Teledyne 4040 User Manual

INSTRUCTION, OPERATING AND

MAINTENANCE MANUAL FOR

MODEL 4040

P/N M4040

ECO: #XX-XXXX

DATE 02/22/06

DANGER

Toxic and/or flammable gases or liquids may be present in this monitoring system. Personal protective equipment may be required when servicing this instrument. 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 i

Series 4040

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 acknowledgements 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 be properly trained in the process being measured, 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, 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.

ii Teledyne Analytical Instruments

Safety Messages

Your safety and the safety of others are very important. We have provided many important safety messages in this manual. Please read these messages carefully.

A safety message alerts you to potential hazards that could hurt you or others. Each safety message is associated with a safety alert symbol. These symbols are found in the manual and inside the instrument. The definition of these symbols is described below:

Symbol

GENERAL

WARNING/CAUTION: Refer to the

instructions for details on the specific danger. These cautions warn of specific procedures which if not followed could cause bodily Injury and/or damage the instrument.

CAUTION: HOT SURFACE WARNING: This warning is

specific to heated components within the instrument. Failure to heed the warning could result in serious burns to skin and underlying tissue.

WARNING: ELECTRICAL SHOCK HAZARD: Dangerous

voltages appear within this instrument. This warning is specific to an electrical hazard existing at or nearby the component or procedure under discussion. Failure to heed this warning could result in injury and/or death from electrocution.

Technician Symbol: All operations marked with this

symbol are to be performed by qualified maintenance personnel only.

NOTE: Additional information and comments regarding

a specific component or procedure are highlighted in the form of a note.

STAND-BY: This symbol indicates that the instrument is

on Stand-by but circuits are active.

Teledyne Analytical Instruments iii

Series 4040

CAUTION: THE ANALYZER SHOULD ONLY BE USED FOR THE

PURPOSE AND IN THE MANNER DESCRIBED IN THIS MANUAL.

IF YOU USE THE ANALYZER IN A MANNER OTHER THAN THAT FOR WHICH IT WAS INTENDED, UNPREDICTABLE BEHAVIOR COULD RESULT POSSIBLY ACCOMPANIED WITH HAZARDOUS CONSEQUENCES.

This manual provides information designed to guide you through the installation, calibration and operation of your new analyzer. Please read this manual and keep it available.

Occasionally, some instruments are customized for a particular application or features and/or options added per customer requests. Please check the front of this manual for any additional information in the form of an Addendum which discusses specific information, procedures, cautions and warnings that may be specific to your instrument.

Manuals do get misplaced. Additional manuals can be obtained from Teledyne at the address given in the Appendix. Some of our manuals are available in electronic form via the internet. Please visit our website at: www.teledyne-ai.com.

iv Teledyne Analytical Instruments

Additional Safety Information

DANGER

COMBUSTIBLE GAS USAGE

This is a general purpose instrument designed for usage in a non-hazardous area. It is the customer's responsibility to ensure safety especially when combustible gases are being analyzed since the potential of gas leaks always exist.

WARNING

The customer should ensure that the principles of operating of this equipment are well understood by the user. Misuse of this product in any manner, tampering with its components, or unauthorized substitution of any component may adversely affect the safety of this instrument.

Since the use of this instrument is beyond the control of Teledyne, no responsibility by Teledyne, its affiliates, and agents for damage or injury from misuse or neglect of this equipment is implied or assumed.

WARNING: HYDROGEN GAS IS USED IN THIS INSTRUMENT AS

A FUEL. HYDROGEN IS EXTREMELY FLAMMABLE. EXTREME CARE MUST BE USED WHEN WORKING AROUND GAS MIXTURES CONTAINING FLAMMABLE GASES.

A Successful leak check was performed at TI/AI on the sample system of this instrument prior to calibration, testing and shipping. Ensure that there are no leaks in the fuel supply lines before applying power to the system.

