OPERATING INSTRUCTIONS FOR
Model 3290
Percent Oxygen Analyzer
DANGER
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 M64643
08/06/99
ECO # 99-0323
i
Copyright © 1999 Teledyne Analytical Instruments
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, 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.
ii
Teledyne Analytical Instruments
Contents
Introduction
1.1 Overview........................................................................ 1-1
1.2 Main Features of the Analyzer ....................................... 1-1
1.3 Front Panel Description.................................................. 1-2
1.4 Rear Panel Description.................................................. 1-3
Operational Theory
2.1 Introduction .................................................................... 2-1
2.2 Micro-Fuel Cell Sensor .................................................. 2-1
2.2.1 Principles of Operation .......................................... 2-1
2.2.2 Anatomy of a Micro-Fuel Cell................................. 2-2
2.2.3 Electrochemical Reactions .................................... 2-3
2.2.4 The Effect of Pressure............................................ 2-3
2.2.5 Calibration Characteristics ...................................... 2-4
2.3 Electronics ..................................................................... 2-5
2.3.1 General.................................................................. 2-5
2.3.2 Signal Processing .................................................. 2-5
Installation
3.1 Unpacking the Analyzer................................................. 3-1
3.2 Location and Mounting .................................................. 3-2
3.2.1 Control Unit Installation.......................................... 3-2
3.2.2 External Probe Installation..................................... 3-2
3.2.3 Installing the Micro-Fuel Cell ................................. 3-2
3.3 Electrical Connections................................................... 3-3
3.4 Gas Connections ........................................................... 3-6
3.5 Installation Checklist...................................................... 3-6
Operation
4.1 Introduction .................................................................... 4-1
4.2 Using the Function and Data Entry Buttons ................... 4-2
4.3 Setting the Analysis Ranges.......................................... 4-2
4.3.1 HI Range ............................................................... 4-2
4.3.2 LO Range .............................................................. 4-3
4.4 Setting the Alarm Setpoints............................................ 4-3
Teledyne Analytical Instruments
iii
4.4.1 Alarm 1 .................................................................. 4-3
4.4.2 Alarm 2 .................................................................. 4-3
4.4.3 Sensor Fail Alarm .................................................. 4-4
4.5 Selecting a Fixed Range or Autoranging ....................... 4-4
4.6 Calibration ..................................................................... 4-4
Maintenance
5.1 Replacing the Fuse........................................................ 5-1
5.1.1 AC Powered Units ................................................. 5-1
5.1.2 DC Powered Units ................................................. 5-2
5.2 Sensor Installation or Replacement ............................... 5-2
5.2.1 When to Replace a Sensor.................................... 5-2
5.2.2 Ordering and Handling of Spare Sensors.............. 5-3
5.2.3 Removing the Micro-Fuel Cell ............................... 5-3
5.2.4 Installing a Micro-Fuel Cell .................................... 5-3
5.2.5 Cell Warranty Conditions ....................................... 5-4
Appendix
A.1 Specifications ................................................................ A-1
A.2 Spare Parts List ............................................................. A-2
A.3 Reference Drawing........................................................ A-3
iv
Teledyne Analytical Instruments
Percent Oxygen Analyzer Introduction 1
Introduction
1.1 Overview
The Teledyne Electronic Technologies Analytical Instruments (TETAI)
Model 3290 is a microprocessor-based percent oxygen analyzer for real-time
measurement of the percent of oxygen in inert gases, or in a wide variety of gas
mixtures. It features simple operation, fast response, and a compact, rugged
construction. Typical applications of the Model 3290 are monitoring nitrogen
generators and inert gas blanketing applications.
1.2 Main Features of the Analyzer
The main features of the analyzer include:
• High resolution, accurate readings of oxygen content from 0-1 %
through 0-25 %. Large, bright, light-emitting-diode meter readout.
• Simple pushbutton controls.
• Nylon cell holder.
• Advanced Micro-Fuel Cell, for percent analysis, has a two year
warranty and an expected lifetime of four years.
• Unaffected by oxidizable gases.
• Fast response and recovery time.
• Microprocessor based electronics: 8-bit CMOS microprocessor
with on-board RAM and 16 KB ROM.
• Two user selectable ranges (from 0-1 % through 0-25 %) allow best
match to users process and equipment.
• Air-calibration range for convenient spanning at 20.9 %.
Teledyne Analytical Instruments
1-1
1 Introduction Model 3290
• Operator can select Autoranging, which allows the analyzer to
automatically select the proper preset range for a given
measurement, or he can lock the analyzer onto a single range.
• Two concentration alarms with adjustable setpoints.
• Sensor failure alarm.
• Three analog outputs: two for measurement (0–10 V dc, and
negative ground 4–20 mA dc) and one for range identification
(0-10 V dc).
• Compact and rugged Control Unit with flush-panel case. Designed
for indoor use. Front panel NEMA-4 rated.
• External Probe can be located six feet or more away, depending on
the existing electromagnetic noise level.
1.3 Front Panel Description
All controls and displays except the power switch are accessible from the
front panel. See Figure 1-1. The front panel has seven pushbutton membrane
switches, a digital meter, and an alarm indicator LED for operating the analyzer.
These features are described briefly here and in greater detail in Chapter 4,
Operation.
Figure 1-1: Front Panel
Function Keys: Seven pushbutton membrane switches are used to select
the function performed by the analyzer:
• Set HI Alarm Set the concentration ABOVE which an alarm
1-2
Teledyne Analytical Instruments
activates.
Percent Oxygen Analyzer Introduction 1
• Set LO Alarm Set the concentration BELOW which an alarm
activates.
