wtw SensoLyt 690 User manual

ba15312e03 07/2015
SensoLyt®690
Operating manual
pH/ORP armature with impedance
converter and temperature sensor

26
SensoLyt®690
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.
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.
Note
The latest version of the present operating manual can be found on the
Internet under www.WTW.com.
Copyright ©Weilheim 2006, WTW GmbH
Reprinting - even as excerpts - is only allowed with the explicit written
authorization of WTW GmbH, Weilheim.
Printed in Germany.

SensoLyt®690 Contents
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SensoLyt®690 - Contents
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
1.1 Structure of the SensoLyt®690 pH/ORP armature . . . . 28
1.2 Recommended fields of application . . . . . . . . . . . . . . . . 28
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.1 General information on safety . . . . . . . . . . . . . . . . . . . . 29
2.2 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.3 User qualifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.4 General safety instructions . . . . . . . . . . . . . . . . . . . . . . . 30
3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.1 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3 Commissioning / Getting the instrument ready for measuring
33
4 Measuring / Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.1 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.2 Measuring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
5 Maintenance and changing the electrode . . . . . . . . . . 37
5.1 General maintenance instructions . . . . . . . . . . . . . . . . . 37
5.2 Replacing the combination electrode . . . . . . . . . . . . . . . 37
5.3 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
5.4 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6 Replacement parts and accessories . . . . . . . . . . . . . . 42
6.1 Combination electrodes . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.2 General accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
7 What to do if... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
8 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
8.1 Measurement characteristics . . . . . . . . . . . . . . . . . . . . . 44
8.2 Application characteristics . . . . . . . . . . . . . . . . . . . . . . . 44
8.3 General data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
8.4 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Overview SensoLyt®690
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1 Overview
1.1 Structure of the SensoLyt®690 pH/ORP armature
Fig. 1-1 Structure of the SensoLyt®690 pH/ORP armature
Note
The pH combination electrodes that can be used are available as
accessories (see chapter 6 REPLACEMENT PARTS AND ACCESSORIES).
Impedance converter An impedance converter integrated in the armature shaft converts the
high-impedance measurement signal of the electrode into a low-
impedance signal. This ensures an interference-free signal
transmission even over greater distances.
1.2 Recommended fields of application
In conjunction with the SensoLytSEA(-HP), SensoLytDWA and
SensoLytECA pH combination electrodes as well as the
SensoLytPtA ORP combination electrode, the SensoLyt®690 pH/
ORP armature is suitable for stationary measurements in water and
wastewater applications.
1Protective hood
2Temperature sensor
3Electrode (not contained in the scope of delivery)
4Electrode receptacle
5Armature shaft
12345

SensoLyt®690 Safety
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2 Safety
2.1 General information on safety
These safety instructions contain all instructions that have to be
followed for a safe operation of the SensoLyt®690 pH/ORP armature.
Before starting any work with the SensoLyt®690, carefully read the
safety instructions and strictly follow all protective measures
mentioned.
Always keep this operating manual in the vicinity of the armature.
General safety
instructions
Safety instructions in this operating manual can be recognized by the
warning symbol (triangle) in the left column. The signal word (e. g.
"Caution") indicates the level of the danger:
Warning
indicates instructions that must be followed precisely in order to
prevent serious dangers to persons.
Caution
indicates instructions that must be followed precisely in order to
avoid slight injuries or damage to the instrument or the
environment.
Other labels
Note
indicates notes that draw your attention to special features.
Note
indicates cross-references to other documents, e.g. operating
manuals.

Safety SensoLyt®690
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2.2 Authorized use
The authorized use of the SensoLyt®690 consists of the stationary
measurement of pH or ORP and temperature in conjunction with a pH
or ORP combination electrode. The technical specifications according
to chapter 8 TECHNICAL DATA must be observed. Only operation
according to the instructions given in this operating manual is
considered to be authorized.
Any other use is considered to be unauthorized. Unauthorized use
invalidates any claims with regard to the guarantee.
2.3 User qualifications
Calibrating the SensoLyt®690 requires the handling of chemicals.
Thus, we assume that the relevant personnel are familiar with the
necessary precautions to take when dealing with chemicals as a result
of their professional training and experience.
2.4 General safety instructions
Function and
operational safety
The armature left the factory in a safe and secure technical condition.
The failure-free function and operational safety of the armature is only
guaranteed if the generally applicable safety measures and the special
safety instructions in this operating manual are followed during its use.
The smooth functioning and operational safety of the armature can only
be guaranteed under the environmental conditions that are specified in
chapter 8 TECHNICAL DATA.
The specified temperature (chapter 8 TECHNICAL DATA) must be
maintained during the application and transport of the armature.
Protect the armature, particularly against frost or overheating.

