aquasant AS 2.0 D24 User manual

Operating manual
Safety Liquid Switch
AS 2.0 (2.1) D24 Control Device, 1-channel, SIL2
for connecting electro-optic overfill protection systems,
conductivity detectors and Namur sensors
in 2- and 3-wire configurations

AS 2.0 D24
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Change index
Version
Date
Description
1.00
04/2021
First version for firmware 1.00

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Document information
Distribution: Aquasant Messtechnik AG
Hauptstrasse 22
CH - 4416 Bubendorf
T [phone]
[e-mail]
www.aquasant.com
Production: Aquasant Messtechnik AG
CH-4416 Bubendorf
Manual No.: VEB-Device_AS20D24G [Manual].docx
Version: 210422/1
Firmware: AS 2.0 D24: V1.00
Pages: 40
Changes: Subject to change without notice
© 2021 Aquasant Messtechnik AG claims copyright protection for this document. The
document may not be modified, supplemented or reproduced without prior written
consent.
We reserve the right to make changes to technical details with regard to the description, information
and illustrations in these operating instructions.

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Table of contents
1Information about this document 6
1.1 Target group 6
1.2 Symbols 6
1.3 Supplementary documentation 7
2Safety instructions 8
2.1 General safety instructions 8
2.2Authorised personnel 8
2.3 Intended use 8
2.4 Product safety 8
2.5 Functional approvals 9
3Product information 10
3.1 Basic functions 10
3.2 Special functions 11
3.3 Applications 11
4Installation 14
4.1 Conditions for assembly 14
4.2 Control device assembly on DIN rail 14
4.3 Electrical connections 16
5Operation and parametrisation 19
5.1 Description of the device 19
5.2 Operation 23
5.3 Display and operating module 24
6Initial commissioning 29
6.1 Checking installation 29
6.2 Servicing and troubleshooting 30
6.3 Procedure for repair 30
6.4 Device malfunction 31
6.5 Removal 33
7Appendix 34
7.1 Technical data 34
7.2 Commissioning test report 38
7.3 Declaration of conformity 39

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List of figures and tables
Figure 1 Row of control devices with TBUS connector............................................................10
Figure 2 Using special overspill protection with AS2.0 and AS2.2 - schematic.......................12
Figure 3 Using special overspill protection with two AS2.0 devices - schematic ....................12
Figure 4 Using leakage monitoring - schematic .....................................................................13
Figure 5 Using oil detection with LS - schematic.....................................................................13
Figure 6 Arrangement for installing the AS2.* .......................................................................14
Figure 7 Installing on DIN rail according to NS35 DIN EN 60715............................................15
Figure 8 Device dimensions; top view, side view ....................................................................15
Figure 9 Connection diagram for the AS2.0 D24 G.................................................................18
Figure 10 Nameplate for the AS 2.0 D24 ................................................................................20
Figure 11 DIN rail disassembly................................................................................................33
Table 1 Sensor selector switch ................................................................................................21
Table 2 6-way DIL switch (address) – Device 1 .......................................................................22
Table 3 6-way DIL switch (address) – Device 2 .......................................................................22
Table 4 6-way DIL switch (address) – Device 3 .......................................................................22
Table 5 Description of button functions..................................................................................23
Table 6 Button combinations..................................................................................................23
Table 7 Order of parameters - Description of functions .........................................................25
Table 8 Selector switch parameters (settings)........................................................................28
Table 9 Selector switch parameters – Description of functions..............................................28
Table 10 Menu parameters - Description of functions ...........................................................28
Table 11 Status error messages..............................................................................................31
Table 12 Error messages - Troubleshooting ...........................................................................32

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1Information about this document
This manual provides the information you need to install, connect and commission the
device, as well as important instructions for maintenance, troubleshooting, replacing parts
and user safety. You must therefore read the manual before commissioning and keep it
accessible at all times as part of the product in the immediate vicinity of the device.
1.1 Target group
This operating manual is intended for trained specialists. The contents of this manual must
be made accessible to each specialist and must be applied.
1.2 Symbols
A yellow triangle indicates a warning. Each warning sign is provided.
1.2.1 Warnings
Explosion protection symbol
Observe the warnings to ensure explosion protection.
Electrical symbol
Observe the warnings for hazards with electrical voltage.
Attention symbol
Pay special attention to the instructions.
Operating symbol
Follow the instructions for operating the control device
Maintenance symbol
Information regarding maintenance
Manual symbol
Follow the instructions and information.

