2B Technologies 306 User manual

Model 306 Ozone Calibration Source Manual Rev. G-1
i
Ozone Calibration Source
2BTechnologies
OPERATION MANUAL
Model 306
© Copyright 2020, 2B Technologies
All rights reserved.
Technical Support:
https://twobtech.com/tech-support.html
[email protected]m
[phone]

Model 306 Ozone Calibration Source Manual Rev. G-1
ii
Contents
IDENTIFICATION RECORDS iv
PRINTING HISTORY v
WARRANTY STATEMENT vi
SAFETY WARNINGS vii
1. INTRODUCTION 1
1.1 Theory of Operation................................................................................................................. 1
1.2 Summary of Schematic Diagram............................................................................................. 3
2. SPECIFICATIONS: MODEL 306 OZONE CALIBRATION SOURCE 4
3. STARTUP OPERATION 5
3.1 Shipping Box Contents............................................................................................................ 5
3.2 Startup of the Ozone Calibration Source™............................................................................. 5
3.3 Model 306 Installation Guidelines ........................................................................................... 7
3.3.1 Typical Installation: Connection to a Device Drawing Flow from the Model 306 ............ 7
3.3.2 Alternative Installation: Pushing Flow from the Model 306.............................................. 7
3.3.3 Suggestions for Measuring the Flow to the User’s Equipment ....................................... 7
4. OPERATION VIA THE LCD MENU 9
4.1 Menu Overview........................................................................................................................ 9
4.2 Configuration Menu (Cfg)......................................................................................................10
4.2.1 Calibration Submenu..................................................................................................... 10
4.2.2 Program Submenu......................................................................................................... 11
4.2.3 Scheduler Submenu...................................................................................................... 12
4.2.4 Date/Time Submenu......................................................................................................12
4.3 Ozone Menu (O3)..................................................................................................................12
4.4 Start Step Menu (Stp)............................................................................................................13
4.5 Zero Menu (Zer) ....................................................................................................................13
5. USING THE SERIAL INTERFACE 14
5.1 Collecting Diagnostic Data over the Serial Port in Real Time via the LCD........................... 14
5.2 Operating the Instrument Remotely via the Serial Menu ......................................................15
5.3 Hibernate Feature.................................................................................................................. 16
6. USING THE VOLTAGE OUTPUT (Vout) 17
6.1 Using the Voltage Output to Measure Ozone Output Concentration.................................... 17
6.2 Using the Voltage Output for Error Diagnostics ....................................................................17
7. USING THE MODEL 306 TO CALIBRATE AN OZONE MONITOR 18
7.1 Flow Requirement ................................................................................................................. 18
7.2 Attaching the Ozone Cal Source™to an Ozone Monitor...................................................... 18
7.2.1 Overview........................................................................................................................18
7.2.2 Installation of the Model 306 on a Sampling Line.......................................................... 18
7.3 Running a Calibration of an Ozone Monitor.......................................................................... 19
8. CALIBRATING THE MODEL 306 OZONE CALIBRATION SOURCE 20

Model 306 Ozone Calibration Source Manual Rev. G-1
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9. MAINTENANCE/TROUBLESHOOTING 21
10. LABELED INSTRUMENT PHOTOS 23
11. PARTS LIST 27
12. SERVICE LOG 28

Model 306 Ozone Calibration Source Manual Rev. G-1
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IDENTIFICATION RECORDS
Record the following information for future reference:
Unit serial number:
Warranty start date:
(date of receipt)

