Mettler Toledo InPro 6800 Instruction Manual

InPro 6800 Series O2Sensors

Instruction manual Bedienungsanleitung Instructions d’utilisation

InPro 6800 52 200 953

2 InPro 6800 Series O2Sensor 12/25 mm

InPro 6800 © 02 / 17 Mettler-Toledo GmbH 52 200 953 Printed in Switzerland

English Page 3

Deutsch Seite 36

Français Page 69

InDip, InFit, InPro, ISM, and InTrac are registered trademarks of the Mettler Toledo Group in Switzerland and a further twelve countries.

InPro 6800 Series O2Sensor 12/25 mm 3

InPro 6800 Series O2Sensors

Instruction manual

4 InPro 6800 Series O2Sensor 12/25 mm

InPro 6800 © 02 / 17 Mettler-Toledo GmbH 52 200 953 Printed in Switzerland

1 Introduction................................................................5

2 Important notes ..........................................................6

2.1 Notes on operating instructions .....................................6

2.2 Intended use ...............................................................6

2.3 Safety instructions........................................................7

2.4 Examples of some typical applications...........................8

2.5 Use in Ex-zones...........................................................8

2.6 Ex-classification ATEX ..................................................9

2.6.1 Introduction.................................................................9

2.6.2 Rated data..................................................................9

2.6.3 Special conditions......................................................10

2.7 Ex-classification FM approved.....................................11

3.1 General information....................................................12

3.2 Principle...................................................................12

3.3 Scope of delivery .......................................................12

3.4 Equipment features ....................................................13

4 Installation...............................................................15

4.1 Mounting the sensor...................................................15

4.2 Connection................................................................15

4.2.1 Connecting the InPro 6800 to a cable..........................15

4.2.2 Connecting the VP or AK9 cable to the transmitter..........16

5 Operation .................................................................17

5.1 Start-up and polarizing...............................................17

5.2 Calibration................................................................18

5.2.1 Purpose of calibration ................................................18

5.2.2 What you have to know for calibration .........................18

5.2.3 Single point calibration...............................................19

5.2.4 Dual point calibration.................................................20

6 Maintenance ............................................................21

6.1 Inspection of the sensor..............................................21

6.1.1 Visual inspection .......................................................21

6.1.2 Testing the sensor with the METTLER TOLEDO O

2

Sensor-Master InPro 6800..........................................22

6.1.3 Testing the sensor via a transmitter..............................23

6.2 Changing the electrolyte, the membrane body or

the interior body.........................................................24

7 Storage ....................................................................27

8 Product specification ................................................27

8.1 Certificates................................................................27

8.2 Specifications............................................................28

9 Ordering information.................................................29

9.1 Sensors....................................................................29

9.2 Accessories...............................................................29

9.3 Spare parts ...............................................................30

9.4 Recommended transmitters.........................................30

9.5 Recommended housings............................................30

10 Theory of the polarographic sensor............................31

10.1 Introduction...............................................................31

10.2 Principle of the design of an oxygen electrode...............32

10.3 Parameters determining current...................................32

10.4 Polarization voltage ...................................................33

10.5 Temperature..............................................................33

10.6 Dependence on flow...................................................34

10.7 Oxygen partial pressure – oxygen concentration............35

Contents

InPro 6800 Series O2Sensor 12/25 mm 5

1 Introduction

Thank you for buying the InPro®6800 sensor from METTLER TOLEDO.

The construction of the InPro 6800 sensors employs leading edge tech nology and complies with safety regulations currently in force. Notwithstanding this, improper use could lead to hazards for the user or a third-party, and/or adverse effects on the plant or other equipment. Therefore, the operating instruc-

tions must be read and understood by the persons involv ed before work is started with the sensor.

The instruction manual must always be stored close at hand, in a place accessible to all people working with the InPro 6800.

If you have questions, which are not or insufficiently answered in this instruction manual, please contact your METTLER TOLEDO supplier. They will be glad to assist you.

6 InPro 6800 Series O2Sensor 12/25 mm

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2 Important notes

2.1 Notes on operating instructions

These operating instructions contain all the information needed for safe and proper use of the InPro 6800 sensor. The operating instructions are intended for personnel entrusted with the operation and maintenance of the sensors. It is assumed that these persons are familiar with the equipment in which the sensor is installed.

Warning notices and symbols

This instruction manual identifies safety instructions and additional information by means of the following symbols:

This symbol draws attention to safety instructions and warnings of potential danger which, if neglected, could result in injury to persons and/or damage to property.

This symbol identifies additional information and instruc tions which, if neglected, could lead to defects, inefficient operation and possible loss of production.

2.2 Intended use

METTLER TOLEDO InPro 6800 sensors are intended solely for inline measurement of the oxygen partial pressure in liquids and gases, as described in this instruction manual. Any use of these sensors which differs from or exceeds the scope of use described in this instruction manual will be regarded as inappropriate and incompatible with the intended purpose.

The manufacturer/supplier accepts no responsibility whatsoever for any damage resulting from such improper use. The risk is borne entirely by the user/ operator.

Other prerequisites for appropriate use include:

– compliance with the instructions, notes and

requirements set out in this instruction manual.