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1.3 Supplementary documentation
1.3.1 Standard documents
ATEX test certificate
EMC certificate of conformity
QA documentation
Swiss Association for Technical Inspections (SVTI) test report (equipment for water-
polluting liquids)
1.3.2 Device-specific additional documentation
Technical data: VDT-aquasant_AS2.0-D24
Quick start guide (included with the delivery)

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2Safety instructions
2.1 General safety instructions
This device is built and tested in accordance with the safety requirements for electronic
instrumentation. It is only possible to guarantee that the device will function correctly and
that it can be operated safely if the generally applicable safety precautions and the device-
specific safety instructions in this operating manual are observed during use.
2.2 Authorised personnel
All the operations described in this documentation may only be carried out by trained
specialists who are authorised by the plant operator. Always wear the required personal
protective equipment when working on and with the device. The device is a piece of
electronic equipment for use in closed electrical operating areas to which only qualified
electricians or persons trained in electrical engineering have right of entry or access.
The personnel must meet the following requirements for their activities, such as
commissioning or maintenance:
‣Trained specialists have qualifications appropriate to the role and activity
‣Authorised by the plant operator
‣Familiar with national regulations
‣Instructions in the manual and additional documentation have been read and understood
‣Follow instructions and conditions
2.3 Intended use
•AS2.*-D24 with intrinsically safe Ex output on aquasant® liquid sensors, conductivity
detectors and NAMUR devices (ATEX Directive 2014/34/EU)
•Only connect suitable transducers
•The device may cause hazards if it is used improperly
•Only use insulated tools
•Only use original parts
2.3.1 Warning against misuse
The manufacturer is not liable for damage resulting from improper use or use that is not in
accordance with the intended purpose. Any other conditions of use negatively affect the
protection. It is not possible to guarantee that the device will function correctly.
2.4 Product safety
This device is built and tested to be operationally safe, according to the current state of the
art and good engineering practice. The device has left the factory in perfect condition in
terms of safety.
2.4.1 EU conformity
The device complies with the legal requirements of the applicable EU directives. The
directives are listed with the applied standards in the applicable EU declaration of
conformity. By affixing the CE mark, aquasant® confirms that the device has been successfully
tested.

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2.4.2 SIL conformity
SIL (Safety Integrity Level) 2 hardware/software according to IEC 61508.
Functional Safety of Electrical/Electronic/Programmable Electronic Safety-Related Systems.
2.4.3 RoHS conformity
This product complies with the provisions of Directive 2011/65/EU of the European
Parliament and of the European Council on the restriction of the use of certain hazardous
substances in electrical and electronic equipment (RoHS) and its amendments.
2.4.4 NAMUR Recommendations
NAMUR is the User Association of Automation Technology in Process Industries in Germany.
The recommendations issued by NAMUR are considered to be standards in field
instrumentation. The device meets the requirements of the following NAMUR
recommendations:
• NE 21 – Electromagnetic Compatibility of Equipment
• NE 53 – Compatibility of field devices and display/adjustment components
For more information, go to: www.namur.de.
2.5 Functional approvals
2.5.1 Switzerland; Swiss Association for Technical Inspections
(SVTI)/Swiss Conference of Heads of Environmental
Protection Services (KVU)
Approved for plant components for water-polluting liquids in Switzerland according to KVU
(Conference of the Heads of Environmental Protection Services in Switzerland).
Filling protection: KVU No.: 301.001
Special overspill protection: KVU No.: 302.004
Leakage monitoring: KVU No.: 321.003
2.5.2 Ex according to ATEX
Control devices with intrinsically safe output, approved for the connection of defined liquid
sensors, sensors and detectors in the Ex zone according to SEV ATEX21.
The EU type examination certificate must be observed. It is particularly important to
comply with the "Special conditions" contained in the certificate. Ex certification
according to Directive 2014/34/EU
Scan; PDF downloade: ATEX documentation

