Teledyne 9070 User Manual

TELEDYNE ANALYTICAL INSTRUMENTS

OXYGEN / CARBON DIOXIDE

ANALYZER / TRANSMITTER

MODEL 9070

May 1998

Getting Going Fast……

How to get your 9070 Analyzer working for you with the minimum of fuss…..

. Plug the power lead into the Analyzer and into the power point.

Turn on the power at the power point.

Screw the sample pipe onto the 1/8” Swagelok tube connector, on the right hand side of the Analyzer.

Wait 10 minutes for the oxygen sensor to get over 700°C.

The display will look like this if the Analyzer is oxygen

The display will look like this if the Analyzer is oxygen and carbon dioxide

Oxygen 20.9% Sensor Deg 720C

O2 20.9% CO2 0.0 Sensor Deg 720C

The 9070 Analyzer is now reading oxygen (and carbon dioxide if installed).

only.

Insert the hypodermic through a septum into a food pack to get a gas reading. Leave the hypodermic in the pack

for 4 to 6 seconds, or until the head space is nearly all pumped out. Don’t suck in the food product. (See question #1, in Frequently Asked Questions on the next page)

If you want to display the minimum oxygen, press the DISPLAY button until the lower line of the display reads

“Sample” like this-

Oxygen 20.9% Sample 0.68%

Lower Line

Some of the menu items that may have to be set the first time the Analyzer is used…..

Select the “Sample mode” (Setup # 26).

Continuous. When the process gas is available continuously. Eg Gas supply monitoring. Display Sample. When sampling a gas from a food pack. Fast Sample When sampling a gas from a food pack with very small head space. (<50cc)

Select the “Display Mode” (Setup # 27)

Oxygen % The oxygen will be displayed as a percentage down to 0.1%, then ppm down to 0.1ppm. Oxygen PPM The oxygen will always be displayed as parts per million. O2/CO2 % only The same as ‘Oxygen %’ with carbon dioxide also displayed. O2/CO2 %/PPM The same as ‘Oxygen PPM’ with carbon dioxide also displayed.

Select the alarm levels, if either a light or a relay contact is required if the oxygen/carbon dioxide is high/low.

Page 2 Teledyne Analytical Instruments 9070 Oxygen Analyzer

High Oxygen Setup # 39 Low Oxygen Setup # 41 Very Low Oxygen Setup # 43 High Carbon Dioxide Setup # 45 Low Carbon Dioxide Setup # 47

Select the output range for one or both output channels. ie To allow the oxygen or carbon dioxide to be

transmitted to another instrument. Channel 1, Setup # 20 to 22 eg Oxygen 0.1 to 100.0% Low Oxygen 10 to 10,000 PPM Channel 2, Setup # 23 to 25 eg Sample Oxygen Low Oxygen Carbon dioxide

Frequently Asked Questions……..

1. How do I insert the hypodermic needle into the food pack?

Cut a 1.5 cm length of the septum strip. Peal the backing tape off. Squeeze the food pack to get the gas into one place. Press the septum piece firmly onto the plastic wrapping film. Insert the hypodermic needle into the headspace through the septum without touching the food product. Leave the needle in the food pack until the pack has nearly collapsed, or at least 4 seconds for an oxygen measurement, and 6 seconds for an oxygen and carbon dioxide measurement. The septum strip will self-seal and can be re-used several times.

2. How often do I have to calibrate the Analyzer?

Oxygen – Once per year.

The 9070 uses the extremely stable zirconia oxygen sensor technology. In addition, the Analyzer automatically corrects for any drift in the Analyzer.

Carbon dioxide – Every 6 months, or for critical applications every 2 - 3 months.

The carbon dioxide sensor uses a specifically designed infra red source to increase the signal strength and reduce the effect of sensor drift. However optical measurements are not absolute measurements like the zirconia oxygen sensor, so occasional checks on a calibration gas confirm the accuracy.

