wtw Oxi 330i User manual

ba52306e04 03/2008
Handheld meter
Oxi 330i/340i
Operating manual
Oxygen measuring instrument
AR
STO
CAL
RCL
M
O
6
7
1
92
7
O
°
C
mg/l
ARng
TP

Oxi 330i/340i
2ba52306e04 03/2008
Accuracy when
going to press
The use of advanced technology and the high quality standard of our instru-
ments are the result of continuous development. This may result in differenc-
es between this operating manual and your instrument. Also, we cannot
guarantee that there are absolutely no errors in this manual. Therefore, we
are sure you will understand that we cannot accept any legal claims resulting
from the data, figures or descriptions.
Warranty We guarantee the instrument described for 3 years from the date of pur-
chase.
The instrument warranty covers manufacturing faults that are discovered
within the warranty period. The warranty does not cover components that are
replaced during maintenance work, e.g. batteries.
The warranty claim extends to restoring the instrument to readiness for use
but not, however, to any further claim for damages. Improper handling or un-
authorized opening of the instrument invalidates any warranty claim.
To ascertain the warranty liability, return the instrument and proof of pur-
chase together with the date of purchase freight paid or prepaid.
Copyright ©Weilheim 2008, WTW GmbH
Reproduction in whole - or even in part - is prohibited without the express writ-
ten permission of WTW GmbH, Weilheim.
Printed in Germany.

Oxi 330i/340i List of contents
3
ba52306e04 03/2008
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 SETs of equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.4 Jack field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 General safety instructions . . . . . . . . . . . . . . . . . . . . . . . 10
3 Commissioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 Initial commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Switching on the measuring instrument . . . . . . . . . . . . . 13
4.2 Measuring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2.1 General information . . . . . . . . . . . . . . . . . . . . . . 14
4.2.2 Measuring the D. O. concentration . . . . . . . . . . 15
4.2.3 Measuring the D. O. saturation . . . . . . . . . . . . . 16
4.2.4 Measuring the D. O. partial pressure . . . . . . . . 16
4.2.5 Selecting the measuring range, AutoRange . . . 17
4.2.6 AutoRead AR (drift control) . . . . . . . . . . . . . . . . 18
4.3 Calibrating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3.1 Calibrating with the air calibration vessel . . . . . 21
4.3.2 Calibrating via a comparison measurement . . . 23
4.3.3 Entering the salt content (salinity) . . . . . . . . . . . 25
4.4 Saving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.4.1 Saving manually . . . . . . . . . . . . . . . . . . . . . . . . 26
4.4.2 Saving automatically . . . . . . . . . . . . . . . . . . . . . 28
4.4.3 Outputting the data storage . . . . . . . . . . . . . . . . 30
4.4.4 Clearing the memory . . . . . . . . . . . . . . . . . . . . . 34
4.5 Transmitting data (only Oxi 340i) . . . . . . . . . . . . . . . . . . 35
4.5.1 Data transmission interval (Int 2, Oxi 340i) . . . . 35
4.5.2 Recorder (analog output, Oxi 340i) . . . . . . . . . . 37
4.5.3 PC/external printer (RS 232 interface, Oxi 340i) 38
4.5.4 Remote control (Oxi 340i) . . . . . . . . . . . . . . . . . 38
4.6 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4.7 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5 Maintenance, cleaning, disposal. . . . . . . . . . . . . . . . . 45
5.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
5.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
5.3 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

List of contents Oxi 330i/340i
4ba52306e04 03/2008
6 What to do if... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
7 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
8 Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Oxi 330i/340i Overview
5
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1 Overview
The compact precision handheld meter Oxi 330i/340i enables you to carry
out oxygen (D. O.) measurements rapidly and reliably.
The Oxi330i/340i handheld meter provides the maximum degree of operating
comfort, reliability and measuring certainty for all applications.
The proven OxiCal®calibration procedure and the special AutoRead func-
tion support you in your work with the Oxi handheld meter.
Note
If you need further information or application notes, you can obtain the follow-
ing material from WTW:
zApplication reports
zPrimers
zSafety datasheets.
You will find information on available literature in the WTW catalog or via the
Internet.
1Keypad
2Sample display
3Jack field
AR
M
O
6
7
1
92
7
O
°
C
mg/l
ARng
TP
RCL
STO
CAL
1
2
3