Model 306 Ozone Calibration Source Manual Rev. G-1
v
PRINTING HISTORY
This manual covers the Model 306 Ozone Calibration Source™. The Model 306 is a
portable source of ozone that can be used to provide ozone in the range of 0 to 1000
parts per billion by volume (ppbv) for the calibration of ozone analyzers and other
applications where a precise and accurate supply of ozone is required. New editions
of this manual are complete revisions that reflect updates to the instrument itself, as
well as clarifications, additions and other modifications of the text.
Revision A .............................................................................................December 2006
Revision B ......................................................................................................April 2011
Revision C.............................................................................................November 2014
Revision D......................................................................................................June 2015
Revision E (serial no. 307 and above)...................................................November 2016
Revision E-2 (serial no. 307 and above).....................................................August 2017
[Clarifications on the scheduler feature, serial connection, 3-way valve, Vout, photo labels, and
Figure 1-1 schematic. Expanded information in the introduction, startup operation, specifications,
calibration sections, and instrument photos. Reorganized major Sections, and added the Parts
section. Corrected external battery requirements specified in Section 3.2 and midnight hour setting
in Section 4.2.3.]
Revision F-1 (serial no. 445; 447 and above)........................................December 2019
[New pictures (Figures 10-2 and 10-3) to reflect change to a different flowmeter. New Section 3.3
giving installation guidelines. Addition of links to 2B Tech’s published paper on the Model 306
(Section 1). Updated html links. Other minor updates and edits.]
Revision G-1 (serial no. 480 and above) ..............................................September 2020
[Increased flow specification to 4.0 L/min. Updated all photos to reflect small plumbing changes
made starting with serial no. 468 (replacement of Nylon tee with Kynar tee and Nylon bulkhead with
SS bulkhead) and other changes.]
TRADEMARKS & PATENTS
2B Technologies™, 2B Tech™, 2B, Ozone Calibration Source™, and Ozone Cal
Source™are trademarks of 2B Technologies.
CONFIDENTIALITY
The information contained in this manual may be confidential and proprietary and is the
property of 2B Technologies. Information disclosed herein shall not be used to
manufacture, construct, or otherwise reproduce the goods disclosed herein. The
information disclosed herein shall not be disclosed to others or made public in any
manner without the expressed written consent of 2B Technologies.
© Copyright 2020, 2B Technologies
All rights reserved.

Model 306 Ozone Calibration Source Manual Rev. G-1
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WARRANTY STATEMENT
2B Technologies warrants its products against defects in materials and workmanship.
2B Technologies will, at its option, repair or replace products which prove to be
defective. The warranty set forth is exclusive and no other warranty, whether written
or oral, is expressed or implied. 2B Technologies specifically disclaims the implied
warranties of merchantability and fitness for a particular purpose.
Warranty Periods
The warranty period is one (1) year from date of receipt by the purchaser, but in no
event more than thirteen (13) months from original invoice date from 2B Technologies.
Warranty Service
Warranty Service is provided to customers via web ticket, email, and phone support,
Monday - Friday, from 9:00 a.m. to 5:00 p.m., Mountain Time USA. The preferred
method of contacting us is through our web ticketing software at:
https://twobtech.com/tech-support.html
This way all technical staff at 2B Tech will be alerted of your problem and able to
respond. When you receive an email reply, please click on the Ticket link provided to
continue to communicate with us directly over the internet. The web ticket approach
to customer service allows us to better track your problem and be certain that you get
a timely response. We at 2B Tech pride ourselves on the excellent customer service
we provide.
You may also contact us by email at [email protected] or by phone at
[phone]. In either case, a web ticket will be created, and future
communications with you will be through though that ticket.
Initial support involves trouble-shooting and determination of parts to be shipped from
2B Technologies to the customer in order to return the product to operation within
stated specifications. If such support is not efficient and effective, the product may be
returned to 2B Technologies for repair or replacement. Prior to returning the product,
a Repair Authorization Number (RA) must be obtained from the 2B Technologies
Service Department. We will provide you with a simple Repair Authorization Form to
fill out to return with the instrument.
Shipping
2B Technologies will pay freight charges for replacement or repaired products shipped
to the customer site. Customers shall pay freight charges for all products returning to
2B Technologies.