3. Why are there 3 sample modes, and which one should I use?

The 9070 Analyzer can read and display the current level of oxygen and carbon dioxide, or It can pick the minimum/maximum oxygen and the maximum carbon dioxide. Use ‘Continuous’ mode if the Analyzer is to read a continuous supply of gas, such as monitoring a gas blanket over milk powder. Use either ‘Display Sample’ or ‘Fast Sample’ if the gas to be tested is in a food pack. The size of the pack will determine which of these two modes to use. Use Fast Sample if the package has less than 50cc head space. The Display Sample mode has the added advantage of displaying the oxygen and carbon dioxide levels as they change through the testing process.

4. Why does the back of the cabinet get so warm?

The zirconia oxygen sensor runs at about 720°C. The small furnace is mounted in the vented section at the back of the cabinet.

5. When should I replace the small disc filter on the hypodermic needle?

It will depend on the application, but you will know that the filter is blocked when the response time is much quicker when the filter is removed. The filters are much cheaper than the oxygen sensor. Keep spares handy.

Teledyne Analytical Instruments 9070 Oxygen Analyzer Page 3

CONTENTS

1. SPECIFICATIONS

2. DESCRIPTION

3. INSTALLATION & COMMISSIONING

4. OPERATORS FUNCTIONS - ALARMS

5. SETTING UP THE ANALYZER

6. MAINTENANCE

APPENDIX

1. OXYGEN SENSOR EMF TABLES

2. LOGARITHMIC OXYGEN SCALE

3. SAMPLE LOG PRINT OUT

4. CIRCUIT SCHEMATICS

Note: This manual includes software modifications up to Version 7.81, April 14, 1998

Neither the whole nor any part of the information contained in, or the product described in, this manual may be adapted or reproduced in any material form except with the prior written approval of Teledyne Analytical Instruments (Aust) Pty Ltd (Teledyne Analytical Instruments).

The product described in this manual and products for use with it, are subject to continuous developments and improvement. All information of a technical nature and particulars of the product and its use (including the information in this manual) are given by Teledyne Analytical Instruments in good faith. However, it is acknowledged that there may be errors or omissions in this manual. A list of details of any amendments or revisions to this manual can be obtained upon request from Teledyne Analytical Instruments Technical Enquires. Teledyne Analytical Instruments welcome comments and suggestions relating to the product and this manual.

All correspondence should be addressed to: Technical Enquires Teledyne Analytical Instruments (Aust.) Pty Ltd 16830 Chestnut Street City of Industry Phone: (626) 961 9221 CA 91749-1580 Fax: (626) 961 2538 USA

All maintenance and service on the product should be carried out by Teledyne Analytical Instruments authorised dealers. Teledyne Analytical Instruments can accept no liability whatsoever for any loss or damage caused by service or maintenance by unauthorised personnel. This manual is intended only to assist the reader in the use of the product, and therefore Teledyne Analytical Instruments shall not be liable for any loss or damage whatsoever arising from the use of any information or particulars in, or any error or omission in, this manual, or any incorrect use of the product.

Page 4 Teledyne Analytical Instruments 9070 Oxygen Analyzer

USING THIS MANUAL

The Teledyne Analytical Instruments9070 Trace Oxygen Analyzer has a variety of user-selectable functions.

They are simple to use because each selection is menu driven. For options you are not sure about, read the manual on that particular item.

Please read the safety information below and the ‘Installation’ section before connecting power to the Analyzer.

CAUTION 1

The oxygen sensor heater is supplied with mains voltage. This supply has electrical shock danger to maintenance personnel. Always isolate the Analyzer before working with the oxygen sensor.

The oxygen sensor must

The oxygen sensor which is heated to 720°C (1320°F) in this instrument can be a source of ignition in applications where fuel gases or very high oxygen percentages (above 50%) are present. For these applications, it will be necessary to provide a sampling line made of flame proof material, with adequate flashback arresters. If this configuration does not suit or if it is possible for raw fuel to come into contact with a hot oxygen sensor then the Model 9070 Analyzer with a heated sensor may be unsuitable for your application.

ALWAYS be connected to EARTH.

