzer Model 212R
Run the cable attached to the transformer unit in through the access hole that is equipped with the cable clamp and terminate it as specified on the interconnection diagram.
2.2.4. Completion and Inspection.
After the electrical connections have been completed, slide any excess slack back into the conduits so that the installed wiring is not in contact with the components mounted on the analyzer chassis.
Remove the three foam strips that are taped to the inside of the analyzer door and use them to stuff the conduit openings. It is important that these openings be as well sealed as possible.
Check to see that the temperature control printed circuit board, and all vacuum tubes are firmly seated in their respective sockets.
Close and latch the control panel. There should be no further need to have access to the interior of the analyzer. All controls and adjustments are arranged so that they can be manipulated without disturbing the delicate temperature equilibrium of the instrument interior.
2.3 Gas Requirements and Connections.
Before attempting installation of the sample and supporting gas lines and accessories give careful consideration to the following important installation notes.
Note #1: It is absolutely necessary that all connections and components
in the gas control system ahead of the measuring cell be leak free. Toward that end TAI has tested the integral sampling system under pressure with a sensitive leak detector and certifies that the analyzer is leak free.
Note #2: Use no solder connections in the system. Soldering fluxes
outgas into the sample lines and produce erratic output readings. Acid type soldering fluxes actually attack and permanently change the characteristics of the detector cell measuring elements.
Note #3: All sample system tubing should be new and clean. Many
gases and vapors are absorbed by dirt or oxide coatings on tubing walls. These gases and vapors are released as the ambient temperature rises. Because of the high sensitivity of the analyzer, this absorption-desorption phenomenon can
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