Model 306 Ozone Calibration Source Manual Rev. G-1
vii
Conditions
The foregoing warranty shall not apply to defects resulting from improper or
inadequate maintenance, adjustment, calibration or operation by customer.
Maintenance, adjustment, calibration or operation must be performed in accordance
with instructions stated in the Ozone Calibration Source™manual. Usage of
maintenance materials purchased from suppliers other than 2B Technologies will void
this warranty.
Limitation of Remedies and Liability
The remedies provided herein are the Customer's sole and exclusive remedies. In no
event shall 2B Technologies be liable for direct, indirect, special, incidental or
consequential damages (including loss of profits) whether based on contract, tort or
any other legal theory. The Ozone Calibration Source™manual is believed to be
accurate at the time of publication and no responsibility is taken for any errors that
may be present. In no event shall 2B Technologies be liable for incidental or
consequential damages in connection with or arising from the use of the Ozone
Calibration Source™manual and its accompanying related materials. Warranty is
valid only for the country designated on the 2B Technologies quote or invoice.
SAFETY WARNINGS
The Model 306 Ozone Calibration Source is designed specifically to produce ozone.
Ozone is a toxic gas and should be handled with caution. The same kind of care
should be taken in handling the output of the Ozone Cal Source™as for any other
toxic gas that, for example, may come from a compressed gas cylinder. Under normal
operating conditions, the instrument will produce ozone in air at concentrations up to 1
to 2 ppm. The main danger is from inhalation of such high concentrations of ozone.
As a safety measure, a cap is provided for the ozone outlet. When the cap is properly
secured all of the ozonated air is diverted through an ozone scrubber inside the
instrument. When attached to an ozone monitor, the ozone may be exhausted to the
ambient environment by the ozone monitor, depending on the ozone monitor design.
Thus, when calibrating ozone monitors, one should know in advance how the ozone
exhaust is handled. It may be necessary to attach an ozone scrubber either prior to or
after the ozone monitor air pump. Alternatively, one can perform the calibration inside
a chemical hood. 2B Technologies provides inexpensive, high conductance ozone
scrubbers that can be used to scrub the exhaust of ozone monitors.

Model 306 Ozone Calibration Source Manual Rev. G-1
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ENGLISH
WARNING:
Any operation requiring access to the inside of the equipment, could result
in injury. To avoid potentially dangerous shock, disconnect from power
supply before opening the equipment.
WARNING:
This symbol, on the instrument indicates that the user should refer to
the manual for operating instructions.
WARNING:
If this instrument is used in a manner not specified by 2B Technologies,
USA, the protection provided by the instrument may be impaired.
ESPAÑOL
ATENCION:
Cualquier operación que requiera acceso al interior del equipo, puede
causar una lesión. Para evitar peligros potenciales, desconectarlo de la
alimentación a red antes de abrir el equipo.
ATENCION:
Este símbolo, en el instrumento indica que el usuario debería
referirse al manual para instrucciones de funcionamiento.
ATENCION:
Si este instrumento se usa de una forma no especificada por 2B
Technologies, USA, puede desactivarse la protección suministrada por el
instrumento.
FRANÇAIS
ATTENTION:
Chaque opération à l’intérieur de l’appareil, peut causer du préjudice. Afin
d’éviter un shock qui pourrait être dangereux, disconnectez l’appareil du
réseau avant de l’ouvrir.
ATTENTION:
Le symbol, indique que l’utilisateur doit consulter le manuel
d’instructions.
ATTENTION:
Si l’instrument n’est pas utilisé suivant les instructions de 2B Technologies,
USA, les dispositions de sécurité de l’appareil ne sont plus valables.
DEUTSCH
WARNHINWEIS:
Vor dem Öffnen des Gerätes Netzstecker ziehen!
WARNHINWEIS:
Dieses, auf dem Gerät weist darauf hin, dab der Anwender zuerst
das entsprechende Kapitel in der Bedienungsanleitung lesen sollte.
WARNHINWEIS:
Wenn das Gerät nicht wie durch die Firma 2B Technologies, USA,
vorgeschrieben und im Handbuch beschrieben betrieben wird, können
die im Gerät eingebauten Schutzvorrichtungen beeinträchtigt werden.
ITALIANO
ATTENZIONE:
Qualsiasi intervento debba essere effettuato sullo strumento può essere
potenzialmente pericoloso a causa della corrente elettrica.
Il cavo di alimentazione deve essere staccato dallo strumento prima della
sua apertura.
ATTENZIONE:
Il simbolo, sullo strumento avverte l’utilizzatore di consultare il
Manuale di Istruzioni alla sezione specifica.
ATTENZIONE:
Se questo strumento viene utilizzato in maniera non conforme alle
specifiche di 2B Technologies, USA, le protezioni di cui esso è dotato
potrebbero essere alterate.
DUTCH
OPGELET:
Iedere handeling binnenin het toestel kan beschadiging veroorzaken.
Om iedere mogelijk gevaarlijke shock te vermijden moet de aansluiting
met het net verbroken worden, vóór het openen van het toestel.
OPGELET:
Het symbool, geeft aan dat de gebruiker de instructies in de
handleiding moet raadplegen.
OPGELET:
Indien het toestel niet gebruikt wordt volgens de richtlijnen van 2B
Technologies, USA gelden de veiligheidsvoorzieningen niet meer.
CHINESE
警告：
任何需要接触设备内部的操作均可能造成人身伤害。为避免可能
的触电危险，请在打开设备前切断电源。
警告：
这个符号 在仪器上表示用户应参考说明书上的操作指南。
警告 :
如果仪器没有按照美国2B科技公司指定方式操作，仪器的保护性
能会减弱。
JAPANESE
警告：
機器の内部で操作する時、怪我できます。危険な衝撃を回避
するために、機器を開ける前に、電源を切断してください。
警告：
機器でこの記号 を見れば、マニュアルを読んでください。
警告：
この機器は2B テクノロジー会社、
USAの指定でしなければ、機器の保護が損なえます。