CAUTION 2

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SPECIFICATIONS

1.1 MODEL 9070 OXYGEN ANALYZER DESCRIPTION

1.2 DETAILED SPECIFICATIONS

1.3 ORDERING INFORMATION

1.4 MODEL SELECTION GUIDE

Page 6 Teledyne Analytical Instruments 9070 Oxygen Analyzer

SPECIFICATIONS

1.1 MODEL 9070 OXYGEN ANALYZER DESCRIPTION

The Teledyne Analytical Instruments model 9070 oxygen/carbon dioxide Analyzer/transmitter provides an integrated instrument for measurement of oxygen and carbon dioxide for food packaging and gas monitoring. The Analyzer provides local indication of oxygen/carbon dioxide, plus eight other selectable variables, including minimum sample hold level.

Two linearised 4–20 mA output signals are provided. Alarms are displayed at the Analyzer and relay contacts activate remote alarm devices every minute.

The 9070 has a keyboard for selecting the output range, display options, alarm levels, etc. The instrument is microprocessor based and all adjustments are made using the keyboard.

• Used for continuous gas sampling, food pack testing

• Simple to use

• Sensitive down to 0.1 ppm oxygen

• Displays 0.1% carbon dioxide resolution

• Automatic minimum/maximum sample detection, display and output to printer and 4–20 mA signals

• Automatic calibration of oxygen and carbon dioxide offset

• Linear output of % oxygen and carbon dioxide for recording or control

• Built in safety features

• 16 different alarm functions warn the operator of gas composition, sensor or Analyzer problems

• RS 232C/RS 485 printer/computer interface

1.2 DETAILED SPECIFICATIONS

Measuring Range

• 0.1 ppm to 100% oxygen

• 0 to 100 % carbon dioxide

Response Time

• Less than two seconds with a gas flow of 400 cc (50 scfm) per minute, oxygen

• Less than six seconds with a gas flow of 400 cc (50 scfm) per minute, carbon dioxide

Accuracy

• ±1% of actual measured oxygen value with a repeatability of ±0.5% of measured value.

• Carbon dioxide ±3%

Warm Up Time

• Fifteen minutes approximately for optimum accuracy. Useful readings are possible within 10 minutes after

switching the instrument on.

Teledyne Analytical Instruments 9070 Oxygen Analyzer Page 7

Outputs

• Two isolated linearised 4–20 mA DC outputs into 1000Ω load (max).

• RS232/485 computer/printer interface for peak oxygen/carbon dioxide value report and alarm functions.

• One common alarm relay for self diagnostic alarms

• One user selectable alarm relays for gas related alarm levels, ‘Sensor low temperature’ and ‘Calibration in

progress’.

Power

• 240/110 VAC, 50/60 Hz, 115W

Gas Connection

• 1/8’’ Swagelok tube connector

Flow Rate

• 200 - 300 cc (25-40 scfm) per minute, governed by internal pump

Environmental

• 0–50°C (32-120°F) ambient temperature

• 0–45°C (32-110°F) ambient temperature when CO2 sensor fitted

Weight

• 4.5 kg (10 lbs)

Dimensions

• 265mm x 158mm x 268mm. (9.91” x 6.22” x 10.55”)

Range of Output 1

• Field selectable from the following:

Output Selection Range

Linear oxygen 0–0.1% oxygen to 0–100.0% oxygen 0–1000ppm oxygen to 0–1,000,000ppm oxygen Low Range Linear oxygen 0–0.001% oxygen to 0–1.0% oxygen 0–10ppm oxygen to 0–10,000ppm oxygen

Range of Output 2

• Field selectable from the following:

Output Selection Zero Range Span Range

• Carbon Dioxide, 0–90% 10–100% Min span 10%

• Reducing Oxygen 10-1–10

-10

% 10-1–10

-30

In one decade steps. Min span three decades

• Oxygen sensor EMF 0–1100 mV 1000–1300 mV In 100 mV steps In 100 mV steps

• Sample Oxygen 0–0.1% 0.01–20% Min Span 0.01% 0–1000 ppm 100–20,000 ppm Min span 100 ppm

• Low oxygen 0–99.9% 0.1–100% oxygen Min span 0.1% 0-999,000 ppm 1,000-1,000,000 ppm Min span 1,000ppm

• Logarithmic Oxygen 0.1% O2 Fixed 20% O2 Fixed

Range of Indication, Upper Line

• Oxygen selectable either % O2 or ppm, and Carbon Dioxide

• Oxygen, auto ranging from 0.1 ppm to 100% O2 (always ppm below 0.1% oxygen if selected as % O2 in set-up