Overview Oxi 330i/340i
6ba52306e04 03/2008
1.1 SETs of equipment
The measuring instrument is also available as part of individual SETs of
equipment. You will find additional information on this and other accessories
in the WTW catalog or via the Internet.
Set (sample configuration):
1 Measuring instrument, Oxi 330i/340i
2 Stand
3 – 50 ml ELY/G electrolyte solution for D.O. probes
– 50 ml RL/G cleaning solution for D.O. probes
– 3 WP 90/3 exchange membrane heads
– SF300 abrasive film for D.O. probes
4 CellOx 325 D.O. probe with calibration vessel
5 Plug-in power supply, optional (340i only)
5
4
3
2
1

Oxi 330i/340i Overview
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1.2 Keypad
Key functions
RUN/ENTER
ARRCLCAL
STOM
Select the measuring mode <M>:
– D. O. concentration
– D. O. saturation
– D. O. partial pressure
Save a measured value
<STO>
Switch measuring instrument on/off
<ON/OFF>
Calibration; Select the calibration procedure
<CAL>
Display/transmit measured values
<RCL>
Activate/deactivate the AutoRead function
<AR>
Switch on the salt content correction,
Increase values, scroll
<▲>
Switch off the salt content correction,
Decrease values, scroll
<▼>
Confirm entries, start AutoRead
<RUN/ENTER>
M
STO
CAL
RCL
AR
RUN/ENTER

Overview Oxi 330i/340i
8ba52306e04 03/2008
1.3 Display
1.4 Jack field
Warning
Only connect probes to the measuring instrument that cannot return any volt-
ages or currents that are not allowed
(> SELV and > current circuit with current limiting).
Nearly all probes - especially WTW probes - fulfill these conditions.
1D. O. probe
2Plug-in power supply (optional) - Oxi 340i only
3Serial interface RS 232 / analog output (recorder) ,
Oxi 340i only
AutoCal DIN
AutoCal TEC
mV/pH
1/
cm
K
/
%
°
F
TDS
UpH Sal
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
RCL
Auto
Store
Time
Baud
Day.Month No.
Ident
Year
S
8
8.
8
88
8
O
C
%
mg/l
LoBat
ARng AR
TP
1
Cal
°
mbar
Sal
Status display
Meas. value display
Function and
temperature display
Sensor symbol
3
12

Oxi 330i/340i Safety
9
ba52306e04 03/2008
2Safety
This operating manual contains basic instructions that you must follow during
the commissioning, operation and maintenance of the measuring instrument.
Consequently, all responsible personnel must read this operating manual be-
fore working with the measuring system. The operating manual must always
be available within the vicinity of the measuring system.
Target group The measuring instrument was developed for work in the field and in the lab-
oratory.
We assume that, as a result of their professional training and experience, the
operators will know the necessary safety precautions to take when handling
chemicals.
Safety
instructions
The individual chapters of this operating manual use safety instructions such
as the label shown below to indicate various hazards or dangers:
Warning
indicates instructions that must be followed precisely in order to avoid the
possibility of slight injuries or damage to the instrument or the environment.
Further notes
Note
indicates notes that draw your attention to special features.
Note
indicates cross-references to other documents, e.g. operating manuals.
2.1 Authorized use
The authorized use of the measuring instrument consists exclusively of the
measurement of the dissolved oxygen (D. O.) content of liquid media in the
field and laboratory.
The technical specifications as given in chapter 7 TECHNICAL DATA must be
observed. Only the operation and running of the measuring instrument ac-
cording to the instructions given in this operating manual is authorized.
Any other use is considered to be unauthorized.

Safety Oxi 330i/340i
10 ba52306e04 03/2008
2.2 General safety instructions
This instrument is built and inspected according to the relevant guidelines
and norms for electronic measuring instruments (see chapter 7 TECHNICAL
DATA).
It left the factory in a safe and secure technical condition.
Function and
operating safety
The smooth functioning and operational safety of the measuring instrument
can only be guaranteed if the generally applicable safety measures and the
specific safety instructions in this operating manual are followed during oper-
ation.
The smooth functioning and operational safety of the measuring instrument
can only be guaranteed under the environmental conditions that are specified
in chapter 7 TECHNICAL DATA.
If the instrument was transported from a cold environment to a warm environ-
ment, the formation of condensate can lead to the faulty functioning of the in-
strument. In this event, wait until the temperature of the instrument reaches
room temperature before putting the instrument back into operation.
Safe operation If safe operation is no longer possible, the instrument must be taken out of
service and secured against inadvertent operation!
Safe operation is no longer possible if the measuring instrument:
zhas been damaged in transport
zhas been stored under adverse conditions for a lengthy period of time
zis visibly damaged
zno longer operates as described in this manual.
If you are in any doubt, please contact the supplier of the instrument.
Obligations of the
purchaser
The purchaser of the measuring instrument must ensure that the following
laws and guidelines are observed when using dangerous substances:
zEEC directives for protective labor legislation
zNational protective labor legislation
zSafety regulations
zSafety datasheets of the chemical manufacturers.

Oxi 330i/340i Commissioning
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3 Commissioning
3.1 Scope of delivery
zHandheld meter, Oxi 330i or 340i
zPlug-in power supply, optional (340i only)
zOperating manual and short operating manual
z4 batteries, 1.5 V Mignon type AA (in the instrument)
3.2 Initial commissioning
Perform the following activities:
zSet the date and time
zConnect the plug-in power supply, optional (340i only)
Setting the date
and time 1Press the <M> key and hold it down.
2 Press the <ON/OFF> key.
The display test appears briefly on the display.
3Press the <RUN/ENTER> key repeatedly until the date appears on
the display.
4 Set the date of the current day with <▲> <▼>.
5Confirm with <RUN/ENTER>.
The date (month) flashes in the display.
6 Set the current month with <▲> <▼>.
7Confirm with <RUN/ENTER>.
The year appears on the display.
8 Set the current year with <▲> <▼>.
9Confirm with <RUN/ENTER>.
The hours flash on the display.
10 Set the current time with <▲> <▼>.
11 Confirm with <RUN/ENTER>.
The minutes flash on the display.
12 Set the current time with <▲> <▼>.
13 Confirm with <RUN/ENTER>.
The instrument switches to the measuring mode, the sensor symbol
flashes.
14 Switch the instrument off using <ON/OFF>.

Commissioning Oxi 330i/340i
12 ba52306e04 03/2008
Connecting the
plug-in
power supply
(340i)
You can either operate the measuring instrument with batteries or with the
plug-in power supply. The plug-in power supply supplies the oxygen measur-
ing instrument 340i with low voltage (12 V DC). This saves the batteries.
Warning
The line voltage at the operating site must lie within the input voltage range
of the original plug-in power supply (see
chapter 7 TECHNICAL DATA).
Warning
Use original plug-in power supplies only (see
chapter 7 TECHNICAL DATA).
Note
You can also measure without the plug-in power supply. The functions of a
connected stirrer, however, can only be used when the plug-in power supply
is connected.
1Plug the jack (1) into the socket (2) of the measuring instrument.
2 Connect the original WTW plug-in power supply (3) to an easily ac-
cessible mains socket.
2
1
3

Oxi 330i/340i Operation
13
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4 Operation
4.1 Switching on the measuring instrument
Note
The measuring instrument has an energy saving feature to avoid unneces-
sary battery depletion. The energy saving feature switches the measuring in-
strument off if no key has been pressed for an hour. The energy saving
feature is not active when the AutoStore function is active.
Measuring
instrument 340i
The energy saving feature is also not active
zif the power is supplied by the plug-in power supply,
zif the communication cable and a PC with a running communication pro-
gram are connected,
zif the recorder cable is connected,
zif the printer cable is connected (for external printers).
1Connect the D. O. probe to the measuring instrument.
2 Press the <ON/OFF> key.
The display test appears briefly on the display.
The relative slope for the probe type that was just connected subse-
quently appears for approx. one second.
The measuring instrument then automatically switches to the mea-
suring mode that was last selected. The display shows the relevant
measured value.

Operation Oxi 330i/340i
14 ba52306e04 03/2008
4.2 Measuring
4.2.1 General information
You can measure the following variables:
zD. O. concentration
zD. O. saturation
zD. O. partial pressure
The measuring instrument is supplied with the following functions:
zAutoRange (automatic measurement range selection),
zThe AutoRead function (drift control) for checking the stability of the mea-
surement signal. This ensures the reproducibility of the measuring signal.
For details of how to switch the AutoRead function on/off, see section
4.2.6.
Preparatory
activities
Perform the following preparatory activities when you want to measure:
Note
Incorrect calibration of D. O. probes will result in incorrect measured values.
Calibrate at regular intervals.
Note
The Oxi 340i handheld oxygen meter automatically recognizes the type of
D.O. sensor that is connected (CellOx 325 or DurOx 325).
Temperature
sensor
The D. O. probe has an integrated temperature sensor that always measures
the current temperature of the test sample.
Warning
When connecting an earthed PC/printer, measurements cannot be per-
formed in earthed media as incorrect values would result. The RS 232 inter-
face is not galvanically isolated.
1Connect the D. O. probe to the measuring instrument.
2 In conjunction with the D. O. probe, check or calibrate the measuring
instument. How to calibrate is described in section 4.3.
3Select the measuring mode with <M>.

Oxi 330i/340i Operation
15
ba52306e04 03/2008
4.2.2 Measuring the D. O. concentration
Note
When measuring the concentration of test samples with a salt content of
more than 1 g/l, a salinity correction is required. For this, you have to measure
and input the salinity of the measured medium first. This is described in sec-
tion 4.3.3 ENTERING THE SALT CONTENT (SALINITY).
Before measuring the oxygen, you have to switch on the salt content correc-
tion (see below).
You can measure the oxygen content without a salt content correction as fol-
lows:
Switching on/off
the salt content
correction
Proceed as follows to switch on the salt content correction:
1Perform the preparatory activities according to section 4.2.1.
2 Immerse the D. O. probe in the test sample.
3Press the <M> key repeatedly until the D. O. concentration in mg/l
appears on the display.
ARng
%
LoBat Cal
AR
8
°
F
Sal
mbar
S
1
RCL
Auto
Store
1/
cm
/
K
%
TDS
UpH Sal
mV/pH
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
Time
Baud
Day.Month No.
Ident
Year
6
7
1
92
7
O
°
C
mg/l
TP
1In the D. O. concentration measuring mode, switch on the salt con-
tent correction with <▲>. The SAL display indicator appears on the
display. The value that was entered is taken into consideration dur-
ing the measurement (see section 4.3.3).
cm
cm
M
%
LoBat
Cal
AR
8
°
F
mbar
S
1
RCL
Auto
Store
1/
cm
/
K
%
TDS
UpH Sal
mV/pH
S/
m
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
Time
Baud
Day.Month No.
Ident
Year
6
7
1
42
5
O
°
C
mg/l
ARng
TP
Sal

Operation Oxi 330i/340i
16 ba52306e04 03/2008
4.2.3 Measuring the D. O. saturation
You can measure the D. O. saturation as follows:
4.2.4 Measuring the D. O. partial pressure
You can measure the D. O. partial pressure as follows:
2Switch the salt content correction off with <▼>. The SAL display in-
dicator is no longer displayed.
1Perform the preparatory activities according to section 4.2.1.
2 Immerse the D. O. probe in the test sample.
3Press the <M> key repeatedly until the saturation in %appears on the
display.
1Perform the preparatory activities according to section 4.2.1.
2 Immerse the D. O. probe in the test sample.
3Press the <M> key repeatedly until the partial pressure in mbar ap-
pears on the display.
mg/l
LoBat Cal
AR
8
°
F
Sal
mbar
S
1
RCL
Auto
Store
1/
cm
/
K
%
TDS
UpH Sal
mV/pH
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
Time
Baud
Day.Month No.
Ident
Year
6
7
1
92
8
O
°
C
ARng
TP
%

Oxi 330i/340i Operation
17
ba52306e04 03/2008
4.2.5 Selecting the measuring range, AutoRange
Sensors You can use the DurOx 325 or CellOx 325 sensors. If the automatic recogni-
tion function recognizes the DurOx 325 sensor, the measurement is carried
out at a lower resolution. The CellOx 325 sensor measures with a resolution
that is a factor of 10 higher.
AutoRange Each of the measuring parameters has 2 measuring ranges available. AutoR-
ange causes the measuring instrument to change to measuring range II if
measuring range I is exceeded, and also vice versa.
To switch the automatic measurement range selection on/off, see section
4.6 CONFIGURATION. When the AutoRange function is switched on, ARng ap-
pears on the display.
Measuring ranges/
resolutions with
CellOx 325 D. O.
probe
Measuring ranges/
resolutions with
DurOx 325 D. O.
probe
%
LoBat Cal
AR
8
°
F
Sal
mbar
S
1
RCL
Auto
Store
1/
cm
/
K
%
TDS
UpH Sal
mV/pH
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
Time
Baud
Day.Month No.
Ident
Year
6
7
1
92
7
O
°
C
mg/l
ARng
TP
mg/l % mbar
Measuring range I
Resolution
0 ... 19.99
0.01
0 ... 199.9
0.1
0 ... 199.9
0.1
Measuring range II
Resolution
0 ... 90.0
0.1
0 ... 600
1
0 ... 1250
1
mg/l % mbar
Measuring range I
Resolution
0 ... 19.9
0.1
0 ... 199
1
0 ... 199
1
Measuring range II
Resolution
0 ... 90
1
0 ... 600
1
0 ... 1250
1

Operation Oxi 330i/340i
18 ba52306e04 03/2008
4.2.6 AutoRead AR (drift control)
The AutoRead function (drift control) checks the stability of the measurement
signal. The stability has a considerable effect on the reproducibility of the
measured value.
Criteria With identical measurement conditions, the following applies:
1Select the measuring mode with <M>.
2 Activate the AutoRead function with <AR>. The current measured
value is frozen (hold function).
3Start AutoRead with <RUN/ENTER>.
The AR display indicator flashes until a stable measured value is
reached.
4If necessary, start the next AutoRead measurement with <RUN/EN-
TER>.
5 To terminate the AutoRead function: Press the <AR> key.
7
RCL
%
LoBat
Cal
8
°
F
Sal
mbar
S
1
Auto
Store
1/
cm
/K
%
TDS
UpH Sal
mV/pH
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
Time
Baud
Day.Month No.
Ident
Year
6
7
1
70
O
°
C
mg/l
TP
ARng AR
Parameter Reproducibility Response time
D. O. concentration better than 0.05 mg/l > 10 seconds
D. O. saturation index better than 0.6 % > 10 seconds
D. O. partial pressure better than 0.6 mbar > 10 seconds

Oxi 330i/340i Operation
19
ba52306e04 03/2008
4.3 Calibrating
Why calibrate? D. O. probes age. This changes the slope of the D. O. probe. Calibration de-
termines the current slope of the probe and stores this value in the instru-
ment.
Thus, you should calibrate at regular intervals.
Separate
calibration of
CellOx 325 and
DurOx 325
The Oxi 330i/340i handheld meter enables the two sensor types, CellOx 325
and DurOx 325, to be calibrated separately from one another. The calibration
of a specific sensor type does not affect the calibration of the other sensor
type. When connecting a sensor, the calibration data stored for the respective
sensor type are automatically used.
Calibration
procedures
The Oxi 330i/340i provides 2 calibration procedures:
zCalibration in water vapor-saturated air.
To calibrate the CellOx 325, use the OxiCal®-SL air calibration vessel (ac-
cessory), to calibrate the DurOx 325, use the OxiCal®-D air calibration
vessel (contained in the scope of delivery of the sensor).
zCalibration via a comparison measurement (e. g. Winkler titration accord-
ing to DIN EN 25813 or ISO 5813). At the same time, the relative slope is
adapted to the comparison measurement by a correction factor.
When to calibrate? zAfter connecting another D. O. probe
zIf the sensor symbol flashes, i. e. after the calibration interval has expired
Setting the
calibration interval
The calibration interval (Int 3) is set to 14 days in the factory. You can select
the interval in the range of 1 ... 999 days.
Printing the
calibration
record (340i)
The calibration protocol contains the calibration data of the current calibration.
You can transmit the calibration protocol to a printer via the serial interface
(see page 33).
8
LoBat
Time
Baud
Day.Month No.
Ident
Year
Sal
%
mbar
1
S
RCL
AR
Store
Auto
Cal
°
F
1/
cm
/
K
%
TDS
UpH Sal
mV/pH
S/
m
cm
cm
M
Lin
Tref25 Tref20
nLF
AutoCal DIN
AutoCal TEC
6
7
1
92
7
O
°
C
mg/l
ARng
TP

Operation Oxi 330i/340i
20 ba52306e04 03/2008
Note
You can automatically print a calibration protocol after the calibration. To do
so, connect a printer to the interface according to section 4.5.3 before cali-
brating. After a valid calibration, the record is printed.
Sample printout:
Sensor evaluation After the calibration, the measuring instrument evaluates the current status
of the sensor against the relative slope. The evaluation appears on the dis-
play. The relative slope has no effect on the measuring accuracy. Low values
indicate that the electrolytic filling will soon be depleted and the probe has to
be regenerated.
CALIBRATION PROTOCOL
02.03.99 14:19
Device No.: 12345678
CALIBRATION 02
Cal time: 02.03.99 / 14:19
Cal interval: 14d
OxiCal Tauto AR
Relative Slope: 0,88
Probe: +++
Display Relative slope
S = 0.8 ... 1.25
S = 0.7 ... 0.8
S = 0.6 ... 0.7
E3
Eliminate the error according to
chapter 6 WHAT TO DO IF...
S < 0.6 or S > 1.25