Model 306 Ozone Calibration Source Manual Rev. G-1
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1. INTRODUCTION
The Model 306 Ozone Calibration Source™(OCS™) is a portable source of ozone
that allows one to calibrate any ozone monitor, or to supply a calibrated source of
ozone for experiments such as exposure studies. It has been described in a peer-
reviewed publication in the journal Atmospheric Measurement Techniques (11, 4797-
4807, 2018; https://twobtech.com/2018_AMT_O3_Calibration_Source.pdf). Major
features of the Model 306 are:
•The instrument scrubs ozone from ambient air and produces either zero air or air
having a mixing ratio of ozone in the range 30-1,000 parts-per-billion by volume
(ppbv). The desired ozone concentration is chosen from the easy-to-use LCD
menu using a rotary select switch, or from a serial connection.
•The instrument can be programmed to output up to 10 individual ozone step
concentrations over a chosen time interval, for uses such ascalibrating ozone monitors.
•The instrument has a scheduler feature for once-daily automated execution of the
step program, at the user-specified hour.
•The total output volumetric flow rate is 4.0 L/min.
•The ozone mixing ratio is controlled so as to be independent of ambient
temperature, pressure, and humidity.
•A three-way valve in the Model 306 OCS™allows the user to switch their ozone
monitor easily from air sampling mode to calibration mode.
The Ozone Cal Source™output may be connected directly to the inlet of any ozone
monitor (provided that the ozone monitor’s sampling rate is less than 4.0 L/min); the
excess flow is vented through an ozone scrubber internal to the OCS™. Besides
portability, an important advantage of the Model 306 OCS™is that it provides a
known concentration of ozone in ambient air containing the same level of humidity as
the air sample to be measured.
The Ozone Cal Source™is factory calibrated against a NIST-traceable ozone
standard. However, the calibration parameters may be changed in the menu in case
the user wants to recalibrate the OCS™against a separately maintained standard;
i.e., the Ozone Cal Source™can be used as a transfer standard. The OCS™may be
used, for example, for maintaining the calibration of a large number of ozone monitors
in the field relative to a highly stable laboratory instrument. In this case, a huge
advantage of the OCS™is its portability.
Besides its use as a calibrator of ozone monitors, the Ozone Cal Source™may be
used as a calibrated ozone source for studies of the effects of ozone on materials
(rubber, plastics, paints, etc.) and on biological organisms such as plants.
1.1 Theory of Operation
The portable Ozone Calibration Source makes use of a low-pressure mercury lamp to
photolyze oxygen and produce ozone. The vacuum UV lines near 185 nm are

