ion science TVOC User manual

Part number: 849215
Unrivalled Detection. www.ionscience.com
TVOC
Instrument User Manual V4.5

Part number: 849215
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TVOC MANUAL Ion Science Ltd
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Declaration of conformity
Manufacturer: Ion Science Ltd, The Way, Fowlmere, Cambridge, SG8 7UJ, UK
Product: TVOC
Product Description: An intrinsically safe fixed continuous monitor comprising of a photo-ionisation
detector for detecting and measuring volatile organic compounds with a 4-20mA
output
Directive 94/9/EC ATEX
Identification: II 2G EEx ia IIC T4 (-20oC ≤Ta ≤+50oC)
Notified Body: Baseefa Ltd, 1180, Buxton, UK
Identification: II 3G Ex nA IIC T4 (-40oC < Ta < +50oC)
Ion Science Ltd Self certified EC Type Examination Certificate(s)
Baseefa05ATEX0277 latest supplement Baseefa05ATEX0277/2 issued 24th November 2008
Ionscience09849 Examination certificate issued 4th September 2009
Ref Ion Science Cert Report 849237, 849242
International Standards
IECEx BAS 06.0057 latest revision no.1 issued 20th November 2008
Ref Baseefa Cert Report 05(c)0423, 06(c)0614, 08(c)0578
Ex ia IIC T4 (-20oC Ta + +50oC)
Standards
BS EN 60079-0:2006 Electrical Apparatus for Potentially Explosive Atmospheres – General Requirement
BS EN 60079-11:2007 Explosive Atmospheres - Equipment Protection by Intrinsic Safety ‘i’
BS EN 60079-15:2007 Explosive Atmospheres - Equipment Protection by other means ‘n’
BS EN 61010-1:2010 Safety requirements for electrical equipment for measurement, control and
laboratory use – General requirements
Directive 2004/108EC Electrical Equipment – Electromagnetic Compatibility (EMC)
EN61000-6-3:2007 Class 1 (light industrial and domestic) Electromagnetic Compatibility (EMC) Generic
standards. Emission standard for residential, commercial and light industrial
environments
EN50270:2006 Electromagnetic compatibility. Electrical apparatus for the detection and
measurement of combustible gases, toxic gases or oxygen.
Other Standards
BS EN ISO 9001:2008 Quality Management Systems – Requirements
BS EN 13980:2002 Potentially Explosive Atmospheres – Application of Quality Systems
On behalf of Ion Science Ltd, I declare that, on the date this product accompanied by this declaration is
placed on the market, the product conforms to all technical and regulatory requirements of the above listed
directives.
Name:Mark Stockdale Position: Technical Director
Signature: Date: 20th November 2009