– acceptance of responsibility for regular inspection,

maintenance and functional testing of all asso ci ated components, also including compliance with local operational and plant safety regulations.

– compliance with all information and warnings

given in the documentation relating to the products used in conjunction with the sensor (housings, transmitters, etc.).

– observance of all safety regulations governing the

equipment in which the sensor is installed.

InPro 6800 Series O2Sensor 12/25 mm 7

– correct equipment operation in conformance with

the prescribed environmental and operational conditions, and admissible installation positions.

– consultation with METTLER TOLEDO Process

Analytics in the event of any uncertainties.

2.3 Safety instructions

– The plant operator must be fully aware of the

potential risks and hazards attached to operation of the particular process or plant. The operator is responsible for correct training of the workforce, for signs and markings indicating sources of possible danger, and for the selection of appropriate, state-of-the-art instrumentation.

– It is essential that personnel involved in the

commissioning, operation or maintenance of these sensors or of any of the associated equipment (e.g. housings, transmitters, etc.) be properly trained in the process itself, as well as in the use and handling of the associated equipment. This includes having read and understood this instruction manual.

– The safety of personnel as well as of the plant itself

is ultimately the responsibility of the plant operator. This applies in particular in the case of plants operating in hazardous zones.

– The oxygen sensors and associated components

have no effect on the process itself and cannot influence it in the sense of any form of control system.

– Maintenance and service intervals and schedules

depend on the application conditions, composition of the sample media, plant equipment and signi ficance of the safety control features of the measuring system. Processes vary considerably, so that schedules, where such are specified, can only be regarded as tentative and must in any case be individually established and verified by the plant operator.

– Where specific safeguards such as locks, labels,

or redundant measuring systems are necessary, these must be provided by the plant operator.

– A defective sensor must neither be installed nor put

into service.

– Only maintenance work described in this operating

instruction may be performed on the sensors.

– When changing faulty components, use only

original spare parts obtainable from your METTLER TOLEDO supplier (see spare parts list, ”Section

9.3”).

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– No modifications to the sensors and the acces-

sories are allowed. The manufacturer accepts no responsibility for damages caused by unauthorised modifications. The risk is borne entirely by the user.

2.4 Examples of some typical applications

Below is a list of examples of typical fields of application for the oxygen sensors. This list is not exhaustive.

Measurement in liquids:

– Fermentation

– Yeast propagation

– Wort aeration

– Spring water conditioning

– Storage ans processing of fruit juices

Measurement in gases:

– Monitoring of the oxygen limit value to protect

products from oxidation.

– Monitoring of the oxygen limit value in the exhaust

air of fermentation vessels.

– Monitoring of oxygen limit values during inertiza-

tion processes.

– Measurement of oxygen concentrations in process

gas mixtures.

2.5 Use in Ex-zones

Attention!

For an installation in Ex-zones please read the guidelines following hereafter:

1258

Ex-classification ATEX:

Ex ia IIC T6/T5/T4/T3 Ga/Gb Ex ia IIIC T69°C/T81°C/T109°C/T161°C Da/Db

Number of the test certificate:

SEV 14 ATEX 0169 X IECEx SEV 14.0026X

Ex-classification FM approved:

IS / I, II, III /1/ABCDEFG / T6 Ta = 60 °C

- 53 800 002; Entity

InPro 6800 Series O2Sensor 12/25 mm 9

2.6 Ex-classification ATEX

2.6.1 Introduction

According to Directive 94/9/EC (ATEX 95) Appendix I, the O

2

oxygen sensors type InPro 6XXX is a devices of equipment group II, category 1/2G which, according to Directive 99/92/EC (ATEX 137) can be used in zones 0/1 or 1/2 or 1 or 2 as well as gas groups IIA, IIB and IIC, which are potentially explosive due to combustible substances in the temperature T3 to T6.

The requirements specified in EN 60079-14 must be observed during use / installation.

According to Directive 94/9/EC (ATEX 95) Appendix I, the O

2

oxygen sensors type InPro 6XXX is a devices of equipment group II, category 1/2D which, according to Directive 99/92/EC (ATEX 137) can be used in zones 20/21 or 21/22 or 21 or 22, which are potentially explosive due to combustible dust.

The requirements specified in EN 60079-14 must be observed during use / installation.

For the analog version of the O

2

oxygen electrode, the O2measurement circuit, temperature measurement circuit and data chip circuit are part of the common intrinsically safe system and are jointly connected to and operated by a separately certified transmitter.

The digital version of the O

2

oxygen sensor is connected to and operated by two-wire cable to the certified transmitter.

The intrinsically safe circuits are galvanically isolated from the non-intrinsically safe circuits up to a nominal voltage peak value of 375 V and from the earthed parts up to a nominal voltage peak value of 30 V.

2.6.2 Rated data

Analog O

2

Oxygen sensor

With type of protection: intrinsic safety to Ex ia IIC

O

2

measuring circuit, temperature measuring

circuit and data chip circuit

Only for connection to certified intrinsically safe circuits. Maximum values: Ui≤ 16 V, Ii≤ 190 mA, Pi≤ 200 mW Li= 0 (effective internal inductance) Ci= 900 pF (effective internal capacitance)

The values above apply, each as the sum of all the individual circuits of the associated intrinsically safe supply and evaluation unit (transmitter).