Model 306 Ozone Calibration Source Manual Rev. G-1
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absorbed by O2 to produce oxygen atoms. The oxygen atoms attach to O2to form
ozone, O3. The well-known mechanism, which is responsible for the presence of
Earth’s protective ozone layer, is as follows:
O2+ h→O + O (1)
2 [O + O2+ M →O3+ M] (2)
____________________
Net: 3 O2+ h→2 O3(3)
where hsymbolizes a photon of light and M is any molecule (e.g., N2, O2, Ar).
Absorption of one photon of light by O2results in the formation of two ozone
molecules. The concentration of ozone produced in a flowing stream of air depends
on the intensity of the photolysis lamp, the concentration of oxygen (determined by
pressure and temperature), and the residence time in the photolysis cell (determined
by volumetric flow rate and cell volume). By holding these parameters constant, it is
possible to produce a flow of air containing a constant concentration of ozone, and the
concentration of ozone produced can be varied most conveniently by varying the lamp
intensity. Figure 1-1 is a schematic diagram of the Ozone Calibration Source™.
Figure 1-1. Schematic diagram of the Model 306 Ozone Calibration Source™.
Photolysis Chamber
UV Lamp
Ozone/Zero Calibration Air
from Model 306
Mass Flow Meter
Air Pump
Ozone & NOxScrubber
Air In
Photodiode
2BTechnologies Model 306
Ozone Calibration Source™
Ambient
Sample Air
To User’s Ozone Monitor or
System: Ozone/Zero Calibration
Air or Ambient Sample Air
3-Way Valve
Overflow/
O3Scrubber

Model 306 Ozone Calibration Source Manual Rev. G-1
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1.2 Summary of Schematic Diagram
An air pump pushes air through a particle filter, then through a mass flow meter. The
microprocessor controls the flow rate at a value of 4.0 L/min volumetric by means of
pulse-width modulation of the power to the pump. Before entering the photolysis
chamber, the air passes through an ozone/NOxscrubber to remove any ambient
ozone and NOx. The air passes through another particle filter, and then passes
through the photolysis chamber containing a low-pressure mercury lamp where
absorption of atomic lines near 185 nm produces oxygen atoms from molecular
oxygen, and the oxygen atoms react with molecular oxygen to form ozone (reactions
1, 2, and 3 above). The lamp intensity is monitored by a photodiode and controlled by
the microprocessor. The photodiode voltage is calibrated against the output ozone
concentration. Pressure within the gas stream is measured but not controlled.
Instead, the lamp intensity is varied to compensate for changes in pressure using a
proprietary algorithm. Air containing ozone exits the photolysis cell through an
overflow tee, where excess air not sampled by the ozone monitor being calibrated is
exhausted through an internal ozone scrubber. If it is desired to have the full 4.0
L/min of air/ozone exit the instrument, the internal ozone scrubber may be capped.
The other end of the overflow tee goes to a valve which selects either the ambient
sample air or the calibration air to exit through the output of the 306.
Further information about 2B Tech’s Model 306 Ozone Calibration Source may be
found in the journal article published in Atmospheric Measurement Techniques:
Portable ozone calibration source independent of changes in temperature, pressure
and humidity for research and regulatory applications, J.W. Birks, C.J. Williford,
P.C. Andersen, A.A. Turnipseed, S. Strunk, and C.A. Ennis, Atmospheric
Measurement Techniques, 11, 4797-4807, 2018.
The paper is accessible through the link here:
https://twobtech.com/2018_AMT_O3_Calibration_Source.pdf

Model 306 Ozone Calibration Source Manual Rev. G-1
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2. SPECIFICATIONS: MODEL 306 OZONE CALIBRATION SOURCE
Method of Ozone Production
UV photolysis of molecular oxygen (O2) at 185 nm
Ozone Concentration Range
0 ppbv and 30 ppbv to 1,000 ppbv *
Output Flow Rate
4.0 L/min volumetric
Precision and Accuracy
Greater of 2.0 ppbv or 2.0% of ozone concentration
Response Time for Change in
Ozone Output Concentration
< 30 s to reach 95% of selected concentration
Dimensions
3.5 × 6.3 × 11.6 inches (9 × 21 × 29 cm)
Weight
5.6 lb (2.6 kg)
Power Requirements
12 V DC or 120/240 V AC, 18 watt
Analog Output
Yes; voltage output tracks ozone output and provides
system error codes
Serial Connection
Yes; for remote operation and for system diagnostics
Programmable Output
Yes, user-specified ozone output for up to 10 steps from
0 to 1,000 ppbv; stored in internal memory
Scheduler
Yes; once-daily execution of the step program at user-
specified hour
Baud Rate
4800
*Even though the instrument is capable of producing greater than 1,000 ppbv of ozone, the
upper limit to the concentration that can be accurately controlled should be assumed to be
1,000 ppbv.