Always purge the entire system before performing any maintenance and always leak check the system after removing any tubing or fittings on the sample

Teledyne Analytical Instruments v

Series 4040

system. See the procedures for purging and leak checking this instrument on the following pages.

If toxic gases or other hazardous materials are introduced into the sample system, the same precautions regarding leak checking and purging apply to the sample lines and sample supply or delivery lines.

WARNING: ELECTRICAL SHOCK HAZARD. WITH THE

EXCEPTION OF OPENING THE DOOR AND ADJUSTING THE PRESSURE REGULATORS, FLOW CONTROLLER, OR OBSERVING THE PRESSURE GAUGES AND THE FLOWMETER, ONLY AUTHORIZED AND SUITABLY TRAINED PERSONNEL SHOULD PERFORM WORK INSIDE OF THE INSTRUMENT. COMPONENTS WITHIN THE COVER ON THE INSIDE OF THE DOOR, INSIDE THE ISOTHERMAL CHAMBER (SAMPLE SYSTEM), AND ON THE ELECTROMETER-AMPLIFIER PC BOARD CONTAIN DANGEROUSLY HIGH VOLTAGE SUFFICIENT TO CAUSE SERIOUS INJURY OR DEATH.

There are the following three types of inaccessible

shock hazards within the Analyzer:

1. Line voltages and line related voltages such as 115 VAC which exists within the 230 VAC versions as well. These voltages stop when the Analyzer is turned off and the mains (line) cord is removed from the instrument.

2. The sensor anode supply voltage (approximately 250 VDC). This voltage exists on the Flame Guard, anode power supply, PCB, the motherboard, and the anode/igniter terminals on the sensor. THIS VOLTAGE WILL REMAIN HAZARDOUS FOR MANY MINUTES AFTER THE ANALYZER HAS BEEN TURNED OFF!

3. External hazardous voltages which may be connected to the Analyzer alarm relay connections.

vi Teledyne Analytical Instruments

Procedure for Removal of Internal Inaccessible Shock Hazards

CAUTION: SERVICING OR MAINTENANCE OF THE ANALYZER

SHOULD ONLY BE DONE BY SUITABLE TRAINED PERSONNEL. TO AVOID THESE INACCESSIBLE HAZARDOUS VOLTAGES WHEN SERVICING THE

power cord from the Analyzer.

contacts.

SERIES 4060, PERFORM EACH OF THE FOLLOWING STEPS, IN THE ORDER GIVEN, BEFORE SERVICING BEGINS:

Switch off the power to the Analyzer and remove the main (line)

Remove all external voltages from the connections to the alarm

Wait one minute.

Discharge the anode supply voltage.

a. Connect one end of an insulated (to 1000 VDC or more)

clip lead to Analyzer chassis ground (the standoff for the upper right corner of the mother PCB).

b. Put one end of a 500V rated 1000 ohm resistor in the

other end of the clip lead.

c. Check the voltage between chassis ground (the standoff

for the upper right corner of the mother PCB) and the top side of R2 at PCB number B74671. It should be between

-5VDC and +5VDC. If is in that range, the inaccessible

hazardous voltage removal procedure is completed, if not repeat steps 4.a and 4.b.

If it is absolutely necessary to work inside the instrument with power

on, use the ONE HAND RULE:

Work with one hand only.

Keep the other hand free without contacting any other object. This reduces the possibility of a ground path through the body in case of accidental contact with hazardous voltages.