TVOC MANUAL Ion Science Ltd
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Contents
Declaration of conformity .............................................................................................................................. 3!
Statements ...................................................................................................................................................... 5!
Responsibility for use .................................................................................................................................... 5!
Quality assurance ......................................................................................................................................... 5!
Disposal ........................................................................................................................................................ 5!
Legal Notice .................................................................................................................................................. 5!
Introduction to TVOC...................................................................................................................................... 6!
Packing list...................................................................................................................................................... 8!
Standard TVOC instrument........................................................................................................................... 8!
TVOC Calibration Tool Kit............................................................................................................................. 8!
TVOC setup ..................................................................................................................................................... 9!
Selector Pins ................................................................................................................................................. 9!
Duty Cycle................................................................................................................................................... 10!
Installation ..................................................................................................................................................... 11!
Location....................................................................................................................................................... 11!
Cable and gland requirements .................................................................................................................... 11!
Dimensions for mounting ............................................................................................................................ 12!
Power requirements .................................................................................................................................... 13!
Initial calibration .......................................................................................................................................... 15!
Operation....................................................................................................................................................... 16!
Start Up ....................................................................................................................................................... 16!
Adjusting the Duty Cycle ............................................................................................................................. 16!
LED’s........................................................................................................................................................... 17!
Selector pins ............................................................................................................................................... 17!
Calibration mode ......................................................................................................................................... 17!
Calibration gases ........................................................................................................................................ 17!
Calibration routine ....................................................................................................................................... 18!
Setting the ZERO ........................................................................................................................................ 18!
Setting the gas concentration (The actual value that the calibration has been supplied at) ....................... 19!
Setting the SPAN ........................................................................................................................................ 19!
Maintenance .................................................................................................................................................. 21!
Cleaning / replacing the lamp...................................................................................................................... 21!
Fuse rupture and replacement .................................................................................................................... 23!
Lamp Warranty Statement .......................................................................................................................... 23!
System recommendations ........................................................................................................................... 24!
Remote area monitoring.............................................................................................................................. 24!
Gas sample systems................................................................................................................................... 24!
Instrument warranty and service ................................................................................................................ 26!
Warranty...................................................................................................................................................... 26!
Service ........................................................................................................................................................ 26!
Contact details ............................................................................................................................................ 26!
Diagnostics.................................................................................................................................................... 27!
F4 errors...................................................................................................................................................... 28!
Technical specifications .............................................................................................................................. 30!
Manual log ..................................................................................................................................................... 31!

TVOC MANUAL Ion Science Ltd
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Statements
Responsibility for use
TVOC detects a large range of gases, which are potentially dangerous from both a poisoning and/or an
explosive perspective. TVOC has a number of selectable features allowing the detector to be used in a
variety of applications. Ion Science Ltd can accept no responsibility for the incorrect adjustment of features
that cause harm or damage to persons or property. It is the users’ responsibility to respond appropriately to
the readings delivered.
Inadequate performance of the gas detection equipment described in this manual may not necessarily be
self-evident and consequently equipment must be regularly inspected and maintained. Ion Science
recommends that personnel responsible for equipment use institute a regime of regular checks to ensure it
performs within calibration limits, and that a record be maintained which logs calibration check data. The
equipment should be used in accordance with this manual, and in compliance with local safety standards.
Warning
1. Substitution of components may impair intrinsic safety and result in unsafe conditions.
2. For reasons of safety, TVOC must only be operated and serviced by qualified personnel.
3. Please read and understand this user manual fully before installing, operating or servicing TVOC.
Quality assurance
TVOC has been manufactured in compliance with ISO9001:2008, which ensures that the equipment
supplied to our customers has been designed and assembled reproducibly, from traceable components, and
leaves Ion Science calibrated to stated standards.
Disposal
Dispose of TVOC and its components in accordance with all local and national safety and environmental
requirements. This includes the European WEEE (Waste Electrical and Electronic Equipment) directive. Ion
Science Ltd offers a take back service. Please contact us for more information.
Legal Notice
Whilst every attempt is made to ensure the accuracy of the information contained in this manual, Ion Science
accepts no liability for errors or omissions, or any consequences deriving from the use of information
contained herein. It is provided "as is" and without any representation, term, condition or warranty of any
kind, either express or implied. To the extent permitted by law, Ion Science shall not be liable to any person
or entity for any loss or damage which may arise from the use of this manual. We reserve the right at any
time and without any notice to remove, amend or vary any of the content which appears herein.

