Alpha Omega Instruments 3520 Operating Manual

SERIES 3520

TRACE OXYGEN ANALYZER

(Product shown with optional flow meter and pressure regulator)

Alpha Omega Instruments Corp.
40 Albion Road, Suite 100
Lincoln, RI 02865
Phone: [phone]
Fax: [phone]
Website: www.aoi-corp.com
Email: [e-mail]

VERSION 2.0 COPYRIGHT 06/16
ALPHA OMEGA INSTRUMENTS CORP. ALL RIGHTS
RESERVED INCLUDING THE RIGHT TO REPRODUCE
THIS MANUAL, OR ANY PORTION THEREOF, IN ANY FORM.

ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

WARRANTY

Alpha Omega Instruments Corp. warrants the products delivered to be free from defects in material
and workmanship at the time of delivery to the FOB point specified in the purchase order, its liability
under this warranty being limited to repairing or replacing, at Alpha Omega Instruments option, items
(excluding the oxygen sensor) which are returned to it prepaid within two (2) years from the date of
shipment and found to Seller’s satisfaction to be defective.

Alpha Omega Instruments one (1) year sensor warranty offers protection for one full year from the
date of shipment of the Series 3520 Portable Oxygen Analyzer. Any sensor from a Series 3520
Portable Oxygen Analyzer that fails under normal use must be returned to Seller prepaid and, if such
sensor is determined by Seller to be defective, Seller shall provide Buyer a replacement sensor. Buyer
must provide the serial number of the analyzer from which the sensor has been removed. If a sensor
is found to be defective and a new one issued, the warranty of the replacement sensor (s) is for a
period of one year from the date of shipment. At times, it may be necessary to ship a replacement
sensor in advance of receiving one returned for warranty claim. In such cases, if the returned sensor is
not covered under warranty, the user will be charged the full price of a replacement sensor. In no
event shall Alpha Omega Instruments Corp. be liable for consequential damages. NO PRODUCT IS

WARRANTED AS BEING FIT FOR A PARTICULAR PURPOSE AND THERE IS NO WARRANTY OF
MERCHANTABILITY.

This warranty applies only if:

(i) the items are used solely under the operating conditions and manner

recommended in this manual, specifications, or other literature;

(ii) the items have not been misused or abused in any manner or repairs attempted

thereon;

(iii) written notice of the failure within the warranty period is forwarded to Alpha

Omega Instruments Corp. and, the directions received for properly identifying
items returned under warranty are followed;

(iv) the return notice authorizes Alpha Omega Instruments Corp. to examine and

disassemble returned products to the extent the Company deems necessary to
ascertain the cause of failure.

The warranties stated herein are exclusive. THERE ARE NO OTHER WARRANTIES, EITHER
EXPRESSED OR IMPLIED, BEYOND THOSE SET FORTH HEREIN, and Alpha Omega Instruments
Corp. does not assume any other obligation or liability in connection with the sale or use of said
products.

Disclaimer of Warranty
Alpha Omega Instruments Corp. makes no representation or warranties, either expressed or implied, by or with
respect to anything in this manual, including, but not limited to, implied warranties of merchantability or fitness for
a particular purpose. In no event will Alpha Omega Instruments Corp. be liable for any damages, whether direct or
indirect, special, consequential, or incidental arising from the use of this manual. Some states in the USA do not
allow the exclusion of incidental or consequential damages. Alpha Omega Instruments Corp. also reserves the
right to make any changes to improve the performance of its products at any time and without notice.

ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

TABLE OF CONTENTS

PAGE

WARRANTY

SECTION 1.0 SPECIFICATIONS 1

SECTION 2.0 SYSTEM DESCRIPTION 3

SECTION 3.0 INSTALLATION PROCEDURES 4

SECTION 4.0 OPERATING PROCEDURES 6

SECTION 5.0 CALIBRATION PROCEDURES 7

SECTION 6.0 REPLACEMENT OF OXYGEN SENSOR 9

FIGURE 1.0 SERIES 3520 CONFIGURATION DRAWING 11

NOTE OF CAUTION 12

APPENDIX A MSDS FOR THE 3SEN OXYGEN SENSOR 13

ADDENDUM 1 OPTIONAL BLOCK & BLEED 16

ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

SECTION 1.0

SPECIFICATIONS

PERFORMANCE
Measurement Ranges (parts per million)

0-50, 0-100, 0-500, 0-1,000, 0-5,000, 0-10,000, and 0-20,000

Accuracy1: + 1% of full scale.

Linearity: + 1% of full scale.

Response Time: 90% of full scale response in less than 10 seconds (typical). The

response time for ranges of 0-50 PPM or less depend to a great
extent on the design of the sample delivery system including the
materials used.

Sensor Type: Long-life Ambient Temperature Electrochemical Sensor (Optional

CO2 Resistant Sensor Available).

Temperature Compensation: Standard.

Operating Temperature Range: 40° to 104° F (5° to 40° C)

<40° F (5° C) use heated sensor enclosure
>104° F (40° C) cooling of sample gas/sensor required

Warranty: Two years electronics one year sensor.

ELECTRICAL
Display: 3-1/2 digit liquid crystal display (4-1/2 digit for the 0-5,000,

0-10,000, and 0-20,000 ppm range instruments.

Input Power: Powered from eight AA Rechargeable NICAD batteries with built-

in universal AC battery charger.

Analog Output: No analog output.

SAMPLE GAS CHARACTERISTICS
Sample Flow Rate: 1.0 to 2.0 standard cubic feet per hour (SCFH).

0.5 to 1.0 liters/ minute (LPM).