WARNING: THIS INSTRUMENT IS DESIGNED TO BE OPERATED

IN A NONHAZARDOUS AREA. THE ANALYZER USES HYDROGEN GAS AND/OR OTHER COMBUSTIBLE GASES IN ITS OPERATION. THIS EQUIPMENT, IF NOT USED AND MAINTAINED PROPERLY CAN BE AN EXPLOSION HAZARD. THE ANALYZER,

Teledyne Analytical Instruments vii

Series 4040

DEPENDING ON THE APPLICATION, MAY ALSO USE TOXIC GASES. IT IS THEREFORE, THE CUSTOMER'S RESPONSIBILITY TO ENSURE THAT PROPER TRAINING AND UNDERSTANDING OF THE PRINCIPLES OF OPERATION OF THIS EQUIPMENT ARE UNDERSTOOD BY THE USER. SINCE THE USE OF THIS INSTRUMENT IS BEYOND THE CONTROL OF TELEDYNE, NO RESPONSIBILITY BY TELEDYNE, ITS AFFILIATES AND AGENTS FOR DAMAGE OR INJURY RESULTING FROM MISUSE OR NEGLECT OF THIS INSTRUMENT IS IMPLIED OR ASSUMED. MISUSE OF THIS PRODUCT IN ANY MANNER, TAMPERING WITH ITS COMPONENTS OR UNAUTHORIZED SUBSTITUTION OF ANY COMPONENT MAY ADVERSELY AFFECT THE SAFETY OF THIS INSTRUMENT.

CAUTION: WHEN OPERATING THIS INSTRUMENT, THE DOORS

MUST BE CLOSED AND ALL COVERS SECURELY FASTENED. THE GAUGES MUST BE IN PROPER WORKING ORDER. DO NOT OVERPRESSURIZE THE SYSTEM.

READ THIS MANUAL BEFORE OPERATING THE

INSTRUMENT AND ADHERE TO ALL WARNINGS INCLUDED IN THIS MANUAL.

viii Teledyne Analytical Instruments

Table of Contents

Safety Messages ..........................................................................iii

Additional Safety Information .....................................................v

Procedure for Removal of Internal Inaccessible Shock Hazards vii

List of Figures..............................................................................xii

List of Tables..............................................................................xiii

Introduction .................................................................................15

1.1 Main Features of the Analyzer 15

1.2 Principle of Operation 16

1.3 Analyzer Description 16

1.4 Applications 16

Operational Theory .....................................................................17

2.1 Introduction 17

2.2 Sample System 18

2.2.2 Input Porting 18

2.2.2 Gas Flow Control System 20

2.2.3 Fuel and Blanket Air Systems 20

2.2.4 Flame Ionization Detection Cell 20

2.3 Detection Cell 20

2.3.1 Electrometer-Amplifier 22

2.3.2 Anode Power Supply 22

2.3.3 Flame Guard Circuit 22

2.3.4 Flame Ignition Circuit 22

Installation ...................................................................................25

3.1 Unpacking the Analyzer 25

3.2 Mounting the Analyzer 25

3.3 User Connections 26

3.3.1 Electrical Power Connections 26

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Series 4040

3.3.3.1 Primary Input Power 29

3.3.3.2 Fuse Installation 29

3.3.3.3 50-Pin Equipment Interface Connector 29

3.3.3.4 Analog Output 29

3.3.3.5 Alarm Relays 30

3.3.3.6 Digital Remote Cal Inputs 32

3.3.3.7 Range ID Relays 33

3.3.3.8 Network I/O 33

3.3.3.9 Pin Out Table 33

3.3.4 RS-232 Port 35

3.3.5 Supporting Gases 35

3.3.5.2 Effluent 37

3.3.5.3 Sample Bypass Vent 37

3.3.5.4 Fuel and Air Connections 37

3.4 Placing the System in Operation 37

3.5 Activating the Support Gases 38

3.5.1 Air 38

3.5.2 Carrier Gas 38

3.5.3 Span Gas 38

3.5.4 Fuel 38

3.6 Flame Ignition 39

3.6.1 Verification of the Flame Guard Circuit 39

3.6.2 Ignition and/or Flame Guard Circuit Failure 40

3.6.3 Sample Pump 40

Operation .....................................................................................43