Digital O

2

Oxygen sensor

With type of protection: intrinsic safety to Ex ia IIC

10 InPro 6800 Series O2Sensor 12/25 mm

InPro 6800 © 02 / 17 Mettler-Toledo GmbH 52 200 953 Printed in Switzerland

Two-wire current circuit

Only for connection to certified intrinsically safe circuits. Maximum values: Ui≤ 16 V, Ii≤ 30 mA, Pi≤ 50 mW Li= negligible Ci= negligible

2.6.3 Special conditions

– The relationship between the maximum permissi-

ble ambient or media temperature and temperature class, for category 1G applications, zone 0, is shown in the following table:

Temperature class Max. ambient or

media temperature

T 6 68 °C T 5 80 °C T 4 108 °C T 3 160 °C

– The relationship between the maximum permissi-

ble ambient or media temperature and temperature class, for category 1D applications, zone 20, is shown in the following table:

Temperature class Max. ambient or

media temperature

T 69 °C 68 °C T 81 °C 80 °C T 109 °C 108 °C T 161 °C 160 °C

– The capacitance and inductance of the connecting

cable has to be considered.

– The O

2

Oxygen sensor type InPro 6XXX can be

used in / with the fittings InFit®76*-*** or InTrac

®

7**-***, or in / with other suitable fittings in potentially explosive areas.

– The metal body of the O

2

Oxygen sensors, or the

fittings InFit 76*-*** or InTrac 7**-***, or other appropriate fitting is optionally included in the routine pressure test of the system.

– The independent fitting used for installation of O

2

Oxygen sensor must be conductively connected to the equipotential bonding system.

InPro 6800 Series O2Sensor 12/25 mm 11

2.7 Ex-classification FM approved

A

B

C

D

E

F

E

D

C

B

A

1 2 3 4 5 6 7 8

Index

Title

Drawing No

METTLER TOLEDO

Process Analytics

CH-8902 Urdorf

Drawn F.Kogelmann 11-Dez-03 Scale 1:1

Change Dario Meier 25-Mai-16 Format DIN A3

Schutzvermerk ISO 16016 beachten / Refer to protection notice ISO 16016

Note - Replaces -

FM control drawing

53800002

E.4

Model: MODEL NAME

E.4

ArtikelNr: 53800002

Drawing: E.4 Rel.Level: Released Sheet: 1

/

1

R

Notes:

1. No revision to this drawing is permitted without FMRC approval.

2. Vmax > Vt; Imax > It; (Ci of all loops + C cable) < Ca; (Li of all loops + L cable) < La

Pmax or Pi > Po

3. Single Multi-Channel IS Barrier or Apparatus must be FMRC Approved.

4. Single Multi-Channel IS Barrier or Apparatus manufacturer`s control drawings

must be followed when installing the System. IS Barrier or Equipment may be

installed within the Hazardous (Classified) location for which it is approved.

5. Installation must be in accordance with Article 500 of the NEC (ANSI/NFPA 70) and

ANSI/ISA RP12.6.

WARNING: substitution of components may inpair intrinsic safety.

Entity Parameters:

Vmax (Ui)=16V, Imax (Ii)=50mA, Pi=0.25W

Ci=0.1 uF, Li=0 mH

Probe

Class I, Division 1, Groups A, B, C and D

Class II, Division 1, Groups E, F, and G

Class III, Division 1

T6 Ta=60 C

HAZARDOUS (CLASSIFIED) LOCATION

Any FMRC Approved Single

Multi-Channel Barrier or Apparatus

NONHAZARDOUS LOCATION

12 InPro 6800 Series O2Sensor 12/25 mm

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3 Product description

3.1 General information

The sensor InPro 6800 with integrated temperature probe is used for oxygen meas ure ment.

The sensor is sterilizable and autoclavable and compatible with CIP (cleaning in place).

InPro 6800 sensors with ISM®functionality offer Plug and Measure as well as enhanced diagnostics features. ISM sensors are available with K8S (fully digital) or VP connector.

3.2 Principle

Here is a short summary of the principle of pola rographic measurement on which this sensor is based (Clark 1961).

a) The Clark polarographic sensor basically consist

of a working electrode (cathode), a counter/reference electrode (anode), and an oxygen permeable mem brane which separates the electrodes from the sample medium.

b) The transmitter supplies a constant polarization

voltage to the cathode, needed to reduce oxygen.

c) The oxygen molecules which migrate through the

permeable membrane are reduced at the cathode. At the same time, oxidation takes place at the anode and oxidized anode metal (silver) is libe rated as silver ions into the electrolyte. The electro lyte closes the electric circuit between anode and cathode (ion conductivity).

d) The current produced by the reactions described

above is measured by the transmitter and is proportional to the partial pressure of oxygen (pO

2

) in the sample medium.

Please refer to Section 10 ”Theory of the polarogra phic sensor” for further information.