TVOC MANUAL Ion Science Ltd
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Introduction to TVOC
TVOC is a fixed continuous monitor for the detection and measurement of total volatile organic compounds,
which can be dangerous from both a poisoning and explosive perspective. Total VOC’s are detected using
PID (Photo ionisation detection) technology.
TVOC has a number of user selectable features which define its operation and will be application dependent.
The user can define the detection ranges or 0.01 - 10ppm, 0.1 – 100 ppm or 1 – 1,000 ppm (Default);
detection units, either ppm or mg/m3; and the duty cycle time i.e. the frequency that the instrument takes a
measurement. Duty cycles are explained in more detail under TVOC set up, and Operation.
IMPORTANT: TVOC can be calibrated on alternative gases to Isobutylene however to ensure TVOC
remains within specification, the correct concentration for the alternative gas must be chosen.
Example: Benzene gas has a response factor of 0.5 which means only half as much concentration is
required to produce the equivalent to Isobutylene.
The ideal gas / concentrations used to set the calibration SPAN are shown below:-
Lower limit Upper limit
10 ppm range 8 ppm 12 ppm Isobutylene equivalent
100 ppm range 90 ppm 110 ppm Isobutylene equivalent
1,000 ppm range 90 ppm 110 ppm Isobutylene equivalent
How to calculate alternative concentration of gases for gases other than Isobutylene:-
Calibration Ideal response Response factor Ideal calibration gas
Gas for Isobutylene concentration
Benzene 100 x 0.5 = 50 ppm
Isoprene 100 x 0.7 = 70 ppm
Isobutylene 100 x 1.0 = 100 ppm
Carbon disulfide 100 x 1.4 = 140 ppm
Ethyl acrylate 100 x 2.0 = 200 ppm
For other gas response factors please refer to the Ion Science web site or contact Ion Science Ltd.
http://www.ionscience.com/GasSearch/tabid/87/Default.aspx
WARNING: Ignoring these guide lines may result in calibration failure, loss of resolution or loss of range.
The default settings of TVOC are:
Detection range – 1 – 1000 ppm
Units - ppm
Signal update - 60 seconds
TVOC gives a continuous 4-20 mA output which can be integrated into a DCS control system to give an
indication of VOC levels in the operating environment. Note the 4-20 mA output must be externally powered
with 8-35 V.
In addition to the 4-20 mA output TVOC has an LCD display showing gas concentration and 4 colour LED’s.
LED functions are as follows:
Green - is an indicator of TVOC’s working status
Red - is the fault indicator
Yellow x 2 - are calibration status indicators
Please see Calibration for more information on LED status.

TVOC MANUAL Ion Science Ltd
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Introduction to TVOC
For installation requirements please refer to Installation and Technical Specification of this manual. Before
attempting an installation, please fully read and understand this user manual, and for hazardous area (IS)
installations please also refer to the TVOC Intrinsically safe certificate for further details.
The TVOC safety rating permits its deployment in all hazardous areas of the quoted (or less demanding)
rating. For detail please refer to the marking on your instrument (found on the front main label). As of 1st of
October units will be manufactured with two protection concepts applied by separate certifications. Intrinsic
safety (ia) and Non sparking (nA). All units manufactured up to that date will only have intrinsic safety.
a) Intrinsic Safety (ia) permits the deployment in areas where explosive gases (of group IIA, IIB and IIC) are
intermittently present (zone 1) with an ambient temperature range of -20 to 50°C. Intrinsically safe
installations will require the use of safety barriers and appropriate wiring.
b) Non sparking (nA) permits deployment in areas where explosive gases (of group IIA, IIB, IIC) are unlikely
but possible (Zone 2) with ambient temp range of -20°C to 50°C. Non sparking installations do not require
safety barriers however the maximum working voltage should be strictly adhered to as a matter of safety. As
no safety barriers are required there is complete flexibility on the implementation of a three wire system.
TVOC does require regular calibration onsite please see the Calibration section for more information. TVOC
calibration mode is accessed via a magnetic on site switch system.