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3Product information
3.1 Basic functions
Limit monitoring is an important safety function to prevent overfilling of liquids in storage
tanks. Electro-optical overfill protection with the AS* control devices is proven technology
that is now moving to the next generation. The multi-functional control and monitoring
device can be universally parametrised with a wide range of sensors and is operated with 2-
or 3-wire sensors. The single-channel basic device allows you to add further basic devices
with SIL2 standards via the loop power supply. Further expansion sensor modules can also
be connected to a basic device.
The AS 2.2 D24 sensor modules expand the AS 2.0 D24 basic device with additional
intrinsically safe sensor outputs. The basic device handles the display for error message
monitoring from max. three expansion modules.
Figure 1 Row of control devices with TBUS connector
The AS2.0 basic module is monitored up to the sensor in accordance with the Namur EN107
standard. For the 3-wire electro-optical systems, the current sensor reading is monitored and
provides early warning of sensor failure, thereby assisting in the maintenance and servicing
of equipment. The basic device offers a wide range of alarm outputs.
Switch
contact
*ISB *ESB
Description LED indicator on
front
HL alarm
OUT 1
relay
0.5s
2s
Relay output; redundant, monitored
(SIL) with two independent switch-
over contacts
Yellow continuous
HL alarm
OUT 2
Opto
coupler
∆t
∆t
NPN open collector output; 0-60s
time delay
ON-delay or OFF-delay:
if the delay is active:
Yellow flashing
quickly for delay
time, then
Yellow continuous
HL alarm
OUT 3
relay
1s
1s
Relay output; can be acknowledged
via external button or "Reset" button
on front of device, potential-free
switch-over contact for an external
alarm (horn)
Yellow continuous,
flashing after
acknowledgement
Fault
message
K4 relay
1s
Relay switch contact
(Display with error message)
4-colour LED
according to Namur
*ISB=Immersion switching behavior / *ESB=Exchange switching behavior

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The "Test" button is used to check that the control device is working. All relay outputs de-
energise, OC is blocked, LEDs and acoustic buzzer are activated.
The control device communicates with the extension modules via the RS485 interface, which
is connected via the T-bus. Communication can be passed directly to the PLC via the A/B
interface outputs. The basic functions via fail-safe high (FSH)/fail-safe low (FSL), time delays,
acknowledgement reset time and internal alarm buzzer can be parametrised via the Quick
DIL switch.
3.2 Special functions
A potentiometer can be connected externally for the time delay of the OC alarm output. The
sensor sensitivity can also be adjusted using an external potentiometer. This option applies,
for example, when measuring in glass containers with strong reflections or when there is a
bubbling effect on the glass. The alarm acknowledgement can be confirmed directly on the
device or via an external button.
The AS2.1 device version performs the following two functions when unloading via road
tanker, in combination for filling protection:
If the 3-pole connector from the road tanker is connected to the filling protection, the signal
is received from the road tanker and enabled as a relay contact. This means that the enable
signal can be transmitted to the PLC or directly to the slider so that it is closed. This ensures
that the surface water is monitored.
If there is an alternative system for instrumentation at the tank farm as overfill prevention,
which is also designed to function as filling protection, the AS2.1 control device provides an
enable signal for the road tanker, which is interrupted as soon as the overfill protection in
the tank responds.
3.3 Applications
The AS2.x D24 is used for the described sensors at tank farm/filling stations to monitor limit
levels.
The safety liquid switch forms an intrinsically safe sensor circuit with the sensor, which can
be used in explosion-risk areas. It can be used to monitor liquid limit levels for petrol, mineral
oils, acids, alkalis, solvents and other chemicals, as well as all types of liquids.
The control device with associated sensor meets the requirements for use with water-
polluting materials according to KVU (CH).
3.3.1 Use according to KVU (CH)
Special overspill protection KVU No.: 302.004
Liquid sensor types: AF1S*, -21, -23, -33, -42, -26, -
Leakage detection system with sensor KVU No.: 321.003
Conductivity detector types: LS11, -12, -13, -21
Liquid sensor types: AF1S*, -21, -23, -33, -42, -26
Filling protection system KVU No.: 301.001
Liquid sensor types: AF1IR*