• Set HI Range Set the high analysis range for the instrument (up
to 0-25 %).
• Set LO Range Set the low analysis range for the instrument
(down to 0-1 %).
• Span Span calibrate the analyzer.
Data Entry Keys: Two pushbutton membrane switches are used to
manually change measurement parameters of the instrument as they are displayed
on the LED meter readout:
• Up Arrow Increment values of parameters upwards as they
are displayed on the LED readout.
• Down Arrow Increment values of parameters downwards as
they are displayed on the LED readout.
Digital LED Readout: The digital display is a LED device that
produces large, bright, 7-segment numbers that are legible in any lighting
environment. It has two functions:
• Meter Readout: As the meter readout, it displays the oxygen
concentration currently being measured.
• Measurement Parameters Readout: It also displays user-
definable alarm setpoints, ranges, and span calibration point when
they are being checked or changed.
1.4 Rear Panel Description
The rear panel contains the electrical input and output connectors. Separate rear panel illustrations are shown in Figure 1-2 for the AC and DC powered
versions of the instrument. The connectors are described briefly here and in
detail in the Installation chapter of this manual.
Teledyne Analytical Instruments
1-3
1 Introduction Model 3290
1-4
Figure 1-2 Rear Panel (AC and DC versions)
• Power Connection AC version: 100–240 V ac, at 50/60 Hz.
The connector housing includes the fuse
holder and the power switch.
Fuse Holder: Replacing the fuse is
described in Chapter 5, Maintenance.
I/O Power Switch: Turns the instrument
power ON (1) or OFF (0).
• Analog Outputs 0–10 V dc concentration output.
0–10 V dc range ID (or optional overrange)
output.
4–20 mA dc concentration output, negative
ground.
• Alarm Connections HI Alarm, LO Alarm, and Sensor Failure
Alarm connections.
• External Probe Connects to the Remote Probe or remote
Analysis Unit.
Teledyne Analytical Instruments
Percent Oxygen Analyzer Introduction 1
Teledyne Analytical Instruments
1-5
1 Introduction Model 3290
1-6
Teledyne Analytical Instruments
Percent Oxygen Analyzer Operational Theory 2
Operational Theory
2.1 Introduction
The analyzer is composed of two subsystems:
1. Analysis Unit with Micro-Fuel Cell Sensor
2. Control Unit with Signal Processing, Display and Controls
The Analysis Unit is designed to accept the sample gas and direct it to the
sensitive surface of the Micro-Fuel Cell sensor. The Micro-Fuel Cell is an
electrochemical galvanic device that translates the amount of oxygen present in
the sample into an electrical current.
The Control Unit processes the sensor output and translates it into electrical
concentration, range, and alarm outputs, and a percent oxygen meter readout. It
contains a microcontroller that manages all signal processing, input/output, and
display functions for the analyzer.
2.2 Micro-Fuel Cell Sensor
2.2.1 Principles of Operation
The oxygen sensor used in the Model 3290 is a Micro-Fuel Cell designed
and manufactured by TAI. It is a sealed, disposable electrochemical transducer.
The active components of the Micro-Fuel Cell are a cathode, an anode,
and the 15% aqueous KOH electrolyte in which they are immersed. The cell
converts the energy from a chemical reaction into an electrical potential that can
produce a current in an external electrical circuit. Its action is similar to that of a
battery.
There is, however, an important difference in the operation of a battery as
compared to the Micro-Fuel Cell: In the battery, all reactants are stored within
the cell, whereas in the Micro-Fuel Cell, one of the reactants (oxygen) comes
from outside the device as a constituent of the sample gas being analyzed. The
Teledyne Analytical Instruments
2-1
2 Operational Theory Model 3290
Micro-Fuel Cell is therefore a hybrid between a battery and a true fuel cell. (All
of the reactants are stored externally in a true fuel cell.)
2.2.2 Anatomy of a Micro-Fuel Cell
The Micro-Fuel Cell is made of extremely inert plastic (which can be
placed confidently in practically any environment or sample stream). It is effectively sealed, though one end is permeable to oxygen in the sample gas. At the
permeable end a screen retains a diffusion membrane through which the oxygen
passes into the cell. At the other end of the cell is a connector. The connector
mates with a miniature phone jack that provides electrical connection to the
Control Unit.
Refer to Figure 2-1, Basic Elements of a Micro-Fuel Cell, which illustrates the following internal description.
Figure 2-1. Basic Elements of a Micro-Fuel Cell (not to scale)
At the sensing end of the cell is a diffusion membrane, whose thickness is
very accurately controlled. Near the diffusion membrane lies the oxygen sensing
element—the cathode.
The anode structure is larger than the cathode. It is made of lead and is
designed to maximize the amount of metal available for chemical reaction.
2-2
Teledyne Analytical Instruments
Percent Oxygen Analyzer Operational Theory 2
The space between the active elements is filled by a structure saturated with
electrolyte. Cathode and anode are wet by this common pool. They each have a
conductor connecting them, through some electrical circuitry, to one of the
external contacts in the connector receptacle, which is on the top of the cell.
2.2.3 Electrochemical Reactions
The sample gas diffuses through the Teflon membrane. Any oxygen in the
sample gas is reduced on the surface of the cathode by the following HALF
REACTION:
O2 + 2H2O + 4e
––
–
––
→ 4OH
––
–
––
(cathode)
(Four electrons combine with one oxygen molecule—in the presence of
water from the electrolyte—to produce four hydroxyl ions.)