TVOC MANUAL Ion Science Ltd
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Packing list
All items of equipment shipped by Ion Science Ltd are packed in suitable containers and enclosed in a shock
absorbing filling which affords a considerable degree of protection against physical damage.
Contents should be carefully removed and checked against the packing list. Any discrepancies between the
contents and the packing list must be reported to Ion Science Ltd within ten days of receipt of shipment. Ion
Science cannot be held responsible for shortages not reported with in the period.
Standard TVOC instrument
Item Description Qty
1. TVOC instrument 1
2. Cable gland M20 (Intrinsically Safe Certified) 2
3. Blanking plug M20 intrinsically (Intrinsically Safe Certified) 1
4. TVOC Manual 1
TVOC Calibration Tool Kit
Item Description Qty
1. Calibration magnet 1
2. Calibration adaptor 1
3. Calibration connector 1
4. Aspirator 1
5. Carbon filter 1
6. Allen keys 1
3. Calibration
connector
1. Calibration
magnet
6. Allen keys X 2
4. Aspirator
2. Calibration
adaptor
5. Carbon
filter
Diagram 1

TVOC MANUAL Ion Science Ltd
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Diagram 3
TVOC setup
Selector Pins
TVOC has a number of settings that can be selected by the
user via a row of four selector pins mounted on the reverse side
of the main PCB. Diagram 2 shows the location of the functional
selector pins labelled - A, B, C & D.
The selector pins absence or presence determines the chosen
setting.
TVOC is shipped with all four selector pins fitted as shown in
diagram 3.
Diagram 4 shows the removal of 1 selector pin.
The following table shows the selector pin combinations and the corresponding function.
!= Selector pin fitted "= Selector pin removed
Selector pin
A B C D Range Displayed units
!!!!1000 ppm (Default)
!!x!100 ppm
!x!!10 ppm
!!!x2280 mg/m3
!!xx228 mg/m3
!x!x22.8 mg/m3
Selector pin ‘B’ and ‘C’ selects the ranges - 10 ppm, 100 ppm or 1000 ppm
Selector pin ‘D’ selects the units - ppm’ or ‘mg/m3
Selector pin ‘A’ - Fault output range
NOTE: During an Alarm condition (F1 or F2) the output will drop to either 3.5 mA or 2.0 mA.
Jumper ‘A’ fitted: 3.5 mA during an alarm condition
Jumper ‘A’ removed: 2.0 mA during an alarm condition.
As default, the TVOC has a 100 ppm factory calibration
Diagram 2
Diagram 4

TVOC MANUAL Ion Science Ltd
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TVOC setup
NOTE: * TVOC is shipped with ALL selector pins fitted as standard
* TVOC only reads the selector pin settings when power is connected.
Always ensure power is disconnected from TVOC before changing
setting or carrying out maintenance.
* Never place selector pins on the programming port connector.
* Ensure static build up is discharged before touching components.
* If the jumper selection is not a recognised option then error F4 will occur. To recover switch
the instrument off perform the correct jumper selection and switch the instrument back on.
Duty Cycle
The life of a photoionization lamp is used up when the lamp is illuminated, the lamp window can also
contaminate resulting in a reduced level of detection. The TVOC pulses the lamp on and off which extends
lamp life and reduces lamp contamination. This in turn can increase the time between servicing.
The TVOC switches on the lamp, takes a reading and then
updates the 4-20 mA output and display screen. The default Duty
Cycle is the frequency between test cycles, the factory default is
set to 1 minute however this time can be adjusted from 0 to 5
minutes.
Please note: When bump testing after a calibration the response
may be delayed depending on when in the gas is applied during
the test cycle.
Fast response mode
The TVOC can be set to Fast Response Mode, when selected the TVOC will update the output every one
second. Fast response mode can be selected by setting both the seconds and minutes to zero.
Please note: The warrantee of Ion Science PID lamps is based upon a duty cycle of 1 minute. Lamps used
with Duty Cycle below one minute will not be covered under the standard warrantee terms.