#27) Carbon Dioxide, 0.1 to 100.0%

•

Page 8 Teledyne Analytical Instruments 9070 Oxygen Analyzer

Indication Choice, Lower Line

Any or all of the following can be selected for lower line display:

Options:

• Oxygen Sensor EMF

• Oxygen Sensor Temperature

• Oxygen Sensor Impedance

• Sample Oxygen/Carbon Dioxide

• Ambient Temperature

• Ambient relative humidity

• Balance gas (Remaining gas after the O2 and CO2 have been subtracted)

• Date - time

• Run Hours since last service

• Date of last service

Relay Contacts

0.5A 24 VAC, 1A 36 VDC •

Mounting

• Desk top. Also available as a surface mount Analyzer with an external oxygen sensor.

1.3 ORDERING INFORMATION

Orders may be placed by submitting the following information (please number each item as below):

1. State if carbon dioxide measurement is required.

2. Minimum and maximum expected oxygen in sample (particularly the minimum value)

3. Other gas constituents (Any combustibles will consume oxygen as they are burnt on the surface of

4. If the gas is under pressure or if the gas must be extracted to the 9070 Analyzer.

5. Gas connection required (1/8’’ Swagelok is standard)

6. Supply voltage (240 or 110 VAC)

7. If auto/manual on-line oxygen gas calibration checking is required.

the sensor)

8. If surface mounting of the instrument is required or if free standing on rubber feet is preferred.

Ask your local Teledyne Analytical InstrumentsDistributor for assistance in ordering

1.4 MODEL SELECTION GUIDE

There are 3 options/models available within the 9070 range. 9070-1 Oxygen sensor only, with pump. 9070-2 Oxygen sensor only, no pump. 9070-5 Oxygen sensor and carbon dioxide sensor, with pump.

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2 DESCRIPTION

SECTION NUMBER

2.1 THE ZIRCONIA SENSOR

2.2 THE OXYGEN SENSOR ASSEMBLY

2.3 THE CARBON DIOXIDE SENSOR ASSEMBLY

2.4 THE ANALYZER

2.5 ALARMS

2.6 HEATER SUPPLY FOR THE OXYGEN SENSOR

2.7 THE OXYGEN SENSOR IMPEDANCE

2.8 AUTO CALIBRATION—ELECTRONICS

2.9 AUTO CALIBRATION CHECKING—OXYGEN SENSOR

2.10 AUTO CALIBRATION CHECKING—CARBON DIOXIDE SENSOR

2.11 RS 485/232C PORTS

2.12 AMBIENT TEMPERATURE

2.13 WATCHDOG TIMER

2.14 BACK UP BATTERY

AND RELATIVE HUMIDITY MEASUREMENTS

Page 10 Teledyne Analytical Instruments 9070 Oxygen Analyzer

DESCRIPTION

2.1 THE ZIRCONIA SENSOR

The oxygen Analyzer input is provided from a solid electrolyte oxygen sensor which contains a zirconia element and thermocouple. The sensor is designed to have a small sample of the unknown gas passed into the inside of the sensor tube, and air (20.95% oxygen) around the outside. A heater is mounted around the sensor to keep the sensor hot. The sensor construction is shown in Figure 2.1.

Thermocouple Wires

External Wire Contact

Internal electrode wire

Four-Bore Thermocouple Insulating Tubing

Alumina Tube

Heater (required only with heated probes)

Electrode Material

Ziconia Disc

Thermocouple Junction

Internal Electrode

Fig 2.1 Schematic View of a Sensor Assembly

The heater control is a time proportioning temperature controller and triac so that the thermocouple junction is controlled to between 720°C (1320°F) and 720°C.

When exposed to different oxygen partial pressures at the outside and inside of the sensor, an EMF (E) is developed which obeys the Nernst equation:

E (millivolts) =

loge

(PO2) INSIDE



) OUTSIDE

(PO



 

Where T is the temperature (K) at the zirconia disc (>650°C (>1200°F) ), R is the gas constant, F is the Faraday constant and (PO

) INSIDE and (PO2 ) OUTSIDE are the oxygen partial pressures at the inner and outer electrodes,

respectively, with the higher oxygen partial pressure electrode being positive.