3.3 Scope of delivery

Each sensor is supplied fully assembled and factorytested for correct function together with:

– a quality control certificate – inspection certificates 3.1B

(complying with EN 10204.3/1B)

See electrolyte order details at section „Spare Parts“,

9.3.

InPro 6800 Series O2Sensor 12/25 mm 13

3.4 Equipment features

12 mm Sensor

VP connector (straight version) (K8S connector for digital ISM)

O-ring

(10.77x2.62 mm, Silicone FDA)

Interior body

Anode (solid silver)

Cathode Retainer nut

O-ring

(Silicone FDA/USP VI)

Cap sleeve (N-type)

Protection cap

Washer

Pg 13.5 threaded sleeve

O-ring

(9.0x1.0 mm, Silicone FDA/USP VI)

Membrane body

14 InPro 6800 Series O2Sensor 12/25 mm

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Cap nut G1" O-ring

(20.29 x2.62 mm, Silicone FDA/ USP VI)

Interior body

Anode (solid silver)

Cathode Retainer nut

Membrane body

Cap sleeve (N-type)

Protection cap

25 mm Sensor

O-ring

(9.0x1.0 mm, Silicone FDA/ USP VI)

O-ring

(Silicone FDA/USP VI)

VP connector (angled version) (K8S connector for digital ISM)

InPro 6800 Series O2Sensor 12/25 mm 15

4 Installation

4.1 Mounting the sensor

Important! Remove the green protective cap before

mount ing the sensor.

Mounting the sensor in a housing

Please refer to the instruction manual of your housing explaining on how to mount the sensor in place.

Mounting the sensor directly on a pipe or a vessel

The sensor can be mounted vertically or in an inclined position. In the case of inclined mounting, the angle of the housing must be equal to or greater than 15° above the horizontal.

Caution! Installation outside the admissible range of mounting positions is not allowed, otherwise correct operation of the sensors / electrodes may be impaired.

52910536

admissible mounting positions

zulässige Einbaulagen

positionements de montage admis

admissible mounting position

zulässige Einbaulage

positionement de montage admis

inadmissible (except for optical sensors)

unzulässig (ausser für optische Sensoren)

ne pas admissible (sauf pour sondes optiques)

The 12 mm sensors can be mounted directly through a socket with inside thread Pg 13.5 and securely tightened via the Pg 13.5 threaded sleeve.

The 25 mm sensors can be mounted directly through a standard weld-in socket or the safety weld-in sockket from METTLER TOLEDO.

4.2 Connection

4.2.1 Connecting the InPro 6800 to a cable

Sensors with ISM functionality require the use of a special AK9 cable as well as an ISM compatible O

2

trans-

16 InPro 6800 Series O2Sensor 12/25 mm

InPro 6800 © 02 / 17 Mettler-Toledo GmbH 52 200 953 Printed in Switzerland

4.2.2 Connecting the VP or AK9 cable to the transmitter

Note: Cable assignment can be found in the METTLER

TOLEDO VP or AK9 cable instruction manual.

Note: For connecting the cable to the terminals of the transmitter, please refer to the instructions given in the METTLER TOLEDO transmitter manual.

VP or AK9 cable

O

2

transmitter

VP-6 cable for standard use AK9 cable for ISM functionality

Plug

Slit

VP connector K8S connector for digital ISM

mitter. The sensor is connected to the transmitter via a AK9 cable. The AK9 cable ensures a secure connection between the transmitter and the sensor under harsh industrial conditions. The robust watertight IP68 connector housing guarantees maximum process safety. If you have chosen to use a sensor with digital ISM functionality, the K8S connector will incorporate a preamplifier. It is absolutely necessary to protect this electronic component against any electrical charge.

Do not touch the sensor at the VP connector plug.

To connect the VP cable to the sensor align the slit of the VP connector with the pin in the plug. Then tightly screw the plug to fasten the two parts.

InPro 6800 Series O2Sensor 12/25 mm 17

5 Operation

Attention! Before using the sensors for the first time,

the electrolyte should be replaced (see ”Chapter 6.2”). Due to possible adverse conditions during transport and storage (e.g. airfreight; pressure and temperature variations), the quality of the electrolyte may become impaired. Poor electrolyte quality can lead to erroneous measurement values.

5.1 Start-up and polarizing

Attention! The protective cap at the tip of the sensor

must be removed before putting the sensor into ope ration.

When the system is operated for the first time or if the sensor has been disconnected from the voltage source (transmitter or O

2

Sensor-Master) for longer than 5 min utes, the sensor has to be polarized prior to calibration by connecting it to the operating O2transmitter or to a sensor master. After 6 hours, the sensor is fully polarized and ready for operation. A shorter polarization period is sufficient if the sensor has been disconnected for only a few minutes. The following table serves to establish the correct polari zation time in relation to the depolarization time.

Depolarization time1 Minimum required t

depol

[Min.] polarization time2[Min.]

t

depol

> 30 360

30 > t

depol

> 15 6 * t

depol

15 > t

depol

> 5 4 * t

depol

t

depol

< 5 2 * t

depol

1 Depolarization time:

Time span in which the polarization voltage is cut off from the sensor. This is the case during: – change of electrolyte – change of membrane body – the time the cable is disconnected or no transmitter

or sensor master is connected to the cable

2 Polarization time:

Time span during which the sensor is under a polari zation voltage.