When the oxygen is reduced at the cathode, lead is simultaneously oxidized
at the anode by the following HALF REACTION:
2(Pb + 2OH
––
–
––
) → 2(Pb+2 + H2O) + 4e
––
–
––
(anode)
(Two electrons are transferred for each atom of lead that is oxidized. TWO
ANODE REACTIONS balance one cathode reaction to transfer four electrons.)
The electrons released at the surface of the anode flow to the cathode
surface when an external electrical path is provided. The current is proportional
to the amount of oxygen reaching the cathode. It is measured and used to
determine the oxygen concentration in the gas mixture.
The overall reaction for the fuel cell is the SUM of the half reactions above,
or:
2Pb + O2 → 2PbO
(These reactions will hold as long as no gaseous components capable of
oxidizing lead are present in the sample. The only likely components are the
halogens—iodine, bromine, chlorine and fluorine.)
The output of the fuel cell is limited by (1) the amount of oxygen in the cell
at the time and (2) the amount of stored anode material.
In the absence of oxygen, no current is generated.
2.2.4 The Effect of Pressure
In order to state the amount of oxygen present in the sample as a percentage of the gas mixture, it is necessary that the sample diffuse into the cell under
constant pressure.
Teledyne Analytical Instruments
2-3
2 Operational Theory Model 3290
If the pressure changes, the rate that oxygen reaches the cathode through
the diffusing membrane will also increase. The electron transfer, and therefore the
external current, will increase, even though the proportion of oxygen has not
changed.
Fortunately, Dalton's Law confirms that every gas in a mixture contributes
the same pressure to the mixture that it would exert if it were alone in the same
amount in that same volume. This means that as long as the total pressure of the
sample remains constant, the mixture can change, but the diffusion of the oxygen
will be affected only by the concentration of the oxygen.
For this reason, the sample system supplying sample gas to the cell should
be designed to keep the pressure on the diffusion membrane constant.
2.2.5 Calibration Characteristics
Given that the total pressure of the sample gas at the surface of the MicroFuel Cell input is constant, a convenient characteristic of the cell is that the
current produced in an external circuit of constant impedance is directly proportional to the rate at which oxygen molecules reach the cathode, and this rate is
directly proportional to the concentration of oxygen in the gaseous mixture. In
other words it has a linear characteristic curve, as shown in Figure 2-2. Measuring circuits do not have to compensate for nonlinearities.
Figure 2-2. Characteristic Input/Output Curve for a Micro-Fuel Cell
In addition, since there is zero output in the absence oxygen, the characteristic curve has an absolute zero. The cell itself does not need to be zeroed.
2-4
Teledyne Analytical Instruments
Percent Oxygen Analyzer Operational Theory 2
2.3 Electronics
2.3.1 General
The signal processing uses an Intel microcontroller with on-board RAM
and ROM to control all signal processing, input/output, and display functions for
the analyzer. System power is supplied from a universal power supply module
designed to be compatible with most international power sources.
The power supply circuitry is on the Power Supply PCB, which is mounted
vertically, just behind the rear panel of the Control Unit.
The signal processing electronics including the temperature compensated
amplifier, microcontroller, analog to digital, and digital to analog converters are
located on the Main PCB, which is mounted vertically, just behind the front
panel of the Control Unit.
2.3.2 Signal Processing
Figure 2-3 is a block diagram of the signal processing electronics described
below.
Figure 2-3: Block Diagram of the Signal Processing Electronics
In the presence of oxygen the cell generates a current. A current to voltage
amplifier (I–E AMPL) converts this current to a voltage.
Teledyne Analytical Instruments
2-5
2 Operational Theory Model 3290
The second stage amplifier (TEMP COMP) supplies temperature compensation for the oxygen sensor output. The temperature compensation amplifier
incorporates a thermistor (THERM) that is physically located in the cell block.
The thermistor is a temperature dependent resistance that changes the gain of the
amplifier in proportion to the temperature changes in the block. This change is
inversely proportional to the change in the cell output due to the temperature
changes. As a result there is negligible net change in the signal due to temperature
changes once the sensor comes to equilibrium. See Specifications in the Appendix.
The output from the temperature compensation amplifier is sent to an
analog to digital converter (ADC), and the resulting digital concentration signal is
sent to the microcontroller.
The digital concentration signal along with input from the front panel buttons
(KEYBOARD) is processed by the microcontroller, and appropriate output
signals are directed to the display and alarm relays. The same digital information
is also sent to a 12-bit digital to analog converter (DAC) that produces the 0-10
V dc analog concentration signal and the 0-10 V dc analog range ID output. A
current to voltage converter (E–I CONV) produces the 4-20 mA dc analog
concentration signal.
2-6
Teledyne Analytical Instruments
Percent Oxygen Analyzer Installation 3
Installation
Overvoltage
Category II
Installation of the analyzer includes:
1. Unpacking the system.
2. Mounting the Control Unit, External Sample Block, and MicroFuel Cell sensor.
3. Making the electrical connections.
5. Making the gas connections.
6. Testing the installation.
CAUTIONS: Read this chapter in its entirety before installing the units.
For indoor use only.
The Sample must be free of entrained solids or water. How-
ever, a high humidity sample is ideal, since it will prevent
water loss from the cell electrolyte.
The Micro-Fuel Cell sensor electrolyte is caustic. Do not
attempt to open it. Leaking or exhausted cells should be
disposed of in accordance with local regulations. Refer to the
Material Safety Data Sheet in the Appendix.
Any damage or scarring of the delicate permeable membrane
on the sensing end of the cell will require cell replacement.
Prevent contact with membrane by any solid object.
3.1 Unpacking the Analyzer
As soon as you receive the instrument, carefully unpack and inspect
Control Unit, External Probe, and any included accessories for damage.