If dry air at atmospheric pressure, (21 % oxygen) is used as a reference gas at the inner electrode, the following equations are obtained:

E (millivolts) = 2.154 x 10

-2

T log

) OUTSIDE

(PO

0.21

Transposing this equation

(%O

) OUTSIDE (ATM) = 0.21 EXP

-46.421E T

The 9070 transmitter solves this equation which is valid above 650°C (1200°F). The oxygen sensor heater maintains the sensor temperature at this level.

2.2 THE OXYGEN SENSOR ASSEMBLY

The oxygen sensor assembly provides a means of exposing the zirconia sensor to the atmosphere to be measured on the inside of the sensor, and maintain air as a reference gas on the outside of the sensor. A small volume, (from as little as 150 cc (20 scfm) /min) of the gas to be sampled is either pumped through the assembly at a known rate by the internal pump. The gas flow rate may also be monitored by a flow rate switch, which will cause an alarm if the rate falls below 120 cc (15 scfm) /min.

Teledyne Analytical Instruments 9070 Oxygen Analyzer Page 11

The sensor assembly also provides the means of maintaining the temperature of the sensor at 720°C (1320°F) by surrounding the sensor tube with a heater element, and measuring the temperature of the zirconia disc with a thermocouple inside the sensor. (See Figure 2.1)

2.3 THE CARBON DIOXIDE SENSOR ASSEMBLY

The carbon dioxide sensor assembly is mounted on a circuit board in the 9070 cabinet. The CO separate microprocessor to control the operation of the CO

cell, maintain calibration and provide a linear output to the

sensor PCB has a

main 9070 PCB. It has been designed to read carbon dioxide concentrations within the temperature range of 5 to 45°C (40°F to 110°F), with ambient humidity not exceeding 85% RH. A state of the art temperature compensated sensor is employed to maintain accuracy and reduce the need for calibration. The range of the CO

sensor PCB is 0 to 100%.

The 4-20 (0-20) mA output can be scaled to cover other ranges with a minimum span of 10% carbon dioxide.

The principle of operation is that of absorption of the specially designed infra red light source which is passed through an analysis cell and a thin film filter into a solid state detector. The filter is selective and passes radiation only in the carbon dioxide absorption wave band. The detector output is amplified and, with no carbon dioxide present in the cell, is balanced against a reference voltage to give a zero output voltage.

Absorption of infra red radiation by the gas in the cell reduces the detector signal, leading to a positive voltage appearing at the sensor output. The gain of the amplifier is adjusted automatically, and the signal is digitally processed. The carbon dioxide level is transferred to the main 9070 microprocessor via a digital link. Span and zero calibration can be done from the keyboard of the 9070. The response from the CO microprocessor on the CO

cell is non-linear with respect to carbon dioxide percentage, but is linearised within the

PCB.

Calibrate to ZERO & SPAN once every two months for best performance.

2.4 THE ANALYZER

The 9070 oxygen Analyzer is a microprocessor based, auto–calibrating instrument with a liquid crystal display, two 4– 20 or 0–20 mA output signals, a printer/computer port and four alarm relays with a total of 24 alarm functions.

The display will read in either % oxygen or ppm, as selected in set–up step 27. It is capable of calculating the oxygen volume from less than 0.1 ppm to 100%. The top line of the LCD is used to display the oxygen and the carbon dioxide content.

The lower line is used to display nine other variables such as sensor temperature, sensor impedance, date/time etc. The lower line is also used to display alarm messages such as sensor ‘OXYGEN NOT READY’ and ‘A/D CAL ERROR’, ‘HIGH O2’ etc.

Many of the functions are user variable (such as 4–20 mA output channel ranging), and are changed using a menu system from the keyboard. Even the one–time calibration is performed using the keypad. (See Section 2.8). The changes are then all stored in a battery-backed RAM module.

2.5 ALARMS

Refer to OPERATOR FUNCTIONS Section 4 for details on alarm functions.

2.6 HEATER SUPPLY FOR THE OXYGEN SENSOR CAUTION

The oxygen sensor heater is supplied with mains voltage. This supply has electrical shock danger to maintenance personnel. Always isolate the Analyzer before working with the oxygen sensor.