SensoLyt®690 Safety
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Safe operation If safe operation is no longer possible, the armature must be taken out
of operation and secured against inadvertent operation.
Safe operation is no longer possible if the armature:
has been damaged in transport
has been stored under adverse conditions for a lengthy period of
time
is visibly damaged
no longer operates as described in this manual.
If you are in any doubt, contact the supplier of your armature.
Obligations of the
operator
The operator of the armature must ensure that the following rules and
regulations are followed when dealing with hazardous substances:
EEC directives for protective labor legislation
National protective labor legislation
Safety regulations
Safety data sheets of the chemical manufacturer.
Caution
All changes of the SensoLyt®690 that exceed the work described
in this operating manual are not allowed. Repair work may only be
carried out by WTW Weilheim.

Commissioning SensoLyt®690
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3 Commissioning
3.1 Scope of delivery
SensoLyt®690 pH/ORP armature
The armature is equipped with a protective hood and protection
caps
Operating manual.
3.2 Installation
Caution
The SensoLyt®690 pH/ORP armature may only be submersed in
conjunction with a mounted combination electrode. When
exchanging the electrode, no moisture may get into the armature,
as otherwise the armature will be destroyed. Which electrodes
can be used together with the SensoLyt®690 pH/ORP armature is
given in section 6.1 COMBINATION ELECTRODES.
Connection to the
measuring transmitter
The connection cable of the SensoLyt®690 is ready to be connected
to the terminal strip of a measuring transmitter with high-impedance
pH/ORP input. For all further information please refer to the operating
manual of the measuring transmitter. The assignment of the cable
wires of the SensoLyt®690 can be found in the chapter 8 TECHNICAL
DATA of this operating manual.
Note
Do not suspend the sensor on the sensor connection cable. Use an
armature or electrode holder. Information on this and other
accessories is given in the WTW catalog and on the Internet.

SensoLyt®690 Commissioning
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3.3 Commissioning / Getting the instrument ready for
measuring
Note
A KCI-filled plastic cap is mounted on the tip of the sensor to keep the
electrode active during storage (or during longer pauses in measuring).
The cap must be removed for measuring.
Mounting the
combination electrode 1Unscrew the protective hood from the armature.
2Pull off the blind plug from the plug head socket of the
armature.
3Screw off the protective cap of the plug head connector of the
electrode.

Commissioning SensoLyt®690
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Caution
Push the connected electrode into the armature right up to the
stop so that the connection is watertight.
4Screw the electrode into the plug head socket of the armature.
5Push the unit into the armature up to the stop.
6Pull the KCI-filled plastic cap off the electrode for measuring.

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7Screw the protective hood onto the armature.
8Make the settings for the electrode on the measuring
transmitter. Subsequently, calibrate the measuring system
(see section 4.1 CALIBRATION).

Measuring / Operation SensoLyt®690
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4 Measuring / Operation
Note
Calibrate the measuring system after the initial commissioning and at
regular intervals (depending on the application).
4.1 Calibration
Why calibrate? During the operation of a pH electrode, the slope and asymmetry of the
electrode changes with time. The calibration procedure determines the
current slope and asymmetry of the electrode.
When to calibrate? Calibrate before measuring and at regular intervals (depending on the
application).
Calibration procedures The available calibration procedures depend on the measuring
transmitter used. The individual steps for the calibration are
comprehensively described in the operating manual of the measuring
transmitter.
4.2 Measuring
Warning
Contact with the sample can lead to danger to the user!
Depending on the type of sample, suitable protective measures
must be taken (protective clothing, protective goggles, etc.).
Please pay attention to:
the minimum immersion depth of the armature (> 40 mm)
the measuring range of the electrode used (see operating manual of
the electrode).

SensoLyt®690 Maintenance and changing the electrode
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5 Maintenance and changing the electrode
5.1 General maintenance instructions
The SensoLyt®690 pH/ORP armature works maintenance-free.
Please read the maintenance of the electrode in the relevant operating
manual of the electrode.
5.2 Replacing the combination electrode
Warning
Contact with the sample can lead to danger to the user!
Depending on the type of sample, suitable protective measures
must be taken (protective clothing, protective goggles, etc.).
Caution
If the glass of the pH electrode breaks, there is a danger of cuts
from the splinters of glass!
If it is necessary to replace an electrode, proceed as follows:
1Unscrew the protective hood from the armature.