Immediately report any damage to the shipping agent. The analyzer is
shipped with all the materials you need to install and prepare the system for
operation.
CAUTION: Do not disturb the integrity of the cell package until the cell is to
actually be used. If the cell package is punctured and air is
permitted to enter, cell-life will be compromised.
Teledyne Analytical Instruments
3-1
3 Installation Model 3290
3.2 Location and Mounting
3.2.1 Control Unit Installation
The 3290 Control Unit is designed to be panel-mounted in a general
purpose, indoor area, away from moisture and the elements. The unit should
be installed at viewing level in a sheltered area.
CAUTION: For the DC powered version, the control unit chassis must be
isolated from the input power ground.
Refer to the Outline diagram C-64771 for the physical dimensions of
the analyzer.
3.2.2 External Probe Installation
The External Probe can be installed in the process any reasonable
distance from the Control Unit. The nominal maximum is 6 ft, but the distance can be more, depending on the level of electromagnetic noise in the
operating environment.
The standard Model 3290 includes the External Probe unit depicted in
the Final Assembly, Dwg C-64643, and the Analysis Unit (probe) Outline,
Dwg B-57335. Dimensions are also given in Specifications in the Appendix.
For special applications, the type of External Probe unit supplied may
vary depending on the specific process. With these systems, specific installation and interconnect information is given in a separate probe manual or in
an addendum to this manual depending on the model External Probe used.
The addendum will reference the specific Outline and Interconnection
Drawings in the Drawings section of this manual, and provides any other
appropriate information.
For special applications the Micro-Fuel Cell may also be of a different
type than the standard E-2 unit. If this is the case, the pertinent cell specifications will be given in the addendum.
3.2.3 Installing the Micro-Fuel Cell
A Micro-Fuel Cell is included as a separate item. It must be installed
prior to instrument use.
Also, once it is expended, or if the instrument has been idle for a
lengthy period, the Micro-Fuel Cell will need to be replaced.
To install or replace the Micro-Fuel Cell, follow the procedures in
Chapter 5, Maintenance.
3-2
Teledyne Analytical Instruments
Percent Oxygen Analyzer Installation 3
3.3 Electrical Connections
Figure 3-1 shows the two alternate Model 3290 rear panels. The difference between them is the power connections. The first illustration shows the
AC powered version, and the second illustration shows the DC powered
version. Both versions have identical connections for the External Probe, the
alarms, and for both digital and analog concentration outputs. For detailed
pinouts, see the wiring/interconnection drawings in the Drawings section at
the rear of this manual.
Figure 3-1 Rear Panel Electrical Connectors for AC and DC Units
Primary Input Power (AC version): The power cord receptacle, fuse
block and Power switch are located in the same assembly. A 6-foot, standard
AC power cord is supplied with the Control Unit. Insert the female plug end
of the power cord into the power cord receptacle.
Teledyne Analytical Instruments
3-3
3 Installation Model 3290
The universal power supply allows direct connection to any 100-240 V ac,
50/60 Hz power source. The fuse block, to the right of the power cord
receptacle, accepts a 5 × 20 mm, 0.5 A, time-lag (T) fuse. (See Fuse Re-
placement in chapter 5, Maintenance.)
The Power switch is located on the right-hand end of the power source
input receptacle assembly.
Primary Input Power (DC version): The 10–36 V dc power is
connected via the + and − terminals in the upper left corner of the panel. The
fuse receptacle, to the right of the power terminal strip, holds a 0.05 A, very
quick acting fuse. (See Fuse Replacement in chapter 5, Maintenance.)
The Power switch is located below the fuse receptacle.
WARNING: Insert the stripped tips of wires entirely into the termi-
nal blocks. Do not leave exposed wire outside of the
holes in the blocks.
CAUTION: The control unit chassis must be isolated from the grounding
system of the DC input power.
Analog Outputs: There are three DC output signal connectors with
screw terminals on the panel. There are two wires per output with the polarity noted. See Figure 3-3. The outputs are:
0–10 V % Range: Voltage rises with increasing oxygen concentration,
from 0 V at 0 percent oxygen to 10 V at full scale
percent oxygen. (Full scale = 100% of programmed
range.)
0–10 V Range ID: 03.33 V = Low Range, 06.66 V = High Range,
10 V = Air Cal Range.
4–20 mA % Range: Current increases with increasing oxygen concentra-
tion, from 4 mA at 0 percent oxygen to 20 mA at full
scale percent oxygen. (Full scale = 100% of programmed range.)
Alarm Relays: The three alarm-circuit connectors are screw terminals
for making connections to internal alarm relay contacts. There is one set of
contacts for each type of alarm. Contacts are Form C, with normally open
and normally closed contact connections capable of switching up to 0.5
ampere at 125 V ac into a resistive load.
The alarm relay circuits are designed for failsafe operation, meaning the
relays are energized during normal operation. If power fails the relays deenergize (alarms activated).
3-4
Teledyne Analytical Instruments
Percent Oxygen Analyzer Installation 3
The contact connections are indicated diagrammatically on the rear
panel as Normally Closed, Common, and Normally Open. Figure 3-2
explains how these act in failsafe operation.
Figure 3-2: Contact ID for FAILSAFE Relay Operation
The specific descriptions for each type of alarm are as follows:
HI Alarm Configured as high alarm (actuates when concentration is
above threshold). Can be set anywhere between 1 and
25 %, but must be set ABOVE the threshold set for the
LO Alarm.
LO Alarm Configured as low alarm (actuates when concentration is
below threshold). Can be set anywhere from 1 to 25 %,
but must be set BELOW the threshold set for the HI
Alarm.