4.1 Analyzer Operation 43

4.2 Default Parameters 44

4.3 Style Conventions 44

4.4 Navigation and Data Entry 45

4.4.1 Arrow Keys 45

4.4.2 ENTER 45

4.4.3 ESCAPE 46

4.5 Menu Structure 47

4.5.1 Main Menus 48

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4.5.2 Expanded menus 49

4.6 Setting up an AUTO-CAL 53

4.7 Adjusting the GAIN 53

4.8 Password Protection 54

4.9 Logging Out 57

4.10 The Model Screen 58

4.11 System Self-Diagnostic Test 58

4.12 Span 59

4.13 The Alarms Function 60

4.14 The Range Function 62

4.15 Changing Stream 63

4.16 Analog output Adjustment 63

4.17 Standby 64

4.18 Advanced User Functions 65

4.18.1 Timing 65

Appendix......................................................................................67

A.1 Specifications and Initial Settings: 67 A.2 Recommended Spare Parts List 68 A.3 Drawing List 69

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Series 4040

List of Figures

Figure 1-1: 19” Rack Piping Diagram-Model 4060 .....................22

Figure 1-2: Flame Ionization Cell...................................................24

Figure 3-1: Gas Connections.........................................................27

Figure 3-2: Equipment Interface Connector Pin Arrangement.......29

Figure 4-1: Front Panel View of Regulator and Gages..................48

xii Teledyne Analytical Instruments

List of Tables

Table 3-1: Analog Output Connections .........................................30

Table 3-4: Alarm Relay Contact Pins ............................................31

Table 3-5: Remote Calibration Connections..................................32

Table 3-6: Range ID Relay Connections.......................................33

Table 3-7: Pin out of 50 pin D-Sub Connector...............................33

Table 3-8: Commands via RS-232 Input.......................................35

Table 3-9: Required RS-232 Options............................................35

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Series 4040

xiv Teledyne Analytical Instruments

Introduction

Teledyne Analytical Instruments Series 4040, Methane/ Nonmethane Analyzer, is designed to measure the quantity of variety of hydrocarbons present in the sample gas. The Analyzer is a microprocessor controlled digital instrument based on Teledyne’s highly successful Model 402R series analog Total Hydrocarbon Analyzer, coupled with a gas separation Column and a switching valve. The Analyzer allows for the separation and measurement of methane hydrocarbon from the rest of the hydrocarbons in the low ppm range.

1.1 Main Features of the Analyzer

The Analyzer is sophisticated yet simple to use. A dual display on the front panel prompts and informs the operator during all phases of operation. The main features of the analyzer include:

1. Easy-to-use front panel interface that includes a red 5-digit LED

display and a vacuum fluorescent display (VFD), driven by microprocessor electronics.

2. High resolution, accurate readings of concentration.

3. Versatile analysis with three user-definable analysis ranges.

4. Microprocessor based electronics: 8-bit CMOS microprocessor

with 32 kB RAM and 128 kB ROM.

5. Auto ranging allows analyzer to automatically select the proper

preset range for a given measurement. Manual override allows the user to lock onto a specific range of interest.

6. Two adjustable concentration alarms and a system failure alarm.

7. Extensive self-diagnostic testing at startup and on demand.

8. RS-232 serial digital port for use with a computer or other digital

communication device.

9. Analog outputs for concentration and range identification (0-1

VDC standard and isolated 4-20 mA dc).

10. Superior Accuracy

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Series 4040

1.2 Principle of Operation

The sample is brought to a heated compartment (50 - 80° C per application) and into a sample loop and a 10-port, 2 position (Position A & B) switching valve. In valve Position B the carrier gas, nitrogen, pushes the sample into a Column to separate methane from the remaining hydrocarbons. The eluted gases are analyzed for methane in the FID detector. In valve Position A, the flow through the Column is reversed and the carrier gas pushes the sample into the FID to detect NMH. The electrical output is directly proportional to the concentration of the ionizable hydrocarbons present in the sample stream.