Attention! Setting of the polarization voltage on the transmitter for correct measurements:

– Standard applications (e.g. measurement in

bio tech nology): – 675 mV

– Measurement of permanently low oxygen concen-

trations <500 ppb in the presence of volatile acidic components (e.g. carbon dioxide during measurements in breweries): – 500 mV

Important! To ensure the supply of the correct polariza tion voltage the transmitter must be set accordingly.

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5.2 Calibration

5.2.1 Purpose of calibration

Each oxygen sensor has its own individual slope and own individual zero point. Both values are subject to change, for example, through electrolyte consumption or after exchange of electrolyte or membrane body. To ensure high measurement accuracy of the sensor, a calibration must be carried out after each change of electrolyte or membrane. Prior to calibration, the sensor has to be polarized for at least 6 hours.

A zero point calibration is only advisable if very high accuracy is required at low oxygen concentrations.

To check if your sensor needs a recalibration, you may dry it and take it in the air to check that the reading is close to 100%. If not, then the sensor needs a new calibration.

5.2.2 What you have to know for calibration

Attention! If dissolved oxygen is being measured at

low concentrations (<500 ppb) in the presence of volatile acidic components (e.g. carbon dioxide (CO

2

) measurements in breweries), the calibration procedure described below should be followed in order to achieve the best measurement performance.

No special calibration procedure is required if dissolved oxygen is being measured in standard applications (e.g. measurement in biotechnology).

First step: Adjust the transmitter polarization voltage to – 675 mV. Detailed information is given in the transmitter instruction manual.

Second step: After adjusting the polarization voltage to – 675 mV, equilibration time is required. Wait for about 5 minutes before carrying out step 3.

Third step: Perform calibration according to the transmitter’s instruction manual.

Fourth step: Adjust the transmitter polarization voltage back to –500 mV.

Where is oxygen being measured?

Standard applications

(e.g. measurement in

biotechnology).

No special procedure required.

Refer to transmitter instruction

manual and general remarks below.

Follow step 1 to step 4

and general remarks

below.

Measurement of permanently low oxygen

concentrations (<500ppb) in the pre-

sence of volatile acidic components

(e.g. CO

2

at measurements in breweries).

InPro 6800 Series O2Sensor 12/25 mm 19

General remarks:

– For calibration in air, the sensor membrane must

be dry, since adhering water drops can falsify the

measured oxygen value.

– Make sure that the oxygen saturation index of the

calibration medium is correct and remains constant during calibration.

– In the event of calibration in water or sample

medium, the calibration medium must be in equilibrium with the air. Oxygen exchange between water and air is only very slow. Therefore it takes quite long time until water is saturated with atmospheric oxygen.

– For correct calibration, a minimum flow rate of the

calibration medium is necessary.

– Calibration in a fermenter should be performed

after sterilization (as sterilization may alter the sensor slope), but prior to innoculation. If it is not possible to perform the calibration after sterilization, the use of an existing membrane body that has been pre-sterilized while mounted in the sensor is recommended. A slope alteration of some per cent can occur with new membrane bodies, particularly after a first sterilization, as the tension of the membrane may be altered by the sterilization process.

– Make sure that all other parameters, such as

temperature and pressure, are constant.

For continuous applications, we recommend periodic

recalibration in line with your requirements on accuracy, the type of process in operation and your own experience. The frequency of the need for re-

calibration depends very much on the specific application, and therefore appropriate intervals cannot be exactly defined here.

5.2.3 Single point calibration

By carrying out a single point calibration, the factual slope of the sensor can be established. The calibration medium can be water with known oxygen saturation index (e.g. air-saturated water) or air with known water-vapor saturation (e.g. water-vapor saturated air).

After the sensor signal has stabilized, the complete meas uring system can then be calibrated to the 100 % value of the desired measurable variable, e.g.100 %

Steps 1 to 4 can be accomplished automatically if you use the M 700 transmitter. Thus the routine can be minimized to a few keystrokes. In addition the M 700 transmitter must be equipped with the software function SW-700-011 ”high CO

2

compensation”. Please ask

your local METTLER TOLEDO distributor.

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air, 20.95 % O2, or 8.26 ppm at 25 °C (77 °F) and normal pressure (see instruction manual for the trans mitter).

Single point calibration should be sufficient for almost all process applications.

5.2.4 Dual point calibration

By carrying out a dual point calibration both slope and zero point of the sensor can be established.

Important! In case of a dual point calibration, always start by the zero point calibration before calibrating

the slope.

Due to the very low zero current of METTLER TOLEDO sensors, dual point calibration is normally not necessary for standard applications. As a rule, the zero point should be adjusted to zero manually, or it is automatically performed by the transmitter (see instruction manual for the transmitter). A zero point calibration is only advisable if very high accuracy is required at low oxygen concentrations.

Attention! Incorrect zero point calibration is a frequent source of measurement error. For correct calibration, we recommend the use of nitrogen gas or other oxygen-free medium with a level of purity of at least 99.995%.