Sensor Fail Actuates when the output of the Micro-Fuel Cell sensor
falls below the acceptable level.
External Probe: The receptacle for the analysis unit cable is located in
the lower left-hand corner of the rear panel. The 6-pin Minifit connector is
keyed to fit only one way into the receptacle. Do not force it in. The other
end of the cable is made of four separate wires. These should be connected
to the terminal strip on the analysis unit as follows:
Red: #1
Black: #2
Green: #3
White: #4 interchanged, but be consistent.
Refer to the Final Assembly, Dwg. C-64643.
The green and white connectors can be
}
3.4 Gas Connections
Gas connection instructions depend on the specific External Probe used
and any special requirements of the process being monitored.
Teledyne Analytical Instruments
3-5
3 Installation Model 3290
The standard Model 3290 External Probe has inlet and outlet fixtures
only. Calibration gasses must be tee'd into the sample inlet through appropriate valves. ¼ inch tube fittings are used. For metric installations, ¼ inch to 6
mm adapters are supplied.
In general, sample flow and pressure must not create significant
backpressure past the sensor. For the standard probe, 2 scfh is the nominal
recommended flowrate.
The pressure required will depend on the sampling system. When
venting into a constant pressure, such as the atmosphere, controlling input
pressure is simple. If you are venting into a system of varying pressure, then
some form of pressure regulation is required.
3.5 Installation Checklist
Before connecting the instrument to the power source and turning it on,
make sure you have:
• Correctly installed the Sample and Exhaust gas lines
• Opened the isolation valves
• Checked for leaks
• Set the sample pressure to 5–10 psig, nominal
Once the above checks have been made, you can connect to the power
source. The instrument is now ready for operation.
3-6
Teledyne Analytical Instruments
Percent Oxygen Analyzer Operation 4
Operation
4.1 Introduction
Once the analyzer has been mounted, the gas lines connected and the
electrical connections made, the Analyzer can be configured for your
application. This involves setting the system parameters:
• Defining the user selectable analysis ranges.
• Setting alarm setpoints.
• Calibrating the instrument.
All of these functions are performed via the front panel controls,
shown in Figure 4-1.
Analyzing for the percent oxygen level in the gas passing through the
cell block is the default mode of operation. As long as no front panel
buttons are being pressed the Analyzer is analyzing.
Figure 4-1: Front Panel Controls and Indicators
Teledyne Analytical Instruments
4-1
4 Operation Model 3290
4.2 Using the Function and Data Entry Buttons
When no buttons on the Analyzer are being pressed, the instrument is
in the Analyze mode. It is monitoring the percent of oxygen in the sample
gas that is flowing through the Remote Probe.
When one of the Function Buttons is being pressed, the Analyzer is in
the Setup mode or the Calibration mode.
The 4 Setup function buttons on the analyzer are:
• SET ALARM 1
• SET ALARM 2
• SET HI RANGE
• SET LO RANGE
The Calibration mode button is:
• SPAN
The Data Entry buttons (∆ and ∇) increment the values displayed on
the PERCENT OXYGEN meter while one of the Function buttons is being
held down.
• ∆ : Increments the displayed value upwards.
• ∇ : Increments the displayed value downwards.
Any of the functions can be selected at any time by holding down the
appropriate button.
Each function will be described in the following sections. Although
the operator can use any function at any time, the order chosen in this
manual is appropriate for an initial setup.
4.3 Setting the Analysis Ranges
The two user definable analysis ranges are both capable of being
adjusted for from 0-1% to 0-25% oxygen concentration. Whatever values
are selected, the analyzer automatically switches from the LO range to the
HI range when the oxygen concentration reaches 100% of the LO range
fullscale value, and it switches back to the LO range when the oxygen
concentration reaches 85% of the LO range fullscale value
Note: The HI Range setpoint MUST be set at a higher concentration
percentage than the LO Range setpoint.
4.3.1 HI Range
Setting the HI Range fullscale value defines the LEAST sensitive
analysis range to be used. To set the HI Range:
4-2
Teledyne Analytical Instruments
Percent Oxygen Analyzer Operation 4
1. Press the SET HI RANGE Function button once.
2. Immediately (within 5 seconds) press either the ∆ or ∇ button
to raise or lower the displayed value, as required, until the
display reads the desired fullscale percent concentration.
4.3.2 LO Range
Setting the LO Range fullscale value defines the MOST sensitive
range to be used. To set the LO Range:
1. Press the SET LO RANGE Function button once.
2. Immediately (within 5 seconds) press either the ∆ or ∇ button
to raise or lower the displayed value, as required, until the
display reads the desired fullscale percent concentration.
4.4 Setting the Alarm Setpoints
The alarm setpoints can be adjusted over the full range of the analyzer
(0-25% oxygen content). They are set as a percent of oxygen content, so
that an alarm set to indicate 9.6 on the display will activate at 9.6% O2 on
any O2 range.
Note: The HI Alarm setpoint MUST be set at a higher concentration per-
centage than the LO Alarm setpoint.
4.4.1 Set Alarm 1
Setting the HI Alarm sets the value ABOVE which the HI Alarm will
activate. To Set the HI Alarm:
1. Press the SET HI ALARM Function button once.
2. Immediately (within 5 seconds) press either the ∆ or ∇ button
to raise or lower the displayed value, as required, until the
display reads the desired percent concentration.
4.4.2 Set Alarm 2
Setting the LO Alarm sets the value BELOW which the LO alarm
will activate. To set the LO Alarm:
1. Press the SET LO ALARM Function button once.
2. Immediately press either the ∆ or ∇ button to raise or lower the
displayed value, as required, until the display reads the desired
percent concentration.