Maintenance and changing the electrode SensoLyt®690
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2Use the protective hood as a tool to lever out the electrode.
3Carefully pull out the electrode until the plug head screwed
fitting can be seen.
4Unscrew the combination electrode from the plug head socket
(for disposal, see section 5.4).

SensoLyt®690 Maintenance and changing the electrode
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Caution
Push the connected electrode into the armature right up to the
stop so that the connection is watertight.
5Screw in a new electrode.
6Push the unit into the armature up to the stop.
7Pull the KCI-filled plastic cap off the electrode for measuring.
8Screw the protective hood onto the armature.

Maintenance and changing the electrode SensoLyt®690
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9Calibrate the measuring system (see section 4.1 CALIBRATION).

SensoLyt®690 Maintenance and changing the electrode
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5.3 Cleaning
For normal operation (e.g. municipal wastewater), exterior cleaning
and calibration are strongly recommended:
in the case of pollution (according to visual check)
if there is a suspicion of erroneous measured values
if the measured value lies outside the range of precision required by
the user during the function check.
Exterior cleaning
Note
Please also observe the instructions on cleaning the electrode in the
respective operating manual.
5.4 Disposal
Armature We recommend disposing of the armature as electronic refuse.
Combination electrodes If no official regulations apply to the contrary, used and defective
electrodes can be treated as household waste.
Contamination Cleaning agents
For sludge and loosely adhering
dirt, or biological deposits
Soft cloth or soft sponge, warm
tapwater with detergent
Salt and / or lime deposits Acetic acid (volume percentage
= 20 %),
soft cloth or soft sponge

Replacement parts and accessories SensoLyt®690
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6 Replacement parts and accessories
6.1 Combination electrodes
Caution
The pressure resistance of the operable pH/ORP armature can be
restricted by the pressure resistance of the electrode (see chapter
8 TECHNICAL DATA). When selecting the electrode please make sure
it is suitable for the pressure range and temperature range
planned.
pH combination
electrodes
ORP combination
electrode
6.2 General accessories
Technical buffer
solutions for
pH calibration
Protective hood
Note
Information on further accessories is given in the WTW catalog and on
the Internet.
Model Order no.
SensoLyt®SEA
SensoLyt®DWA
SensoLyt®ECA
SensoLyt®SEA-HP
109 115
109 119
109 117
109 118
SensoLyt®PtA 109 125
Buffer (bottles of 1 liter) pH value Order no.
TEP 4
TEP 7
TEP 10
4,01
7,0
10,0
108 700
108 702
108 704
Model Order no.
SensoLyt®700 SK 109 194

SensoLyt®690 What to do if...
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7 What to do if...
Measurement delivers
no or wrong measured
values
System cannot be
calibrated
Cause Remedy
– Armature not connected – Check connection to meter
– Electrode not connected or
defective
– Check electrode and
electrode connection
– Watering cap still on the
electrode
– Pull off watering cap and
calibrate
– No or wrong calibration
performed
–Calibrate
– Electrode contaminated – Clean electrode
– Liquid has penetrated the
armature
– Armature defective, return to
WTW
– Instrument setting incorrect – Correct instrument setting
Cause Remedy
– Slope of the electrode too low – Replace electrode
– Asymmetry of the electrode too
high
– Replace electrode
– Armature is operated with ORP
electrode
– Use pH electrode

Technical data SensoLyt®690
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8 Technical data
8.1 Measurement characteristics
Measuring principle Potentiometric measurement using a combination electrode. Signal
amplifier integrated in the sensor for low impedance signal
transmission
Measuring range Depending on the built-in electrode
Temperature
measurement
8.2 Application characteristics
Temperature range
Allowed pH range of the
test sample
4 ... 12
Pressure resistance Max. allowed overpressure (sensor including connection cable):
The SensoLyt®690 meets the requirements according to article 3(3) of
the directive, 97/23/EC ("pressure equipment directive").
Sensor accuracy ± 0.3 K
Response time t99 (99 % of the final value
display after) < 15 s
Measuring medium 0 °C ... + 60 °C (32 ... 140 °F)
Storage/transport - 5 °C ... + 65 °C (23 ... 149 °F)
with installed combination
electrode,
SensoLyt®SEA, DWA, PtA
106Pa (10 bar) *
with installed combination
electrode,
SensoLyt®ECA
6 x105Pa (6 bar) *
with installed combination
electrode,
SensoLyt®SEA-HP
106Pa (10 bar) **
* temperature dependent (see safety instruction below)
** in the entire temperature range