After the sensor signal has stabilized (after 20…30 minutes), the sensor can be calibrated through the relevant transmitter to the 100 % value of the desired measurable variable, e.g. 0 % air, 0.0 % O

2

, or

0.0 ppm (see instruction manual for the transmitter).

InPro 6800 Series O2Sensor 12/25 mm 21

6 Maintenance

6.1 Inspection of the sensor

6.1.1 Visual inspection

To check your sensor, we recommend the following procedure:

• The contacts of the connector must be dry.

Moisture, corrosion and dirt in the connector can lead to false readings.

• Check the cable for buckling, brittle areas or

ruptures.

• Before calibration always examine the membrane

foil optically for signs of damage. The foil must be intact and clean. Dirty membranes should be wip ed clean using a soft, moist tissue. Note: An undulated membrane has no influence on the sensor performance, assuming the membrane is intact.

• The membrane body must be replaced if the sensor

has too long a response time, the reading is unstable or subject to drift, and if the sensor cannot be calibrated or the membrane shows sign of mechanical damage.

• Check the cathode area for discoloration, conta -

mination or cracks in the glass. If necessary rinse with demineralized water and clean with a clean soft brush or soft paper tissue.

Attention! Do not use any cleaning agents con taining alcohol. This could damage the sensor or lead to fault current.

Attention! The glass body is fragile and sensitive to vibration.

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6.1.2 Testing the sensor with the METTLER TOLEDO O2Sensor-Master InPro 6800

We recommend to use the METTLER TOLEDO O

2

Sensor-Master InPro 6800 to check the quality of your sensor as follows (not applicable for digital ISM sensors):

• Connect the sensor to the O2Sensor-Master.

LED

Switch

As soon as the sensor is connected to the O

2

Sensor-Master, the polarization function is automatically activated. Please note: if the sensor was disconnected from the transmitter for longer than 5 minutes, the sensor must be polarized first (polarizing time see section 5.1) to get representative test results.

• Battery Check:

Push the switch to the left. If the battery is ok and the O

2

Sensor-Master is operational the green LED lights up. Otherwise, please consult the instruction manual of the O2Sensor-Master.

• Sensor Check: For this test the O2sensor must be fully polarized and the membrane of the sensor must be dry and

clean.

Expose the sensor (connected to O

2

Sensor Master) to the air. By pushing the switch to the right to the position ”2 – Sensor check”, the O2SensorMaster checks wether the electrode current for air measurement delivered by the sensor is within the admissible range (40 to 100 nA for InPro 6800). If the green LED lights up the current for air measurement is with in the admissible range.

METTLER TOLEDO

O

2

Sensor-Master

InPro 6800

Order No. 52 200 892

The polarization function

will be activated automatically

,

when a sensor is connected.

After the sensor polarization

you should check the functions

of the sensor as following:

1. Battery Check

2. Sensor Check Green light = ok

left

Battery Check

middle

Autom. Polariz.

right

Sensor Check

1

2

InPro 6800 Series O2Sensor 12/25 mm 23

If the LED does not light up, you should check the battery of the O2Sensor-Master (see instruction manual ”Accessories”). If the battery is working, than there is probably a problem with your sensor. You should change the electrolyte and/or the membrane body of your sensor. If after a membrane change the LED still does not light up, this means that there is maybe something wrong with the interior body of the sensor. You should than change it (see ”Section 6.2”).

Important! The sensor check function only veryfies the correctness of the electrode current for air measurement. In order to be absolutely sure of the functionality of the sensor, the residual signal in an oxygen free medium should also be controlled (see ”Section 6.1.3”).

6.1.3 Testing the sensor via a transmitter

A periodic zero current measurement (no zero point calibration) is recommended for verification of proper

sensor function.

At the time you carry out the zero current measurement, the sensor must be polarized.

Zero current measurement can be done by using zero ing gel (order no. 30 300 435) or nitrogen (N

2

) or carbon dioxide (CO2) calibration gases with a purity of at least 99.995 %, alternatively in a sample medium saturated with one of these gases. After 2 minutes in an oxygen-free sample medium, the reading on the transmitter should drop to below 10 % of the reading in ambient air, and within 10 minutes the value should have dropped to below 1 %.

If the measured values are too high, this suggests a depleted electrolyte or a defective membrane. In the first instance replace the electrolyte, and in the second case exchange both the membrane body and the electrolyte accordingly.

If after such procedures the above mentioned values are still not reached, replace the interior body. If this doesn't solve the problem too send the sensor to your local METTLER TOLEDO representative for inspection.

Many sample media contain volatile substances which, even at very low concentrations, have a clearly perceptible smell. Similarly to oxygen, these sub-stances are able to invade the electrolyte through the gas-permeable membrane. Accordingly, they become noticeable when changing the electrolyte. In most cases, such substances have absolutely no influence on the measuring properties of the sensor. Slight discoloration of the electrolyte also has no effect on the measuring properties.

24 InPro 6800 Series O2Sensor 12/25 mm

6.2 Changing the electrolyte, the membrane body or the interior body

METTLER TOLEDO DO sensors are supplied with fitted membrane body and have been checked for proper function.