Teledyne Analytical Instruments
4-3
4 Operation Model 3290
4.4.3 Sensor Fail Alarm
The SENSOR FAIL alarm is factory set to a reading less than 0.05%
O2. Should this alarm trigger the ALARM Indicator below the SET
Function buttons will blink, and the alarm relay contact dedicated to this
function will change state.
4.5 Selecting a Fixed Range or Autoranging
The Model 3290 can operate in fixed high, fixed low, or autoranging
mode. To change modes:
1. Press and then release the SET HI RANGE and the SET LO
RANGE buttons simultaneously.
2. Immediately (within 5 seconds) press either the ∆ or ∇ button
until Auto, Lo, or Hi displays on the LCD, as desired.
After about three seconds, the analyzer resumes monitoring in the
selected range mode.
4.6 Calibration
Preliminary—If not already done: Power up the Analyzer and
allow the LED reading to stabilize. Set the Alarm setpoints and
the fullscale ranges to the desired values.
Procedure:
1. Expose the sensor to ambient air or instrument grade air (20.9%
oxygen). Allow time for the sampling system to purge and the
analyzer to achieve equilibrium.
Note: If the analyzer goes overrange, the display will go blank and the
front panel ALARM Indicator, beneath the SET Function buttons,
will blink. Hold down the SPAN button until the ALARM Indicator
stops blinking.
2. Press the SPAN button once.
3. Immediately (within 5 seconds) press either the ∆ or ∇ button
until the display is stable and reads 20.9%.
The unit is now calibrated.
Note: The alarms will be disabled for about 25 seconds after the SPAN
button is released. Disabling the alarms allows air to be purged
from the sample system without tripping any alarm set below span
(20.9%). Do not attempt to adjust any alarm setpoints while the
alarms are disabled during the 25-second period.
4-4
Teledyne Analytical Instruments
Percent Oxygen Analyzer Maintenance 5
Maintenance
Overvoltage
Category II
Aside from normal cleaning and checking for leaks at the gas connections,
the Model 3290 should not require any maintenance beyond replacement of
expended Micro-Fuel Cells, and perhaps a blown fuse. Routine maintenance
includes occasional recalibration, as described in chapter 4, Operation.
5.1 Replacing the Fuse
5.1.1 AC Powered Units
When a fuse blows, check first to determine the cause, then replace the
fuse using the following procedure:
1. Disconnect the AC power and place the power switch located on
the rear panel in the O position. Remove the power cord from the
receptacle.
2. The fuse receptacle is located in the power cord receptacle
assembly in the upper left-hand corner of the rear panel. See Figure
5-1.
Figure 5-1: AC Fuse Replacement
3. Insert a small flat-blade screwdriver into the slot in the receptacle
wall nearest the fuse and gently pry open the fuse receptacle. The
fuse holder will slide out. The fuse in use is visible in the clip. To
open the spare fuse compartment, push on one end until it slides out.
Teledyne Analytical Instruments
5-1
5 Maintenance Model 3290
4. Remove the bad fuse and replace it with a 5×20 mm 0.5 A,
250 V ac, time lag (T) fuse (P/N F1128) for AC units.
5. Replace the fuse holder into its receptacle, pushing in firmly until it
clicks.
5.1.2 DC Powered Units
In units with DC power, the fuse is located on the rear panel above the
ON/OFF switch.
1. Open the fuse holder by unscrewing and removing the cap marked
FUSE.
2. The fuse is located inside the receptacle, not inside the cap. Both
terminals are on the same end of the fuse. Pull straight out without
twisting to remove the old fuse from the receptacle, and replace it
with a 0.5 A, 125 V dc, very quick acting (FF) microfuse (P/N
F51).
3. Replace the cap by screwing it back into the receptacle.
5.2 Sensor Installation or Replacement
5.2.1 When to Replace a Sensor
The characteristics of the Micro-Fuel Cell show an almost constant output
through their useful life, and then fall off sharply towards zero at the end. You will
find that very little adjustment will be required to keep the analyzer calibrated
properly during the duration of a given cell’s useful life.
If the sample being analyzed has a low oxygen concentration, cell failure
will probably be indicated by the inability to properly calibrate the analyzer. If
large adjustments are required to calibrate the instrument, or calibration cannot
be achieved within the range of the ∆∇ buttons, the cell may need replacing.
Read the section Cell Warranty Conditions, below, before replacing the cell.
In addition, if the front panel Percent Oxygen Meter displays “00.0” when
the unit is plugged in, and the power switch is in the ON position, the sensor
needs to be replaced.
IMPORTANT: After replacing the Micro-Fuel Cell, the analyzer must be
recalibrated. See
Calibration
in chapter 4.
5-2
Teledyne Analytical Instruments
Percent Oxygen Analyzer Maintenance 5
5.2.2 Ordering and Handling of Spare Sensors
To have a replacement cell available when it is needed, TAI recommends
that one spare cell be purchased shortly after the instrument is placed in service,
and each time the cell is replaced.
CAUTION: Do not stockpile cells. The warranty period starts on the day of
shipment. For best results, order a new spare cell when the
current spare is installed.
The spare cell should be carefully stored in an area that is not subject to
large variations in ambient temperature (75° F nominal), and in such a way as to
eliminate the possibility of incurring damage.
CAUTION: Do not disturb the integrity of the cell package until the cell is to
actually be used. If the cell package is punctured and air is permitted to enter, cell-life will be compromised.