The sensor assembly must always be connected to earth.

The heater is supplied from the mains power directly, and the temperature is controlled initially at 720°C (1320°F) after turn on.

Page 12 Teledyne Analytical Instruments 9070 Oxygen Analyzer

2.7 THE OXYGEN SENSOR IMPEDANCE

The oxygen sensor impedance is a basic measurement of the reliability of the oxygen reading. An oxygen sensor with a high impedance reading will eventually produce erroneous signals. The Analyzer checks the oxygen sensor impedance every 5 minutes and if the impedance is above the maximum level for a specific temperature then the impedance alarm will be activated. Typical oxygen sensor impedance is 1 KΩ to 8 KΩ at 720°C (1320°F).

2.8 AUTO CALIBRATION - ELECTRONICS

The Analyzer input section is self calibrating. There are no adjustments. The analog to digital converter input stages are checked against a precision reference source and calibrated once every three seconds. Should the input electronics drift slightly then the drift will be automatically compensated for within the microprocessor. If a large error occurs due to an electronic fault then an ‘ADC CAL FAIL’ alarm will occur.

A one-off calibration procedure of the precision reference sources should never need to be repeated for the instrument life unless the instrument has been repaired. For a description of the calibration procedure, refer to ‘Set-up Function Details’, Section 5.5, items 6, 7 8 and 9.

The digital to analog converters or output section of the Analyzer are tested and calibrated when the AUTOCAL button is pressed, and if they are found to have an error then a ‘DAC CAL ERROR’ alarm will occur. The DAC sections are re-calibrated by pressing the ‘AUTO CAL’ button on the keyboard while in set-up mode.

All output signals will drop to 0 mA for one second period. It is suggested that a D/A re-calibration be performed after the instrument has stabilised, approximately 30 minutes after first switching on and after Setting Up The Analyzer Section 5.5, items 6, 7, 8 and 9 have been completed, and then annually.

2.9 AUTO CALIBRATION CHECKING - OXYGEN SENSOR

The calibration of the oxygen sensor is done automatically at the 20.9% (zero sensor mV), and can be checked with the on-line automatic gas calibration using a span gas.

Air, 20.9%. While the Analyzer is not doing a process gas measurement (the sample inlet pipe is sucking in air), the Analyzer can automatically trim the calibration to read 20.9% oxygen. For more details see the set-up section 5.5, number 10 & 11.

Span gas. On-line automatic gas calibration checking is not normally required, particularly if a gas sampling is being used. Where it is required however, when continuous gas monitoring is being used, the sensor can be checked for accuracy on-line. A solenoid valve can admit calibrated gas mixtures into the oxygen sensor via the solenoid valve under microprocessor control on a timed basis. For details refer to Section 3.6, (Using the Automatic Oxygen Check System). For details on setting up this facility, refer to set-up steps 30 to 37 in Section 5.5.

During sensor auto calibration checking, the Analyzer output will freeze and remain frozen for a further adjustable period, allowing the sensor time to recover and continue reading the sample gas oxygen level.

Calibration check gases may be manually admitted by pressing the ‘CAL’ buttons on the keyboard while in ‘RUN’ mode. The Analyzer output is frozen during the pressing of these buttons and immediately becomes active when the button is released. If calibration gas checking is enabled in the Set-up menu for either gas, an automatic gas cycle can be started by pressing the ‘CAL’ buttons in RUN mode. The cycle can be terminated by pressing any other button.

When using automatic calibration checking, it is important that the flow rate of both the sample gas and the calibration gas be approximately the same. To achieve this, the sample gas should not be driven directly into the Analyzer, but should use a bypass pipe ( ie. A ‘T’ pipe on the inlet to the Analyzer ) that the Analyzer can suck a sample of the calibration gas from.

2.10 AUTO CALIBRATION CHECKING - CARBON DIOXIDE SENSOR

Integrated into the 9070 Analyzer is a self checking and calibrating system for the CO

For best results when calibrating the CO

board for either span or zero, please observe the following guidelines.