However, if a sensor is to be stored for several months, the electrolyte should be replaced before use.

If the membrane exhibits signs of failure (long response time, increased current in an oxygen-free medium, mechanical damage, etc.) the membrane body has to be replaced.

Warning! The O

2

electrolyte has an alkaline pH value of 13. Contact of electrolyte with mucous membrane or eyes is to be avoided. Therefore protective gloves

and safety glasses have to be worn for the following dismantling works.

If such contact occurs, the affected area should be well rinsed with water. In the case of accident, or should ever any adverse signs appear, get immediate medical attention.

When changing the electrolyte, the membrane body or the interior body, please observe the following instructions (see also the following illustration):

Attention! Make sure that this maintenance step is carried out in clean place.

1. Unscrew the cap sleeve from the sensor shaft and

carefully pull it off the sensor.

2. Pull off the membrane body from the interior body.

If it is tight-fitted, eject by pushing it with the flat finger tip. Before electrolyte is refilled, the membrane body must be removed from the cap sleeve.

3. Rinse the interior body with demineralized water

and carefully dab it dry with a paper tissue.

Note: steps 4 to 7 may only be carried out when changing the interior body.

4. Unscrew the retainer nut of the interior body with

an adjustable wrench or with a 3/8" wrench.

5. Remove the interior body by pulling it out of the

sensor shaft. If necessary use a plier. Warning! Do not twist the interior body. Otherwise the connection pins can be damaged.

InPro 6800 Series O2Sensor 12/25 mm 25

6. Insert the new interior body in the sensor shaft.

Turn the interior body in the shaft until the slit of the interior body is aligned with the pin placed in the shaft.

7. Press the body in the shaft and screw the new

retainer nut in place.

8. Examine the O-rings visually for mechanical

defects, and replace if necessary.

9. Half-fill the new membrane body with O

2

electrolyte and make sure that all bubbles are removed. Air bubbles can be removed by care fully tapping on the membrane body.

10. Slip the membrane body over the interior body

while holding the sensor in a vertical position. The excess electrolyte will be displaced and have to be removed with a paper tissue. Attention! No electrolyte, sample media or contamination may be present between the membrane body and the cap sleeve. Please check carefully.

11. Carefully slip the cap sleeve over the fitted

membrane body, holding the sensor in a vertical position and screw it tight. The cap sleeve must be clean and dry.

12. After each exchange of electrolyte or membrane

body, the sensor has to be repolarized and re calibrated.

1

/

2

1

/

2

O2electrolyte

26 InPro 6800 Series O2Sensor 12/25 mm

3/8"

Slit

O-ring

9.0x1.0 mm, Silicone FDA/USP VI

O-ring

20.29x2.62 mm,

Silicone FDA/USP VI

O-ring

10.77x2.62 mm, Silicone FDA/USP VI

O-rings

Interior body

Retainer nut

(O-ring inside)

Membrane body

Cap sleeve (N-type)

O-ring

Silicone FDA/USP VI

InPro 6800 Series O2Sensor 12/25 mm 27

7 Storage

The sensor can be stored for several months filled with O2electrolyte (order no. 30 298 424) as long as the protective cap is in place. In order to avoid the 6-hour polarization time before reuse of the sensor, it can be kept stored connected to the METTLER TOLEDO O

2

Sensor-Master InPro 6800.

Attention! The electrolyte should be replaced before use if the storage period exceeds 3 months.

If the storage period exceeds 6 months, the sensor should be stored dry, i.e. without any electrolyte in the membrane body.

Attention! A sensor being stored dry (without electrolyte in the membrane body) may on no account

be connected to the O2Sensor-Master InPro 6800.

8 Product specification

8.1 Certificates

Each sensor is delivered with a set of 3.1 B certificates (complying with EN 10204.3/1.B).

All wetted metal parts (sensor shaft, cap sleeve and membrane body) are identified with a engraved symbol corresponding to the heat number on the paper certificate delivered with the sensor.

Each wetted metal part (sensor shaft, cap sleeve and membrane body) is polished in order to get a surface roughness lower than 0.4µm (16µin). This represents a roughness grade number of N5 (according to ISO 1320:1992).

28 InPro 6800 Series O2Sensor 12/25 mm

8.2 Specifications

Attention! Please refer to the supplementary sheet

52 201 146 if the sensor, together with the membrane body T-6800 gas, is been used for measurement of oxygen partial pressure in gases. This supplementary sheet is only included in the packaging of T-6800 gas membrane bodies and kits.