WARNING: The sensor used in the Model 3290 uses electrolytes which
contain substances that are extremely harmful if touched,
swallowed, or inhaled. Avoid contact with ANY fluid or
powder in or around the unit. What may appear to be plain
water could contain one of these toxic substances. In case
of eye contact, immediately flush eyes with water for at
least 15 minutes. Call physician. (See Appendix, Material
Safety Data Sheet—MSDS).
5.2.3 Removing the Micro-Fuel Cell
To remove a spent or damaged Micro-Fuel Cell:
1. Disconnect the Power Source from the Unit.
2. Unplug the connector from the spent cell.
3. Remove the spent cell by unscrewing it, counterclockwise, from the
cell block.
4. Dispose of the cell in a safe manner, and in accordance with local
laws.
5.2.4 Installing a Micro-Fuel Cell
To install a new Micro-Fuel Cell:
CAUTION: Do not scratch, puncture, or damage the sensing membrane of the
Micro-Fuel Cell sensor. Damage to the membrane will require
replacement of the sensor.
1. Disconnect the Power Source from the Unit.
Teledyne Analytical Instruments
5-3
5 Maintenance Model 3290
2. Remove the new Micro-Fuel Cell from its protective bag, being
careful not to lose the O-ring at the base of the threaded portion of
the cell.
3. Replace the cell on the cell holder by screwing it clockwise into the
cell block until it is held firmly in the socket.
4. Insert the cell block electrical connector plug into the socket in the
sensor.
5.2.5 Cell Warranty Conditions
The Class E-2 Micro-Fuel cell is used in the Model 3290. This cell is a
long life cell and is warranted for 2 years (under specified operating conditions—
see Appendix) from the date of shipment. Note any Addenda attached to the
front of this manual for special information applying to your instrument.
With regard to spare cells, warranty period begins on the date of shipment.
The customer should stock only one spare cell per instrument at a time. Do not
attempt to stockpile spare cells.
If a cell was working satisfactorily, but ceases to function before the
warranty period expires, the customer will receive credit toward the purchase of
a new cell.
If you have a warranty claim, you must return the cell in question to the
factory for evaluation. If it is determined that failure is due to faulty workmanship
or material, the cell will be replaced at no cost to the customer.
NOTE: Evidence of damage due to tampering or mishandling will render the
cell warranty null and void.
5-4
Teledyne Analytical Instruments
Percent Oxygen Analyzer Appendix
Appendix
A.1 Specifications
Ranges: 0-3 % and 0-10 % oxygen (Standard
Ranges), and 0-25 % (nominal) Calibration
Range. User selectable % Ranges can be set
between 1% and 25 % oxygen
Signal Output: Voltage: 0–10 V dc, negative ground
Current: 4-20 mA, negative ground
Range ID: 0-10 V dc.
Display: Light emitting diode display.
Alarms: Two customer selectable high or low fully
adjustable alarms. One cell failure alarm.
Alarm relays "C" contacts dry contacts rated
at 2A for 30VDC, 0.5A for 115VAC.
System Operating Temp: 0-50 °C
Accuracy: ±2% of full scale at constant temperature
±5% of full scale through operating temp.
range once temp. equilibrium is reached. (At
3 % and 5 % user defined ranges.)
Response Time: 90% in less than 20 seconds at 25 °C.
System Power Requirements: AC (100 to 240 V ac, 50/60 Hz).
System Enclosure: Rack mount with handles. Dimensions
(Approx.) 19 W x 5 H x 5 D.
Sensor Type: Micro Fuel Cell Class R-22..
Analysis Unit: 4.0" H × 6.0" W × 2.5" D
(101.6 mm × 152.4 mm × 63.5 mm)
Teledyne Analytical Instruments
A-1
Appendix Model 3290
A. 2 Spare Parts List
QTY. P/N DESCRIPTION
1 C-65220 PC Board, Main
1 C-64586A PC Board, Power Supply, AC Version
1 C64586B PC Board, Power Supply, DC Version
1 C-57283-E2 Micro-Fuel Cell, E-2
1 A33748 Thermistor Assembly
4 F-1128 Fuse (AC), ½A, 250 V ac
4 F-51 Fuse (DC), ½A, 125 V dc
1 A-64678A Probe to Analyzer Cable, 6 ft
A minimum charge is applicable to spare parts orders.
IMPORTANT: Orders for replacement parts should include the part number
and the model and serial number of the system for which the
parts are intended.
Send orders to:
TELEDYNE ELECTRONIC TECHNOLOGIES
Analytical Instruments
16830 Chestnut Street
City of Industry, CA 91749-1580
Telephone: (626) 934-1500
TWX: (910) 584-1887 TDYANYL COID
Fax: (626) 961-2538
Web: www.teledyne-ai.com
or your local representative.
A-2
Teledyne Analytical Instruments
Percent Oxygen Analyzer Appendix
A.3 Reference Drawing
C-64643 Final Assembly (and interconnection diagram)
C-64771 Outline Diagram
A.4 Miscellaneous
The symbol: ~ is used on the rear panel of the model 3290 to signify
volts alternating current (V ac).
Teledyne Analytical Instruments
A-3
Appendix Model 3290
Model 3290PA AL Options
Model 3290 AL option is used by AIR LIQUIDE, MEDAL,
INDECOR and others.
The special features include:
Analysis Unit and Cable Assembly
The standard oxygen analysis unit (AU) has been replaced with a
special AU (P/N B61178). The cable assembly (P/N A61177) supplied for
use with the AU is ten feet in overall length.