Connect the zero or span gas to the inlet and allow the gas to flow for about 30 seconds before initiating a calibration sequence from the 9070 keyboard. Use the hypodermic needle to sample the calibration gas from a plastic pipe to maintain the normal use flow conditions. If a span and zero calibration is to be carried out, always start with the zero calibration first.

cell.

Teledyne Analytical Instruments 9070 Oxygen Analyzer Page 13

The zero calibration takes longer than the span calibration. The maximum time involved with a zero calibration is around 50 seconds, and for a span calibration the time is around 30 seconds. If a calibration has been unsuccessful due to an interrupted gas flow, contaminated calibration gas, or excessive temperature (ie: >50°C {>120°F} ), re-initiate the calibration from the 9070 keyboard.

Do not under any circumstances tamper with or open the CO

analysis chamber. Doing so will void the manufacturers

warranty. There are no user servicable parts inside, and any tampering will drastically reduce it’s performance and lifetime. Any Analysis chamber sent back for repair which has been tampered with will have to be replaced. If the carbon dioxide module fails, it should be sent back to the manufacturer for repair, and factory re-calibration.

In addition, there is an automatic process that uses the oxygen signal to enable an offset for the CO saved. This system ensures that the CO

cell will always read zero when air is flowing in the cell.

cell to be read and

2.11 RS 485 AND RS 232C PORT

The serial port is for connecting a printer, a data logger, or any computer with an RS 485/ 232-C port. It can be used to monitor the transmitter and process by logging the values of functions selected in step 53 of the set-up menu in Section

5.5.

The log period may be selected in step 20 for 1 to 2000 minutes for the printer mode or 5 to 1200 seconds for the data log mode. The baud rate may be set up in step 51.

The protocol for the serial port is eight data bits, one stop bit, no parity.

Alarms, including the time they occurred, will be transmitted to the printer and computer whenever they are first initiated, accepted and cleared (in the printer mode only).

If ‘Fast Sample or 'Display Sample' is selected in set-up step 26, each time a new minimum rate of oxygen is detected, this value plus date/time, will also be printed (in the printer mode only).

NOTE: The RS232 port is not available in the model 9070-5 (With carbon dioxide installed).

2.12 AMBIENT TEMPERATURE AND RELATIVE HUMIDITY MEASUREMENTS

Ambient temperature and relative humidity are measured within the Analyzer to improve the accuracy of the oxygen readings. These reading can be displayed on the lower line of the LCD (see set-up step 29), or may be logged to the printer/computer port ( see set-up step 53).

2.13 WATCHDOG TIMER

The watchdog timer is started if the microprocessor fails to pulse it within any one second period, (ie. fails to run its normal program).

The microprocessor will then be repeatedly reset until normal operation is resumed. Reset cycles are displayed by the ‘POWER’ light above the keyboard on the front panel. A steady ‘ON’ light indicates normal operation. If the program has not resumed normal operation after two attempts to reset, the common alarm relay will be activated. If a successful reset is achieved, the alarm will be cancelled and the Analyzer will continue to run normally.

2.14 BACK-UP BATTERY

The transmitter’s RAM and real-time clock are backed up by a lithium battery in the event of power failure. All set-up variables are saved and the clock is kept running for approximately ten years with the power off. The battery module should be replaced every 8 years. (It is the battery shaped device clipped in a socket labelled M1)

Page 14 Teledyne Analytical Instruments 9070 Oxygen Analyzer

INSTALLATION & COMMISSIONING

SECTION NUMBER

3.1 ANALYZER DIMENSIONS

3.2 EARTH, SHIELD AND POWER CONNECTIONS

3.3 CONNECTING THE OUTPUT CHANNELS

3.4 CONNECTING THE ALARMS

3.5 CONNECTING THE HORN RELAY

3.6 USING THE AUTOMATIC OXYGEN CHECK SYSTEM

3.7 CONNECTING THE PRINTER

3.8 CONNECTING POWER - COLD START

3.9 CONNECTING POWER - WARM START

3.10 COMMISSIONING - SET-UP MODE

3.11 RUN MODE

3.12 CHECKING THE ALARMS

3.13 THE OXYGEN SENSOR

3.14 SENSOR CALIBRATION - OXYGEN

3.15 SENSOR CALIBRATION - CARBON DIOXIDE

INSTALLATION

COMMISSIONING

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