Model 306 Ozone Calibration Source Manual Rev. G-1
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3. STARTUP OPERATION
Please read all the following information before attempting to install the Ozone
Calibration Source™. For assistance, please call 2B Technologies at [phone]
or email us at [email protected].
NOTE:
Save the shipping carton and packing materials that came with the Ozone
Calibration Source™. If the Ozone Calibration Source™must be returned to the
factory, pack it in the original carton. Any repairs as a result of damage
incurred during shipping will be charged.
3.1 Shipping Box Contents
Open the shipping box and verify that it contains all of the items on the shipping list. If
anything is missing or obviously damaged, contact 2B Technologies immediately.
3.2 Startup of the Ozone Calibration Source™
To operate the Ozone Calibration Source™, connect it to an external power source
and turn the instrument on by flipping the front panel switch. The instrument requires
a 12 V DC source which can be supplied by: 1) the 110-220 V AC power adapter (2.5
amp or higher), 2) a cigarette lighter adapter plugged into a 12 V DC source such as
found in an automobile or many light aircraft, or 3) a 12 V battery. The source must
be very close to 12 V because of the power requirements of the instrument’s pump.
When using a battery, be certain to attach the positive (red) and negative (black) wires
correctly. A circuit breaker and diode are installed on the circuit board in case of an
electrical short or incorrect battery attachment. If activated, the breaker will reset itself
after a few minutes.
Once turned on, the instrument will briefly display the version number of the software
installed on the microprocessor. The instrument will then display
Warming up …
delT = -xx.xx
where delT is the deviation of the temperature of the photolysis chamber from the set
point of 315 K (42°C). As the chamber warms up, the temperature deviation will be
continuously displayed. During the warmup period, the photolysis lamp and the pump
are turned off and the internal 3-way valve is set to divert sample air to the output of
the Model 306.
Warmup will take approximately 15-20 minutes. Once delT is within 1°C of the set
point, the display will read: Temperature Set
Press Select

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Press in and hold the black Select switch on the front of the instrument to bring up the
LCD Menu. See the next section for a description of how to operate the instrument
using this menu.
The user’s ozone monitor, or other experimental system, can be attached to the Model
306 OCSTM to receive air containing calibrated amounts of ozone. Alternatively, a 3-
way valve inside the Model 306 OCSTM can be set so that air from a sampling inlet on
the back of the instrument bypasses the Model 306 and is routed to the user’s ozone
monitor or system. When the Model 306 OCSTM is turned off, or in hibernation mode
(discussed in Section 5.3), the valve is set so that air is routed from the sampling inlet.
This permits the user to leave the Model 306 OCSTM plumbed in-line with their ozone
monitor or other system when the Model 306 is not in use.
Model 306 Output:
O3Calibration Air
or
Sample Air from Inlet
Sample Air
Inlet
Select Switch

Model 306 Ozone Calibration Source Manual Rev. G-1
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3.3 Model 306 Installation Guidelines
3.3.1 Typical Installation: Connection to a Device Drawing Flow from the Model
306
The Model 306 is often used to calibrate an ozone monitor or to provide a known
ozone concentration to another kind of equipment that draws flow from the calibrator.
The Model 306 is designed for this type of installation. Inside the Model 306, an air
pump maintains a total flow of ~ 4 L/min through the ozone generator. Any portion of
the total flow that is not being drawn into the user’s equipment is vented through an
internal ozone scrubber and vented inside the enclosure (Figure 3-1).
Figure 3-1. Schematic of the Model 306 showing the internal overflow scrubber and vent for
any unused portion of the total flow rate.
3.3.2 Alternative Installation: Pushing Flow from the Model 306.
For some applications, it may be desirable to configure the Model 306 to push into a
chamber or other type of passive equipment that does not actively pull or push flow.
In the case that the equipment is not very restrictive and is near ambient pressure, the
Model 306 may provide enough flow (up to ~ 1 L/min) and will not need any additional
modification. If more flow is needed (up to ~ 4 L/min) or the chamber/equipment is
fairly flow-restrictive, a needle valve can be installed on the outlet of the internal
overflow scrubber (see Figure 3-2, next page). Adjustment of the needle valve will
control the portion of flow that is vented inside the box and the portion that is directed
to the outlet.
3.3.3 Suggestions for Measuring the Flow to the User’s Equipment
If the user wants to measure the flow rate delivered to their equipment, we suggest
they use one of the following methods:
1. Use a flow meter on the internal overflow scrubber to measure the vented flow
rate and read the total flow rate from the Model 306. The flow to the user’s
equipment is the difference between these two measurements.
2. Use a scrubber after the user’s equipment and then a flow meter. This allows
for direct measurement of the process flow, but may pressurize the process if
the scrubber or flow meter is restrictive. Ozone must be destroyed in the gas
stream using a scrubber to prevent damage to the user’s flow meter.
Model 306 Ozone Calibration Source
Internal
Overflow
Scrubber
Vent
Ozone
Generator
Air
Pump
User’s
Equipment

Model 306 Ozone Calibration Source Manual Rev. G-1
8
Figure 3-2. Photograph of the Model 306 showing where a needle valve can be installed to
increase the flow or pressure at the outlet.
Ozone Generator
Place to install a needle
valve for increasing the
outlet flow or pressure
Outlet
Internal
Overflow
Scrubber

Model 306 Ozone Calibration Source Manual Rev. G-1
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4. OPERATION VIA THE LCD MENU
4.1 Menu Overview
Any time after powering the instrument on, you may enter the main menu by holding in
the rotary select switch until the menu appears. Once the menu appears, release the
select switch. (Note: You may enter the menu without waiting for the warm up to be
complete; however, the ozone concentration selected will not be accurately output
until the set point temperature is reached.)
The following diagram summarizes the complete LCD menu.
Menu
Cfg O3 Cfg Zer
Prg
Cal
Stp
Vout O3_L
Sch D/T
O3_H
Figure 4-1. The LCD Menu of the Model 306 Ozone Calibration Source™.
After pressing the select switch the main menu will then be displayed as:
Menu
Cfg O3 Stp Zer
Rotating the select switch will move the blinking cursor to highlight the first character
of each of the four submenus, Cfg, O3, Stp and Zer. One can enter any one of these
submenus by rotating the select switch to move the cursor over the first letter of the
submenu, and then momentarily pressing (“clicking”) the select switch.

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4.2 Configuration Menu (Cfg)
Selecting the Cfg submenu will produce the following display:
Cfg Menu
Cal Prg Sch D/T 
where Cal is a submenu for entering the calibration menu; Prg is a submenu for
defining a programmed series of step ozone concentrations; Sch is a submenu that
allows the user to set the Model 306 to run an ozone step function once per day at a
chosen time; and D/T is a submenu for setting the date and time. The purpose of the
return symbol () is to return to the previous menu; i.e., depressing the select switch
when is highlighted allows one to move one level up in the menu. The function of
each submenu is described below.
4.2.1 Calibration Submenu
Choosing the Cal submenu results in the following submenu:
Cal Menu
Vout O3_L O3_H 
where Vout is a submenu for setting the voltage offset value and O3_L and O3_H are
submenus for setting the calibration factors for Ozone output.
Choosing Vout results in the following submenu:
Vout Offset Menu
Offset= xx mV 
There is an inherent electronic offset in the analog output of the ozone level being
produced. The Vout offset can be adjusted so that zero ozone will provide a
measurable positive voltage. It is adjustable from -99 millivolts to 99 millivolts, and this
setting is used to adjust the voltage output downward to 0.05 V for zero ozone output.
Vout itself can be used measure ozone concentrations, as well as to provide error
messages for diagnostic uses. More details are provided below in Section 6, “Using
the Voltage Output.”
In order to account for the small curvature in the plot of ozone concentration versus
lamp intensity, calibration parameters are entered into the instrument in two
concentration ranges: low (300 ppbv and below) and high (301-1000 ppbv). Choosing
O3_L results in the following submenu for setting the zero offset and slope for ozone
output in the ranges of 0 and 30-300 ppb, for example:
O3L Cal Menu
Z= 2 S= 1.05 
Choosing O3_H results in the following submenu for setting the slope and offset for
ozone output in the range of 301-1000 ppbv, for example:
O3H Cal Menu
Z= 1 S= 1.03 

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Both of the offset values, Z_L and Z_H, are in units of ppb. The Ozone Cal Source
is shipped with a NIST-traceable calibration. The calibration factors, Z_L, S_L,Z_H,
and S_H are set in the instrument and recorded in the instrument’s calibration
document and birth certificate. However, you may choose to change the calibration
factors so that the instrument output agrees with your own ozone standard. You can
always return the instrument to its factory calibration if desired. To change the
calibration factor, place the cursor over the Z_L, S_L,Z_H,or S_H and hold in the
select switch until the cursor blinks. You may now change the value of the calibration
factors by rotating the select switch. Increasing the slope (S_L) calibration factor
increases the ozone output concentration linearly for ozone values equal or less than
300 ppbv; i.e., for S=1.10, the ozone concentration produced will be 10% higher than
for S=1.00, and for S=0.95 it will be 5% lower. Likewise increasing the slope (S_H)
calibration factor increases the ozone output concentration linearly for ozone values
above 300ppbv. Once the desired value of S_L or S_H is selected, momentarily
press the select switch such that the cursor no longer blinks. The low and high offsets,
Z_L and Z_H, are set in a similar fashion (in units of ppb). You may now exit the Cal
submenu by selecting and clicking on .See Section 8 for information on calibrating
your Model 306 Ozone Cal SourceTM.
4.2.2 Program Submenu
Choosing the Prg submenu from the Cfg menu, allows one to define a program of
steps in ozone concentration. Choosing Prg results in the following submenu:
Prg Menu
Num Steps= x 
Upon placing the cursor under the currently set value x and clicking, a blinking cursor
will appear. You may now rotate the select switch to obtain the number of steps, up to
10, you wish to have in your program. Clicking again will turn off the blinking cursor
and you may return the cursor to to continue defining the program. After choosing
the number of steps, the following submenu will appear:
Prg Menu
Time/Step= x 
You may now move the cursor to the currently set time/step value x, click to obtain a
blinking cursor and rotate the select switch to choose a step time in the range 1 to 60
minutes. To select the value, click to remove the blinking cursor, then use to begin
defining the target concentrations of each of the steps. The following submenu will
now appear: Select O3 Step
Step[1]= xxxx 
where xxxx is the target ozone concentration in ppbv that is currently being used for
the first step of the program. You may now change the ozone concentration for the
first concentration step in the same way that the Time/step was changed. Executing
will bring up the following submenu and allow you to set the target concentration for
the next step: Select O3 Step
Step[2]= xxxx 

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This process is repeated until the target concentrations are set for all of the steps in
your program. These steps may span the full range of the instrument, from 0 to 1000
ppbv, if desired.
This program resides in memory until the next time you choose to change it.
4.2.3 Scheduler Submenu
Choosing the Sch submenu from the Cfg menu, allows one to schedule a once-daily
execution of the step program defined in Section 4.2.2. This could be used, for
example, to carry out a daily autocalibration of an ozone monitor. Choosing Sch
results in the following submenu: Sch Menu
Auto Cal Hr = x 
where x is the time (hour) to commence the step program, in military units (24 =
midnight). To turn off the scheduler function, use the select switch to scroll to “OFF.”
Important: After setting the scheduler hour, the user needs to power cycle the Model
306 off and back on, and leave it in the warm-up menu (it reads “temp set press
select”when the photolysis chamber is at temperature). If not left in this state, the
scheduled step program will not run.
4.2.4 Date/Time Submenu
From the Cfg menu, select the D/T submenu. The display will read, for example:
D/T: 14:32:21 
17/10/2016
meaning that it is 21 seconds after 2:32 p.m. on October 17, 2016 (military time and
European date). To change a number in the date and time, rotate the Select switch to
underline the numeral you want to change. A single click then causes a blinking
cursor to cover that numeral. The number can then be changed by rotating the Select
switch. Once the number is correct, click on the Select switch to turn off the blinking
cursor. You may now rotate the Select switch to choose another numeral to change.
Once the time and date is correct, clicking on will set the internal clock to that time
and return the display to the Cfg menu. As in setting a digital watch, the seconds
should be set in advance of the real time since the clock starts to run again only when
the set time is entered; in this case by clicking on .
4.3 Ozone Menu (O3)
You may choose to output a constant ozone concentration by choosing O3 from the
main menu. Upon clicking on O3, the following submenu will appear:
Select Amount
O3= xxxx 
You may change the desired target ozone concentration by selecting xxxx and
rotating the select switch to choose a value. To start producing that concentration of
ozone, click on .The instrument will now output the selected concentration of