NOTE: The AU does not have a mounting plate or terminal strip. How-
ever, the manifold block of the AU contains two screw holes
tapped for 10-32 UNF-2B x .500" that are suitable for mounting
purposes. (See drawing C-64643 for a sample interconnection.)
NOTE: The micro-fuel cell used in this instrument is not orientation
dependent. However, to minimize the possibility of contamination
from particulates or moisture, TET/AI recommends that the cell
assembly be kept in an upright position as is shown in drawing
C-64643.
Out-Of-Range Indicator
An IC on the Power Supply PCB (C-64586) has been installed for the
out-of-range identification feature.
When the high analysis range is set, an output of ≈15VDC (45mA
maximum) is available at the rear panel "RANGE ID" terminal block. (This
output can be used to drive a relay or some other indicator.) When the low
analysis range is set, the output at the terminal block drops to ≈0VDC. (To
set the high or low ranges, see paragraph 4.3 in this manual.)
NOTE: When the instrument is in the "AUTO" mode, the output at the
"RANGE ID" terminal block will be as follows:
≈≈
HI
≈
15VDC
≈≈
≈≈
LO
≈
0VDC
≈≈
A-4
≈≈
CAL
≈
15VDC
≈≈
Teledyne Analytical Instruments
Percent Oxygen Analyzer Appendix
Drawing Changes
The following drawings should be used with Model 3290 AL:
C-65676 Final Assembly/Interconnection
C-66095 Outline Diagram, Model 3290 Oxygen Analyzer
B-61176 Outline Diagram, Probe Analysis Unit
Teledyne Analytical Instruments
A-5
Appendix Model 3290
A.5 Material Safety Data Sheet
Section I – Product Identification
Product Name: Micro-Fuel Cells
Mini-Micro-Fuel Cells, all classes
Super Cells, all classes except T–5F
Electrochemical Oxygen Sensors, all classes.
Manufacturer: Teledyne Analytical Instruments
Address: 16830 Chestnut Street, City of Industry, CA 91749
Phone: (626) 961-9221
Date Prepared or Last Revised: 08/08/91
Emergency Phone Number: (626 961-9221
Section II – Physical and Chemical Data
Chemical and Common Names: Potassium Hydroxide (KOH), 15% (w/v)
Lead (Pb), pure
CAS Number: KOH 1310–58–3
Pb 7439–92–1
KOH (15% w/v) Pb (pure)
Melting Point/Range: –10 to 0 °C 328 °C
Boiling Point/Range: 100 to 115 °C 1744 °C
Specific Gravity: 1.09 @ 20 °C 11.34
pH: >14 N/A
Solubility in Water: Completely soluble Insoluble
Percent Volatiles by Volume: None N/A
Appearance and Odor: Colorless, odorless solution Grey metal,
odorless
A-6
Teledyne Analytical Instruments
Percent Oxygen Analyzer Appendix
Section III – Physical Hazards
Potential for fire and explosion: The electrolyte in the Micro-Fuel Cells
is not flammable. There are no fire or explosion hazards associated with
Micro-Fuel Cells.
Potential for reactivity: The sensors are stable under normal conditions of
use. Avoid contact between the sensor electrolyte and strong acids.
Section IV – Health Hazard Data
Primary route of entry: Ingestion, eye/skin contact
Exposure limits:OSHA PEL: .05 mg/cu.m. (Pb)
ACGIH TLV: 2 mg/cu.m. (KOH)
Effects of overexposure
Ingestion: The electrolyte could be harmful or fatal
if swallowed.
Oral LD50 (RAT) = 3650 mg/kg
Eye: The electrolyte is corrosive; eye contact
could result in permanent loss of vision.
Dermal: The electrolyte is corrosive; skin contact
could result in a chemical burn.
Inhalation: Liquid inhalation is unlikely.
Signs/symptoms of exposure: Contact with skin or eyes will cause a
burning sensation and/or feel soapy or
slippery to touch.
Medical conditions
aggravated by exposure: None
Carcinogenicity: NTP Annual Report on Carcinogens: Not
listed
LARC Monographs: Not listed
OSHA: Not listed
Other health hazards: Lead is listed as a chemical known to the
State of California to cause birth defects
or other reproductive harm.
Teledyne Analytical Instruments
A-7
Appendix Model 3290
Section V – Emergency and First Aid Procedures
Eye Contact: Flush eyes with water for at least 15 minutes and get im-
mediate medical attention.
Skin Contact: Wash affected area with plenty of water and remove
contaminated clothing. If burning persists, seek medical
attention.
Ingestion: Give plenty of cold water. Do not induce vomiting.
Seek medical attention. Do not administer liquids to an
unconscious person.
Inhalation: Liquid inhalation is unlikely.
Section VI – Handling Information
NOTE: The oxygen sensors are sealed, and under normal circumstances,
the contents of the sensors do not present a health hazard. The
following information is given as a guide in the event that a cell
leaks.
Protective clothing: Rubber gloves, chemical splash goggles.
Clean-up procedures: Wipe down the area several times with a wet pa-
per towel. Use a fresh towel each time.
Protective measures
during cell replacement:Before opening the bag containing the sensor
cell, check the sensor cell for leakage. If the sensor cell leaks, do not open the bag. If there is
liquid around the cell while in the instrument,
put on gloves and eye protection before removing the cell.
Disposal: Should be in accordance with all applicable
state, local and federal regulations.
NOTE: The above information is derived from the MSDS provided by the
manufacturer. The information is believed to be correct but does
not purport to be all inclusive and shall be used only as a guide.
Teledyne Analytical Instruments shall not be held liable for any
damage resulting from handling or from contact with the above
product.
A-8
Teledyne Analytical Instruments
Loading...