TVOC MANUAL Ion Science Ltd
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Installation
Location
There are many variables involved in defining the optimum location for a gas detector. Obvious though it
may sound, the most important rule is:
•A detector will not detect gas unless gas actually reaches the detector.
•TVOC should be mounted in the location most likely to detect gas.
•TVOC must be mounted vertically with the sensor underneath the case. This avoids dust and debris
blocking the access to the detector cell.
•If possible, mount TVOC near the ceiling to target VOC gases that are lighter than air or just above
floor level to detect VOC gases that are heavier than air.
•Mount TVOC in an area that has good air circulation. Restricting natural air current may result in
delayed detection.
•Never mount TVOC in direct sunlight or over a heat source such as a radiator. This may cause TVOC
to exceed its certified working temperature range.
•Do not mount TVOC in areas likely to flood.
•Mount TVOC’s in areas that are easily accessible for servicing.
•Percentage variations in the composition of air (78% Nitrogen, 21% Oxygen and 1% Argon) may affect
the detected signal.
Please refer to the technical specifications of the instrument under Technical Specifications of this
manual before beginning a TVOC installation.
Cable and gland requirements
The Screw terminal sockets for connecting wires in the TVOC accept wires of 0.5mm2to 2.5mm2
C.S.A.
Screened cables for both power and signal out are necessary to achieve EMC compliance. Cable
screens must be terminated at both ends for them to be effective in achieving electromagnetic
compatibility (EMC). The screens should be terminated to the TVOC enclosure using EMC
compatible cable glands. It is important for an EMC compatible gland to make electrical contact to the
enclosure. This is usually done using a serrated washer or EMC lock nut that bites through the paint
making electrical contact. EMC lock nuts have been provided. These locknuts are orientation specific
the points should be facing against the case in order to cut through the paint during tightening.
Two M20 cable glands and one blanking plug have been supplied as standard to ease installation in
most circumstances. These parts will not be appropriate for all applications so they should be used at
the discretion of the installation engineer. It is recommended that the manufacturer’s instructions are
followed for the gland and blanking plug installation. The M20 blanking plug has been included to
enable installations using a single entry cable (for example a three wire system) to be implemented.
While Ion Science can not recommend the cable gland suitable for every application the following
information may be useful to the installation engineer for the selection of the appropriate cable gland.
•For intrinsically safe operation using safety barriers, the only requirements on the cable
glands are that they are better than IP20 rated. This may seem extraordinary however
where the power is safely limited to the TVOC it is intrinsically safe so does not rely on the
prevention of dirt or moisture into the enclosure.
•For intrinsically safe operation in Zone 2 without safety barriers, cable glands must be ATEX
or IECX rated (Ex e, Ex n or Ex d) and at least IP54.
Installation of the TVOC depends on preferences of the installer, intrinsically safe operating legislation and
the application.
Ion Science suggests connecting the screens from cables via a gland as shown on the diagrams and under
Installation Section of this manual. There may however be technical circumstances where connection to the
PCB is necessary.

TVOC MANUAL Ion Science Ltd
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Installation
Dimensions for mounting
Diagram 5

TVOC MANUAL Ion Science Ltd
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Installation
NOTE: The TVOC case can be used as a template when marking out fixing holes but do not drill
through the fixing holes.
Power requirements
Non Intrinsically Safe Operation applications:
Input power 5-28 Vdc. 80 mA max. (0.5 to 2.5 mm2C.S.A.)
Output power (4-20mA) 8-35 Vdc. 80 mA max. (0.5 to 2.5 mm2C.S.A.)
Note: 4-20mA loop must be externally powered.
4 Wire System
(Non IS)
3 Wire System
(Non IS)
Diagram 6
Diagram 7