1.3 Analyzer Description

The standard analyzer is housed in a sheet steel equipment case flush-mounted in a 19" rack. The front interface panel is mounted on a door which, when opened, allows convenient access to the Analyzer electronics. The entire front panel can slide out of the chassis to provide greater access to the electronics and to the sample system. Gas pressure and flow controls are mounted on the front panel adjacent to the LED and VFD displays and user interface.

At the rear of the instrument are ports for the introduction of air, carrier, fuel, span, and sample gas. A single 50-pin user-interface cable connector contains input/output and alarm signals available to the user. An RS-232 port is also available at the rear panel for connection to a remote computer or other digital communication device. The Analyzer is set up for either 120 VAC 60 Hz or 230 50/60 Hz operation depending on the customer’s requirements. The appropriate power cord for your unit has been shipped with this instrument.

1.4 Applications

• Monitoring the ambient air for methane/ non-methane in

chemical and petrochemical plants.

• Fugitive emission monitoring.

• Process emission gases in the chemical industry.

• Detecting trace methane/ non-methane in air.

• Detecting atmospheric pollutants.

16 Teledyne Analytical Instruments

Operational Theory Series 4040

Operational Theory

2.1 Introduction

The sample is brought to sample loop and a 10-port switching valve kept inside a heated (Temperature: 50° - 80° C per application) SAMPLE Chamber. Using a carrier gas and a microprocessor actuated switching valve, a fixed volume of sample collected in the Sample Loop, is pushed into the Column maintained at a constant temperature. The eluted gas is analyzed for methane in a FID detector. Immediately, at the end of the analysis of methane, the Valve is switched to reverse the flow through the Column, causing propane as NMH to elute and be analyzed.

Series 4040 uses a Flame Ionization Detector to sense hydrocarbons. The FID was selected based on the positive performance and extensive experience in the use of this detector in other Teledyne analyzers namely Model 402R and Model 4020. The FID has proven itself to be a rugged, stable, long life sensor giving years of trouble free operation in various applications.

A packed Column was used at a constant temperature to separate methane from the remaining non-methane hydrocarbons.

The analysis has 2 modes: Methane Mode and Non-methane Mode.

1) Methane Mode (POSITION B)

In this mode, the eluted sample from the column is fed to the FID for

the analysis of the methane content of the hydrocarbons.

2) Non-methane Mode (POSITION A)

During this mode, the FID detector is monitoring Non-methane

hydrocarbons, such as propane. At the end of the cycle, the methane

content of the sample (from Position B) is added to the NMH value

to compute THC values.

Teledyne Analytical Instruments 17

Operational Theory

The Series 4040 Analyzer is composed of three subsystems:

1. Sample System

2. Detector Cell

3. Electronic Signal Processing, Display and Control

2.2 Sample System

The Analyzer contains three (3) separate isothermal chambers controlled by individual PID temperature controllers, viewed just behind the Front Panel. The three chambers, ‘SAMPLE’, ‘FID’, and ‘COLUMN’ are described below.

The Analyzer consists of a SAMPLE Chamber containing the 10port switching valve and 2 sample loops. The Analyzer also consists of an ‘FID’ chamber containing the Flame, pressure regulators, pressure gauges and flow restrictors. The ‘COLUMN’ is housed in a separate ‘COLUMN’ enclosure and maintained at a close temperature.

2.2.2 Input Porting

The Analyzer is equipped with ports for the introduction of air, fuel, carrier gas, span, and sample gas. It is imperative that these gases are supplied at constant pressures using two stage stainless steel diaphragm gas regulators. The recommended pressure range is 30 to 60 psig. However, the Span gas should be supplied at a pressure of 20 psig to the restrictor fitting on the Span/Sample Manifold (optional) on the back of the Analyzer.