InPro 6800

Measurement principle Amperometric/Polarographic

Working conditions

Pressure resistance measurement 0.2 – 6 bar absolute

[2.9 – 87.0 psi absolute]

Mechanical pressure resistance max. 12 bar absolute

[174.0 psi absolute] Measuring temperature range 0…80°C [32…176°F] Temperature range – 5…140 °C [23…284°F]

(sterilizable/autoclavable)

Construction

Temperature compensation Automatic with built-in RTD Cable connection VarioPin (IP68) straight or angled

K8S straight (digital ISM sensors) O-ring material Silicone FDA and

USP VI approved Membrane material PTFE/ Silicone/ PTFE

(reinforced with steel mesh) Wetted metal parts Stainless steel

Special material on request Surface roughness of N5 (R

a

< 0.4 µm [16µin])

wetted metal parts (ISO 1320:1992) Quick disconnect interior body Standard Cathode Pt Anode Ag Guard ring No

Dimensions

Sensor diameter 12 or 25 mm (0.47" or 0.98") Immersion length (a) for 12mm sensor 70, 120, 220, 320, 420 mm

(2.8, 4.7, 8.66, 12.6, 16.54") Immersion length (a) for 25mm sensor 80,160, 260, 360 mm

(3.15, 6.3, 10.24, 14.17")

Performances

Detection limit 6 ppb Accuracy ≤ ±[1% + 6 ppb]

of reading in liquids Response time at 25°C / 77 °F (air ➝ N2) 98 % of final value <90 s Sensor signal in ambient air (25 °C /77°F) 50…110 nA Residual signal in oxygen-free medium <0.1 %

of the signal in ambient air Maximum flow error ≤5%

Certification

EHEDG, 3A Yes

3.1 B (EN 10204.3/1.B) Yes ATEX certificate Yes FM Approval Yes FDA / USP VI Yes Quality control Yes

Compatibility

with METTLER TOLEDO transmitters see ”Section 9.4” with METTLER TOLEDO housings see ”Section 9.5”

InPro 6800 Series O2Sensor 12/25 mm 29

9 Ordering information

For more detailed information refer to the technical data sheet. Ask your local distributor.

9.1 Sensors

Sensor without ISM functionality

Immersion 12 mm diameter 25 mm diameter length (a) straight angled straight angled

70 mm (2.8") 52 200 964 52 200 969 –– –– 80 mm (3.2") –– –– 52 200 974 52 200 978 120 mm (4.7") 52 200 965 52 200 970 –– –– 160 mm (6.3") –– –– 52 200 975 52 200 979 220 mm (8.7") 52 200 966 52 200 971 –– –– 260 mm (10.2") –– –– 52 200 976 52 200 980 320 mm (12.6") 52 200 967 52 200 972 –– –– 360 mm (14.2") –– –– 52 200 977 52 200 981 420 mm (16.5") 52 200 968 52 200 973 –– ––

9.2 Accessories

Accessories Order no.

O2Sensor-Master InPro 6800 52 200 892 O2Sensor-Simulator 52 200 891 Adapter T82 socket – VP plug 52 200 939 Adapter VP socket – T82 plug 52 200 940 VP cable VP6-ST/3 m 52 300 108 VP cable VP6-ST/5 m 52 300 109 VP cable VP6-HT/3 m 52 300 112 VP cable VP6-HT/5 m 52 300 113 VP cable VP8-ST/3 m 52 300 354 VP cable VP8-ST/5 m 52 300 355 VP cable VP8-HT/3 m 52 300 361 VP cable VP8-HT/5 m 52 300 362 Oxygen zeroing gel (3× 25 ml) 30 300 435

For other cable lengths or types, please contact your local METTLER TOLEDO representative.

Intelligent Sensor Management (ISM) O2sensor configuration

InPro 6 _ _ _ / _ _ / _ _ _ / _ _ _

Blank: Standard functionality ISM: Intelligent Sensor Management

Immersion length (a) in mm

For diameter/immersion lengths combinations, please see table below:

(a) InPro 68xx

[ 12 [ 25

070 ✓ – 080 – ✓

120 ✓ – 160 ✓✓ 220 ✓ – 260 – ✓

320 ✓ – 360 – ✓ 420 ✓ –

Sensor diameter: 12 = 12 mm; 25 = 25 mm

00: VP Plug head, straight

10: VP Plug head, angled

8: InPro 68xx

Example configuration:

InPro 6800/12/120/ISM ➝ Sensor with ISM functionality

InPro 6810/25/260 ➝ Sensor without ISM functionality

30 InPro 6800 Series O2Sensor 12/25 mm

9.3 Spare parts

Spare parts Order no.

Membrane body, single T-96 52 200 071 Membrane kit T-96 52 200 024

(4 membrane bodies, 1 O-ring set, 25 ml Electrolyte bottle)

Membrane bodies (20 pcs.) T-96 52 200 791 O2Electrolyte pack (3× 25 ml) 30 298 424 Interior body InPro 6800 52 200 899

(with quick disconnect) Cap sleeve N-type 52 200 037 Cap sleeve with protective cage P-type 52 200 038

9.4 Recommended transmitter

Note: Ask your local distributor or refer to the techni-

cal data sheet.

9.5 Recommended housings

Housings 12 mm Ø 25 mm Ø

Static housings

INGOLD ”safety weld-in socket” – 3

InFit 761 CIP 3 –

Retractable housings

InFit 777 e 3 – InFit 797 e 3 –

Immersion housing

InDip

®

550 3 –

Note: The housings are available in different versions. Please contact your distributor to get the right odering information.

Please ask your local METTLER TOLEDO representative.

Mettler Toledo InPro 6800 Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual