wtw Oxi 330i User manual

ba52306e01 02/2002
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

Accuracy when
going to press The use of advanced technology and the high quality standard of our instruments are the result of continuous development. This may result
in differences between this operating manual and your instrument. Al-
so, we cannot guarantee that there are absolutely no errors in this man-
ual. 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
purchase.
The instrument warranty covers manufacturing faults that are discov-
ered within the warranty period. The warranty does not cover compo-
nents 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 han-
dling or unauthorized opening of the instrument invalidates any warran-
ty claim.
To ascertain the warranty liability, return the instrument and proof of
purchase together with the date of purchase freight paid or prepaid.
Copyright ©Weilheim 2002, WTW GmbH & Co. KG
Reproduction in whole - or even in part - is prohibited without the ex-
press written permission of WTW GmbH, Weilheim & Co. KG.
Printed in Germany.

Oxi 330i/340i List of contents
3
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 (RS232 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
4
6 What to do if... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
7 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
8 Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Oxi 330i/340i Overview
5
1Overview
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 op-
erating comfort, reliability and measuring certainty for all applications.
The proven OxiCal®calibration procedure and the special AutoRead
function support you in your work with the Oxi handheld meter.
Note
If you need further information or application notes, you can obtain the
following material from WTW:
lApplication reports
lPrimers
lSafety 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
6
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 ac-
cessories 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
5Plug-in power supply, optional (340i only)

Oxi 330i/340i Overview
7
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
8
1.3 Display
1.4 Jack field
Warning
Only connect probes to the measuring instrument that cannot return
any voltages or currents that are not allowed (> SELV and > current cir-
cuit 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
2 Safety
This operating manual contains basic instructions that you must follow
during the commissioning, operation and maintenance of the measur-
ing instrument. Consequently, all responsible personnel must read this
operating manual before working with the measuring system. The op-
erating manual must always be available within the vicinity of the mea-
suring system.
Target group The measuring instrument was developed for work in the field and in
the laboratory.
We assume that, as a result of their professional training and experi-
ence, 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 envi-
ronment.
Further notes
Note
indicates notes that draw your attention to special features.
Note
indicates cross-references to other documents, e.g. operating manu-
als.
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 me-
dia 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 instru-
ment according to the instructions given in this operating manual is au-
thorized.
Any other use is considered to be unauthorized.

Safety Oxi 330i/340i
10
2.2 General safety instructions
This instrument is built and inspected according to the relevant guide-
lines 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 instru- ment can only be guaranteed if the generally applicable safety mea-
sures and the specific safety instructions in this operating manual are
followed during operation.
The smooth functioning and operational safety of the measuring instru-
ment 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
environment, the formation of condensate can lead to the faulty func-
tioning of the instrument. 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:
lhas been damaged in transport
lhas been stored under adverse conditions for a lengthy period of
time
lis visibly damaged
lno 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 fol- lowing laws and guidelines are observed when using dangerous sub-
stances:
lEEC directives for protective labor legislation
lNational protective labor legislation
lSafety regulations
lSafety datasheets of the chemical manufacturers.

Oxi 330i/340i Commissioning
11
3 Commissioning
3.1 Scope of delivery
lHandheld meter,Oxi330i or 340i
lPlug-in power supply, optional (340i only)
lOperating manual and short operating manual
l4 batteries, 1.5 V Mignon type AA (in the instrument)
3.2 Initial commissioning
Perform the following activities:
lSet the date and time
lConnect 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 ap-
pears 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
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 oxy-
gen measuring 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 instru-
ment.
2 Connect the original WTW plug-in power supply (3) to an easily
accessible mains socket.
2
1
3

Oxi 330i/340i Operation
13
4 Operation
4.1 Switching on the measuring instrument
Note
The measuring instrument has an energy saving feature to avoid un-
necessary battery depletion. The energy saving feature switches the
measuring instrument off if no key has been pressed for an hour. The
energy saving feature is not active when the AutoStore function is ac-
tive.
Measuring instrument
340i The energy saving feature is also not active
lif the power is supplied by the plug-in power supply,
lif the communication cable and a PC with a running communication
program are connected,
lif the recorder cable is connected,
lif 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
subsequently appears for approx. one second.
The measuring instrument then automatically switches to the
measuring mode that was last selected. The display shows the
relevant measured value.

Operation Oxi 330i/340i
14
4.2 Measuring
4.2.1 General information
You can measure the following variables:
lD. O. concentration
lD. O. saturation
lD. O. partial pressure
The measuring instrument is supplied with the following functions:
lAutoRange (automatic measurement range selection),
lThe AutoRead function (drift control) for checking the stability of the
measurement signal. This ensures the reproducibility of the measur-
ing 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 RS232
interface 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 mea-
suring instument. How to calibrate is described in section 4.3.
3Select the measuring mode with <M>.

Oxi 330i/340i Operation
15
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 de-
scribed in section 4.3.3 ENTERING THE SALT CONTENT (SALINITY).
Before measuring the oxygen, you have to switch on the salt content
correction (see below).
You can measure the oxygen content without a salt content correction
as follows:
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
content correction with <
 >. The SAL display indicator ap-
pears on the display. The value that was entered is taken into
consideration during 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
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 dis-
play indicator 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
appears 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
4.2.5 Selecting the measuring range, AutoRange
Sensors You can use the DurOx 325 or CellOx 325 sensors. If the automatic
recognition function recognizes the DurOx 325 sensor, the measure-
ment is carried out at a lower resolution. The CellOx 325 sensor mea-
sures with a resolution that is a factor of 10 higher.
AutoRange Each of the measuring parameters has 2 measuring ranges available.
AutoRange 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 sec-
tion 4.6 CONFIGURATION. When the AutoRange function is switched on,
ARng appears 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
4.2.6 AutoRead AR (drift control)
The AutoRead function (drift control) checks the stability of the mea-
surement signal. The stability has a considerable effect on the repro-
ducibility 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 mea-
sured 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/ENTER>.
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
4.3 Calibrating
Why calibrate? D. O. probes age. This changes the slope of the D. O. probe. Calibra-
tion determines the current slope of the probe and stores this value in
the instrument.
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 an-
other. The calibration of a specific sensor type does not affect the cali-
bration 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:
lCalibration in water vapor-saturated air.
To calibratethe CellOx 325, use the OxiCal®-SL aircalibration ves-
sel (accessory), to calibrate the DurOx 325, use the OxiCal®-D air
calibration vessel (contained in the scope of delivery of the sensor).
lCalibration via a comparison measurement (e. g. Winkler titration
according to DIN EN 25813 or ISO 5813). At the same time, the rel-
ative slope is adapted to the comparison measurement by a correc-
tion factor.
When to calibrate? lAfter connecting another D. O. probe
lIf the sensor symbol flashes, i. e. after the calibration interval has ex-
pired
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.
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
Printing the calibration
record (340i) The calibration protocol contains the calibration data of the current cal- ibration. You can transmit the calibration protocol to a printer via the se-
rial interface (see page 33).
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 calibrating. 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 display. The relative slope has no effect on the measuring accu-
racy. Low values indicate that the electrolytic filling will soon be deplet-
ed 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