18 Teledyne Analytical Instruments

Operational Theory Series 4040

SAMPLE SPAN

SPAN/SAMPLE MANIFOLD

(OPTIONAL)

VENT

SAMPLE

SAMPLE IN

PUMP

FILTER

SAMPLE

FLOW

F-1

0.1 - 2 LPM

CARRIER IN

(N )

SENSOR VENT

(H )

AIR IN

FUEL

OUT

FLOW

- 60 C TYP) (50

FID CHAMBER

C TYP)

COLUMN

CHAMBER

(70

REG. 1

P. REG. 1

CARRIER

P. REG. 2

P. REG. 3

AIR

F.I.D.

FUEL

SENSOR

SAMPLE CHAMBER

(50 - 80 C PER

APPLICATION)

CH4 MODE

(POSITION B)

SAMPLE

LOOP #1

SAMPLE

LOOP #2

2 POSITION

10-PORT

VALVE

NMH MODE

(POSITION A)

LOOP #1

SAMPLE

LOOP #2

CONTROL

SV1

N.C.

Figure 2-1 19” Rack Piping Diagram-Model 4040

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Operational Theory

2.2.2 Gas Flow Control System

The Piping diagram is shown in Fig. 2-1. A 10 port switching valve is used to control and direct gas flows including sampling, back flush, and carrier gas. The fixed volume sample loop ensures the same volume of sample injection in the Column every cycle.

2.2.3 Fuel and Blanket Air Systems

Stable flow is achieved by maintaining a constant pressure across restrictors upstream from the cell. Each system incorporates an adjustable pressure regulator, pressure gauge, and restrictor. A flame out light is included to indicate when the flame fails. A fuel shut-off solenoid valve, mounted on the line that supplies fuel, stops the fuel flow in case of flame failure. This valve is located in line with the fuel port.

2.2.4 Flame Ionization Detection Cell

The carrier gas containing sample and fuel are combined within a tee fitting located in the isothermal chamber. The mixed gas is emitted from a burner within the sensor assembly. Blanket air is introduced into the sensor (or cell) by means of a separate fitting that is located in the base section of the assembly. The upper half of the assembly houses the anode-igniter, collector, and flame guard thermistor.

2.3 Detection Cell

The upper section of the stainless steel flame ionization cell houses the cylindrical collector electrode, the high voltage (+260 VDC) anodeigniter coil, and the sensing thermistor of the flame guard circuit (see cell cross-section Figure 2-2).

WARNING: DANGEROUS HIGH VOLTAGE EXISTS AT THE

ANODE IGNITER COIL (+260 VDC). DO NOT ATTEMPT TO DISCONNECT THE IGNITER COIL CABLE OR DISASSEMBLE ANY OF THE FLAME IONIZATION CELL COMPONENTS WITHOUT TURNING OFF THE POWER AND DISCONNECTING THE POWER CORD.

The collector is interconnected with the electrometer-amplifier PC board by a coaxial cable. Although the cable and fittings are intended for coaxial service, the cable is actually being used as a shielded singleconductor connection.

20 Teledyne Analytical Instruments

Operational Theory Series 4040

The anode-igniter, as its name implies, serves two functions. When relay K2 at PCB part number B74671 is energized, the coil becomes an electrical heating element that glows red-hot and ignites the hydrogen fuel. When relay K2 at B74671 is de-energized, the coil is connected to the +260 volt DC terminal of the anode-flame guard power supply PC board. In this configuration, the necessary potential difference is established between the coil (anode) and collector to promote ionization of the burned hydrocarbons. The coil functions as the high voltage anode in all three-range positions of the selector switch.

The thermistor acts as the sensor in the flame guard circuit. Its ambient temperature resistance is in the 100 K ohms region. When the flame is ignited, its resistance is reduced by a factor of 100. The thermistor is coupled to a semiconductor control circuit on the anodeflame guard power supply PC board, which will be described in a following section.

The cell electrodes of both the anode-igniter and flame guard thermistor are connected to the electronics chassis by means of a plug-in cable.

Figure 2-2: Flame Ionization Cell

Teledyne Analytical Instruments 21

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