Xylem WTW DIQ/S 281 User manual

OPERATING MANUAL
ba77244e01 08/2020
DIQ/S 281
UNIVERSAL TRANSMITTER FOR ONE DIGITAL SENSOR
UNIVERSALTRANSMITTER
DIQ/S 281

DIQ/S 28X
2ba77244d01 08/2020
Copyright © 2017 Xylem Analytics Germany GmbH
Printed in Germany.

DIQ/S 281 Contents
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ba77244e01 08/2020
Contents
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.1 Structure and function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2 USB interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.3 Behavior of the system to a power failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1 Safety information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.1 Safety information in the operating manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.2 Safety signs on the product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1.3 Further documents providing safety information . . . . . . . . . . . . . . . . . . . . . . . 10
2.2 Safe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2.2 Requirements for safe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2.3 Unauthorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3 User qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.1 Scopes of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2 Basic principles of installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2.1 Requirements of the measurement location . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3 Safety requirements of the electrical installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.4 Installation guidelines for lightning protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.5 Connecting the sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.5.1 IQ sensor with SNCIQ cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.5.2 IQ sensor with permanently mounted cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.6 On-site mounting of the DIQ/S 28X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.6.1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.6.2 Mounting on a mounting stand with the SSH/IQ sun shield . . . . . . . . . . . . . . . . . 20
3.6.3 Mounting under the SD/K 170 sun shield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.6.4 Top hat rail mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.6.5 Panel mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3.7 Electrical connections: General instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.8 Connecting the voltage supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.8.1 DIQ/S 28X-CR2 (mains power version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.8.2 DIQ/S 28X-CR2/24V (24 V version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.9 Connections to the relay and current outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
3.9.1 General installation instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
3.9.2 Usage of the auxiliary voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.10 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.11 Installation examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.11.1 Connection of a sensor without compressed air cleaning . . . . . . . . . . . . . . . . . . 40

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3.11.2 Connection of a sensor with compressed air cleaning . . . . . . . . . . . . . . . . . . . . . 41
3.11.3 Connection of a sensor that is located at a distance
(without compressed air cleaning) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
3.12 Figures of the terminal strips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.1 Operating elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.1.1 Overview of the operating elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.1.2 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
4.1.3 Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2 General operating principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2.1 Navigating in menus, lists and tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.2.2 Entering texts or numerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.3 Access to the DIQ/S 28X with active access control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.4 Display of current measured values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.5 Messages and log book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.5.1 Message types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.5.2 Log book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
4.5.3 Viewing detailed message texts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
4.5.4 Acknowledge all messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
4.6 Calibration data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.6.1 Calibration entries in the log book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.6.2 Calibration history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
4.7 Status info of sensors and outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
4.8 General course when calibrating, cleaning, servicing or repairing an IQ sensor . . . . 60
4.8.1 Maintenance condition of IQ sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.8.2 Switching on the maintenance condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
4.8.3 Switching off the maintenance condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4.9 USB interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4.10 Info on software versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
4.11 Software-Update for the DIQ/S 281 and sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
5 Settings/setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
5.1 Selecting the language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
5.2 Terminal settings of the DIQ/S 28X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
5.3 Access control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
5.3.1 Activating the access control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
5.3.2 Activating the instrument block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
5.3.3 Electronic key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.3.4 Access to the DIQ/S 28X with active access control . . . . . . . . . . . . . . . . . . . . . . 72
5.4 Settings for sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
5.5 Editing the list of outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
5.6 Alarm settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.6.1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.6.2 Setting up / editing alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.6.3 Alarm output to display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
5.6.4 Alarm output as relay action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

DIQ/S 281 Contents
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5.7 System settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
5.7.1 Setting the date and time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
5.7.2 Location altitude / average air pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
5.7.3 Function code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
6 Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
6.1 Outputs of the DIQ/S 281 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
6.2 Basic information on relay functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6.2.1 Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6.2.2 Limit indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6.2.3 Proportional output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
6.3 Entering / editing the name of an output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.4 Linking the output with a sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
6.5 Deleting a link with an output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
6.6 Setting the relay outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
6.6.1 Relay action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
6.6.2 System monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
6.6.3 Sensor monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
6.6.4 Limit indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
6.6.5 Frequency controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
6.6.6 Pulse-width output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
6.6.7 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
6.6.8 Manual control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
6.6.9 Alarm contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
6.7 Setting the current outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
6.7.1 Recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
6.7.2 PID controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
6.7.3 Fixed current value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
6.8 Checking the condition of the outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
6.9 Behavior of linked outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
6.9.1 Behavior in case of error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
6.9.2 Behavior in non-operative condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
7 Maintenance and cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
7.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
7.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8 What to do if ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115
8.1 Information on errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
8.2 Errors: causes and elimination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
8.3 Replacing system components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
8.3.1 Replacing passive components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
8.3.2 Replacing the IQ sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
9 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
9.1 DIQ/S 281 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

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9.2 DIQ/JB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
9.3 DIQ/CHV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
9.4 Space required by mounted components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
10 Accessories and options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
11 Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
11.1 Explanation of the message codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
11.1.1 Error messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
11.1.2 Informative messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
12 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

DIQ/S 281 Overview
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1Overview
1.1 Structure and function
One digital single sensor (one sensor for one main parameter) can be con-
nected to the universal transmitter DIQ/S 28X.
This means one main parameter (e.g. pH, D.O., turbidity value...) and one
secondary parameter in addition (e.g. temperature) can be displayed and
administrated.
Each sensor is automatically recognized after being connected and immediately
starts measuring.
The universal transmitter has two relay outputs and two current outputs to be
connected to existing process control systems.
Branches The DIQ/JB branching module (accessory) is a simple passive module for the
branching or extending of SNCIQ lines.
Relay and current
outputs The relay- and current outputs can be linked with the sensor. Linked outputs can
be used to monitor sensors and for the output of measured values.
A relay output can be programmed as:
Monitoring relay
Limit monitor
Proportional output of measured values (pulse width or frequency output)
Control unit of a sensor cleaning system driven by compressed air.
A current output can be programmed as:
Analog output
PID controller
Compressed air-
driven cleaning
system
The universal transmitter DIQ/S 28X is prepared for the compressed air-driven,
time-controlled sensor cleaning function. For this, a DIQ/CHV valve module and
if necessary a CH cleaning head is required (both available as accessories). The
cleaning procedure is controlled by the Universal Transmitter. The universal
transmitter provides the supply voltage and control relay for the compressed air
valve in the DIQ/CHV valve module. This enables a simple setup and uncompli-
cated wiring.
Suitable sensors for the universal transmitter DIQ/S 28X are listed
in the WTW catalog or on the Internet.

Overview DIQ/S 281
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Example of a
simple system
figure 1-1 Simple systems with one sensor
1.2 USB interface
The USB interface of the DIQ/S 281 provides the following functions:
Connection of a USB memory device to carry out a software update (see
section 4.11)
Connection of a USB memory device to be used as an electronic key for sim-
ple access to the system when access control is switched on (see
section 5.3.3)
Connection of a USB hub for the reproduction of the USB interface.
Note:
The USB interface is designed for USB memorydevices with a maximum power
consumption of 1 watt. USB memory devices with a higher power consumption
have to be supplied with power by an extra power supply. If these instructions
are not complied with, the availability of the system can be adversely affected.
DIQ/JBDIQ/JB
Universal transmitter
DIQ/S 28XCR2
IQ sensor, digital

DIQ/S 281 Overview
9
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1.3 Behavior of the system to a power failure
The system configuration is permanently retained. It consists of the following
settings:
– Sensor settings
– Settings and links of the relay outputs
– Settings of the current outputs
– System settings (display language, air pressure/altitude, passwords etc.)
Linked relay outputs switch to the non-active condition (open).
Current outputs switch to the non active-condition (0 mA).
A restart is carried out automatically when the power returns. The continues
working with the settings of the time prior to the power failure.
If the power failure lasted several hours the system clock has to be reset.
The USB interface is equipped with a protective cover.
Only remove the protective cover when you want to connect a USB
device. Immediately close the USB connection again when you
have removed the USB device.
When the USB connection is open, there is a danger of corrosion.

Safety DIQ/S 281
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2 Safety
2.1 Safety information
2.1.1 Safety information in the operating manual
This operating manual provides important information on the safe operation of
the product. Read this operating manual thoroughly and make yourself familiar
with the product before putting it into operation or working with it. The operating
manual must be kept in the vicinity of the product so you can always find the
information you need.
Important safety instructions are highlighted in this operating manual. They are
indicated by the warning symbol (triangle) in the left column. The signal word
(e.g. "CAUTION") indicates the level of danger:
indicates a situation where goods might be damaged if the actions mentioned
are not taken.
2.1.2 Safety signs on the product
Note all labels, information signs and safety symbols on the product. A warning
symbol (triangle) without text refers to safety information in this operating
manual.
2.1.3 Further documents providing safety information
The following documents provide additional information, which you should
observe for your safety when working with the measuring system:
Operating manuals of other components of the measuring system
Safety datasheets of calibration and maintenance equipment (e.g. cleaning
solutions).
WARNING
indicates a possibly dangerous situation that can lead to seri-
ous (irreversible) injury or death if the safety instruction is not
followed.
CAUTION
indicates a possibly dangerous situation that can lead to slight
(reversible) injury if the safety instruction is not followed.