TVOC MANUAL Ion Science Ltd
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Installation – Hazardous location
Warning!
The label on the enclosure details the IS and nA certifications. The appropriate section of the Intrinsically
Safe label should be covered up or blocked out to reflect the type of installation. For Non-intrinsically Safe
applications the label should be covered completely. For Intrinsically Safe (IS) Zone 2 applications with out
safety barriers the ia certification details should be blanked out. For Zone 1 or Zone 2 IS applications with
safety barriers the nA certification details should be covered. This will prevent safety discrepancies and or
mis-use in the future should the equipment be moved or the site be re-defined as a hazardous area.
Entry parameters for intrinsically safe Zone 2, nA (non-sparking) areas only:
Input power 5-24 Vdc, 80 mA max
Output power (4-20 mA) 8-35 Vdc, 22 mA
For information only: please see Intrinsically Safe operation certificate before installation.
The wiring of Intrinsically Safe systems is identical to the wiring showing for non Intrinsically Safe
applications. The only difference is the requirements to ensure that the power supplied used provides 24 V
or less in normal operation.
Intrinsically Safe (IS) applications: Entry parameters
Input power Ui = 18V Ii = 800mA Pi = 1.2W Ci = 0µF Li = 0mH
Output power(4-20mA) Ui = 30V Ii = 200mA Pi = 1.2W Ci = 0µF Li = 0mH
For information only please see Intrinsically Safe certificate before installation
Ion Science Ltd suggest using the following zener barriers for IS approved applications. Use competent
installation engineers and ask them for installation and application advice.
Note
•All cable lengths are estimated for Zone 1 IIC installation of the equipment
•Using 1 mm2C.S.A conductor S.T.P cables with capacitance per meter of 250 pF/m, L/R ratio of 25
muH/Ωconductor resistance at 20°C of 18.4 Ω/km.
•Calculation assumes cables are at 50°C.
Warning! Intrinsically Safe (IS) applications
•Units should not be powered using non IS power supplies prior to installation in an IS application.
•If non IS power is supplied the unit will require inspection by Ion Science Ltd or an Ion Science Approved
Service Centre prior to installation in an IS application.
•TVOC fuses may not be replaced in the field.
•If a fuse is blown TVOC will require inspection by Ion Science Ltd or and Ion Science Approved Service
Centre before it is used in an IS application.

TVOC MANUAL Ion Science Ltd
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Installation – Hazardous location
4-wire Control equipment sensing 4 – 20 mA on return line
Notes:
!For intrinsically safe installations, the enclosure may be opened while the system is live,
provided the work is undertaken by competent personal and suitable safety precautions are
taken. This overrides the warning on the enclosure label.
Initial calibration
TVOC is calibrated at Ion Science before dispatch using 100 ppm Isobutylene. However, if you wish to
calibrate your TVOC after installation, Ion Science recommends that the TVOC is left to run on its chosen
settings (see ‘TVOC Setup Section’) for 24 hours before an initial calibration is carried out, to allow the
instrument to stabilise.
Diagram 8

TVOC MANUAL Ion Science Ltd
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Operation
Start Up
After electrical power is connected, TVOC runs through a ‘Start up’ routine, which lasts for approximately 1
minute. During this ‘Start up’ routine TVOC demonstrates the following characteristics:
* The LCD screen displays the software version number
* The GREEN LED flashes
* The 4-20 mA output is set to 4 mA (0.0 ppm)
NOTE: If the 0-10 ppm range is selected the TVOC will require calibration using 10ppm Isobutylene before
use (See the calibration section of this manual)
During this ‘Start-up’ time the user can adjust the Duty Cycle time as referred to in ‘TVOC Setup’ under the
Duty Cycle section. This time can be adjusted from 0 to 5 minutes in 10 second increments.
Adjusting the Duty Cycle
NOTE: Please read this entire procedure before attempting to adjust the lamp OFF time.
There are two stages to adjusting the Duty Cycle time. The first stage adjusts the seconds 0 to 59 seconds,
the second stage adjusts from 0 to 5 minutes. Please see the description of the Duty Cycle on page 10.
1. During the 1 minute ‘Start up’ time place the calibration magnet over the top
right hand corner of the Ion Science logo. (See diagram 9) Two numbers on the
right of the LCD screen will flash.
Diagram 9
2. While the magnet is held in this position the number on screen will roll over from 00
through to 50 in 10 second steps. Quickly remove the magnet when the desired time
appears.
3. After 5 seconds the TVOC will move on to the next stage. (Reapply the magnet
within 5 seconds if further adjustment is necessary)
4. The TVOC will move to the next stage indicated by a digit appearing on the left of
the screen. Holding the magnet in place will cause this number to roll over from 0 to 5
minutes. Quickly remove the magnet when the desired time appears.
5. After 5 seconds the TVOC will display both the minutes and seconds selected.
(Reapply the magnet within 5 seconds if further adjustment is necessary)
6. TVOC will restart the start-up sequence and then enter running mode. The Duty
cycle is then saved to memory. The duty cycle will be remembered through a power
cycle.
Fast response mode
If the Duty Cycle time is adjusted lower than 0:10 (10 seconds) the instrument will update the output every
one second. In this mode of operation the F2 fault condition is disabled. This means that removal of the
sensor may go undetected.

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Operation
LED’s
see Diagram 12
The green indicates TVOC’s working status:
ON Indicates the PID lamp is OFF
Flashing Indicates the PID lamp is ON
A red indicates fault status:
ON Indicates TVOC cannot function correctly. The 4-20mA output drops
to 3.5mA.
URGENT attention is required.
Flashing Indicates the TVOC cannot function but a reading is being
attempted
A yellow Zero LED indicates during normal operation
ON Last calibration zero level was outside expected limits
(The instrument will operate normally with the previous calibration)
A yellow Span LED indicates during normal operation
ON Last calibration Span level was outside expected limits
(The instrument will operate normally with the previous calibration)
Please see Section 7 Calibration for YELLOW LED status.
Selector pins
TVOC has a range of options that are selected via the selector pins on the back of the main PCB (please see
the ‘TVOC Set up’ Section).
The options are shown below with the defaults highlighted in bold:
1-1000 ppm or 0.01 – 10 ppm or 0.1 – 100 ppm
ppm units or mg/m3units
Calibration mode
TVOC calibration mode can be accessed using the calibration
magnet supplied in the TVOC calibration tool kit (Part number: A-
845214).
To enter calibration place the magnet over the top right of the Ion
Science Logo until the state changes (i.e. an LED illuminates and/or
the display changes).
Ensure the magnet is withdrawn away from the magnetic switch by
at least 1 cm once a change has occurred.
Calibration gases
TVOC has three (3) ranges that can be selected however the 0-
10ppm range requires the instrument is calibrated by the user before
use. The 0-100ppm and the 0-1000 ppm ranges can initially run
using the Factory calibration carried out during the instruments
manufacture, however because the 0-10 ppm range is more
sensitive and more susceptible to environmental and system
tolerances the instrument must be calibrated before use.
If the 0-10 ppm range is selected TVOC will display the following
screen to indicate that a calibration is required before it can be used.
Follow the calibration instructions before use.
Diagram 10
Diagram 11

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Hand aspirator
Calibration
Calibration routine
Ion Science recommends calibrating TVOC after any maintenance or lamp cleaning is carried out and on a 3
monthly basis to ensure TVOC is working to specification.
NOTE: Please read this entire calibration procedure before attempting a calibration.
TVOC calibration is undertaken in four steps:
1. Setting the ZERO (Using clean gas via carbon filter)
2. Setting the gas tolerance (1 – 200 ppm Isobutylene on 0-100 ppm and 0-1000 ppm ranges)
(0.1 – 20.0 ppm Isobutylene on the 0-10ppm range)
3. Setting the SPAN (Using the SPAN gas)
Setting the ZERO
1 – Place the calibration magnet over the top right hand corner of the Ion Science logo to enter
calibration mode. The ‘ZERO LED’will illuminate and the ‘STATUS LED’will extinguish.
2 – Remove the calibration magnet
3 – Insert the calibration adaptor into the sensor cap, attach the carbon filter to the calibration adaptor.
The carbon filter should be attached to the hand aspirator.
4 – Again place the calibration magnet over the logo. The ‘ZERO LED’will flash, during this stage
TVOC displays a direct millivolt (mV) output from the PID sensor.
STATUS LED
ZERO LED
SPAN LED
FAULT LED
Calibration adaptor
Carbon filter
Diagram 12: LED’s
STATUS, ZERO, SPAN, FAULT
Diagram 13