Sample Gas Temperature: 40° to 104° F (5° to 40° C)

Sample Gas Pressure Limits: 0.1 to 1.5 psig (0.007 to 0.1 kg/cm2).

Entrained Solids: <3 mg/ft³: no in-line filter required

>3 mg/ft³: in-line filter is required

1 Stated at constant temperature and pressure.

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ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

Hydrocarbon Mist: <0.7 mg/ft³: no in-line filter required

>0.7 mg/ft³: in-line filter is required

CONSTRUCTION
Enclosure: Polycarbonate rated NEMA 1.

Dimensions: 6.5 inches (165.1 mm) height

6.5 inches (165.1 mm) width

7.8 inches (196.9 mm) height
Note: All dimensions are without optional equipment

Gas Connections: 1/4" stainless steel compression fittings.

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ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

SECTION 2.0

SYSTEM DESCRIPTION

General Description

The Series 3520 Portable Oxygen Analyzer is a portable trace oxygen analyzer designed to provide
accurate and dependable trace oxygen measurements in a variety of gases. The analyzer enclosure
is made from durable polycarbonate and is rated NEMA 1 for general purpose service. The instrument
is powered from eight AA NICAD batteries that are mounted internal to the analyzer. Recharging of
the batteries is done with a 115 VAC/60 Hz adapter that is shipped with the instrument. Options
include a pressure regulator, flowmeter, in-line filter, and pump.

Advanced Sensor Technology

The Series 3520 Portable Oxygen Analyzer features an advanced trace oxygen sensor. The sensor is
a lead-oxygen battery comprised of a lead anode, a gold plated cathode, and an electrolyte consisting
of potassium hydroxide. All types of electrochemical transducers have three primary components; a
cathode, anode, and electrolyte. In the Alpha Omega Instruments advanced sensor, the cathode is the
sensing electrode or the site where chemical reduction of the oxygen takes place.

The chemical reactions are as follows:

Cathode Reaction 4e- + O2 + 2H2O 4OH- (1)

In the above reaction, four electrons combine with one oxygen molecule to produce four hydroxyl ions.
This cathodic half-reaction occurs simultaneously with the following anodic half-reaction:

Anode Reaction Pb + 2OH- PbO + H2O + 2e (2)

The anode (lead) is oxidized (in a basic media) to lead oxide and in the process, two electrons are
transferred for each atom of lead that is oxidized. The sum of the half-reactions (1) and (2) results in
the overall reaction (3):

Overall Reaction O2 + 2Pb 2PbO (3)

From this reaction it can be seen that the sensor is very specific for oxygen providing there are no
gaseous components in the sample stream capable of oxidizing lead. The only likely compounds that
meet this requirement are the halogens (iodine, bromine, chlorine, and fluorine).

In reaction (1), four electrons are transferred for each oxygen molecule undergoing reaction. In order
to be reacted, and oxygen molecule must diffuse through both the sensing membrane and the thin film
of electrolyte maintained between the sensing membrane and the upper surface of the cathode. The
rate at which oxygen molecules reach the surface of the cathode determines the electrical output.
This rate is directly proportional to the concentration of oxygen in the gaseous mixture surrounding the
sensor cell.

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ALPHA OMEGA INSTRUMENTS CORP.
SERIES 3520 PORTABLE TRACE OXYGEN ANALYZER INSTRUCTION MANUAL

SECTION 3.0

INSTALLATION PROCEDURES

Unpacking the Instrument

Upon opening the shipping container, carefully unpack the analyzer to check if the outer surfaces have
been damaged. If so, report the findings immediately to Alpha Omega Instruments who will provide
further instructions. If there is no apparent damage, check the contents
to ensure all items were shipped. In some cases, items may be backordered.

All damage and shortage claims must be made
known to Alpha Omega Instruments within 10 days
after receipt of shipment.

Powering the Series 3520 Portable Oxygen Analyzer

The Series 3520 Portable Oxygen Analyzer is powered from eight AA NICAD batteries that are
mounted internal to the instrument. Recharging of the batteries is done with a 115 VAC/60 Hz adapter
that is shipped with the analyzer. To power up the instrument, place the front panel on/off switch to the
“ON” position. When the Series 3520 Portable Oxygen Analyzer is attached to the AC/DC adapter, the
NICAD batteries are being charged at the same time. If the batteries are allowed to run below the level
where normal operation can be sustained, the charge time will be approximately 16 hours. In the
event the batteries need to be replaced, use only NICAD batteries (Panasonic Type P-60AAR or
equivalent). Use of any other type of battery may damage the instrument and void the warranty.

Recharging the NICAD Batteries

The Series 3520 will provide in excess of 48 hours (without the optional pump) of continued operation
before battery recharging is required. If the pump is in use, up to 12 hours of continued use can be
achieved. To recharge the NICAD batteries, connect the 3.5 mm plug from the 12 VDC wall mounted
AC/DC adapter to the jack located on the rear of the instrument (see Figure 1.0). Allow 16 hours to
fully recharge the batteries. Though the analyzer can be used while recharging, if the optional pump is
in use during this time recharging will take an additional 5-10% longer.

Replacing the NICAD Batteries

The internal NICAD batteries are located in two banks of 4 size AA NICAD battery trays accessible on
the top of the instrument. If battery replacement becomes necessary the following steps should be
followed:

Use only Panasonic Type P-60AAR or
equivalent NICAD batteries with the Series
3520 Portable Oxygen Analyzer

To remove a battery pack tray, push the tabs (located at each end of the tray) towards each other to
release the latches and pull the trays out from the enclosure.

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