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Calibration
5 - Slowly and repeatedly squeeze the hand aspirator to push clean air through the carbon filter and past
the PID sensor. The ‘ZERO LED’ will stop flashing after approximately 2 minutes.
6 – Now remove the equipment except for the calibration adaptor.
NB During the above process the 'mV' reading on the display must fall below 30 mV to pass the Calibration
stage.
An acceptable ZERO calibration level will result in the illumination of the ‘STATUS LED’.
An unacceptable ZERO calibration level will result in the illumination of the ‘FAULT LE’D.Should this occur
the TVOC will not proceed to the gas tolerance setting and return to normal operation the previous
calibration levels will be used. The Yellow ‘ZERO LED’will be illuminated to indicate the failure to set a zero
calibration level.
Setting the gas concentration (The actual value that the calibration has been supplied at)
1 Now, again place the calibration magnet over the corner of the logo –
The GREEN or FAULT LED will be extinguished and the numeric
display will start to flash.
2 If the 0-10ppm range is selected you will be able to adjust between 1.0 ppm and 100ppm, for both
the 100 ppm and 1000 ppm ranges a concentration of between 1 and 200 ppm can be selected.
Leaving the magnet in position will cause the displayed number to cycle through the concentration,
remove the magnet when the displayed value matches that stated on the Calibration gas bottle.
Should you miss the desired reading quickly reapply the magnet to continue scrolling through the
numbers and remove the magnet at the desired figure.
The selected number will be recorded 5 seconds after the removal of the magnet when the display
stops flashing. The display will initially show 90, should this be the desired figure remove the magnet
straight away.
Setting the SPAN
1 Connect the SPAN gas to the calibration connector then the connector to the adaptor. Do not over
tighten the Luer fitting; only a one quarter turn is required.
Switch on the gas supply and then place the magnet over the logo.
The SPAN LED will flash and TVOC will display the direct millivolt (mV) output from the PID sensor.
Now remove the magnet.
Calibration adaptor
SPAN gas
Calibration connector
Diagram 14

TVOC MANUAL Ion Science Ltd
Page 20 of 32
Unrivalled Detection. www.ionscience.com
2 The SPAN LED will stop flashing after approximately 2 minutes.
3 Turn off the gas and disconnect the equipment
Calibration
NB during the span measurement process the mV reading of the span must be greater than the zero level to
pass the ZERO calibration stage.
An acceptable SPAN calibration level will result in the illumination of the green STATUS LED.
An unacceptable SPAN calibration level will result in the illumination of the red FAULT LED. Should this
occur the previous calibration levels will be used when the instrument returns to normal operation. The
Yellow span LED will be illuminated to indicate the failure to calibrate the span.
Now place the magnet over the logo corner to return to normal monitoring routine.
The GREEN LED will start flashing as TVOC starts its cycle with a lamp ON cycle.
IMPOTANT: Unacceptable calibration levels will not be adopted; the instrument will default to the
previously stored acceptable calibration factor.
NOTE:
* Always check the accuracy of your calibration by checking readings from TVOC when it is running
normally using the ZERO filter and SPAN gas.
* Accuracy of calibration is the responsibility of the person carrying out the calibration. If in doubt seek
advice.
* TVOC must be calibrated after lamp/cell cleaning or general maintenance.
NOTE: Causes of contamination and error in signal:
* Changes in air pressure when detecting ppm concentration
* Variation in oxygen, argon beyond ambient levels.
* Variation in ambient moisture content.