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3.3.2 Special overspill protection
Possible applications: Monitoring containers, tanks, tankers, drainage shafts, waste water
treatment plants, sewage treatment plants, basins, weighing tanks, pipelines, filling devices,
water supply systems, water overflows, oil separators, leakage monitoring of catch basins,
room monitoring, dry-running protection for pumps, etc.
Storage
tank
External
acknowledgment
99%
SPS
97%
AS2.0 D24
24 VDC
230 VAC
CBA
A2
A1
AS2.2
D24
HL-Alarm
C
BA
T-BUS
RS485
bl sw gr
bl sw gr
Reset
4
3
HL alarm NPN OC
acknowledgment / HL alarm / delayed delay / Fault
message redundant
Relay 3 Relay 1.1 Relay 1.2 OC 2 Relay 4
Relay de-energized
in alarm condition
AF *
overfill protection
Figure 2 Using special overspill protection with AS2.0 and AS2.2 - schematic
Storage
tank
97%
Storage
tank
External
acknowledgment
97%
AS2.0 D24
24 VDC
230 VAC
CB
A
A2
A1
bl sw gr
Reset
4
3
Relay de-energized
in alarm condition
AF *
overfill protection
AS2.0 D24
CBA
bl sw gr
TBUS TBUS
SPS
HL alarm NPN OC
acknowledgment / HL alarm / delayed delay / Fault
message redundant
6 General alarm + 24V
7 Acknowledgment
Relay 3 Relay 1.1 Relay 1.2 OC 2 Relay 4
Figure 3 Using special overspill protection with two AS2.0 devices - schematic

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3.3.3 Leakage monitoring
Possible applications: Monitoring dome shafts, retention basins, and troughs
Storage
tank
External
acknowledgment
AF
SPS
97%
AS2.0 D24
24 VDC
230 VAC
CB
A
A2
A1
AS2.2
D24
HL-Alarm
CBA
T-BUS
RS485
bl
sw gr
bl sw gr
Reset
43
HL alarm NPN OC
acknowledgment / HL alarm / delayed delay / Fault
message redundant
AF * overfill protection
Relay de-energized
in alarm condition
AF * Leakage monitoring
Relay 3 Relay 1.1 Relay 1.2 OC 2 Relay 4
Figure 4 Using leakage monitoring - schematic
3.3.4 Oil detection monitoring
Possible applications: Monitoring rainwater in a basin for heavy or light oil leaks
Storage
tank
LS21.1 * surface oil detection
Leakage monitoring
External
acknowledgment
LS
SPS
97%
AS2.0 D24
24 VDC
230 VAC
C
BA
A2
A1
AS2.2
D24
HL-Alarm
C
BA
RS485
T-BUS
RS485
bl sw gr
bl sw gr
Reset
43
AS2.2
D24
HL-Alarm
CBA
T-BUS
RS485
bl sw gr
AF
Relay de-energized
in alarm condition
AF * overfill protection
AF * Leakage monitoring
HL alarm NPN OC
acknowledgment / HL alarm / delayed delay / Fault
message redundant
Relay 3 Relay 1.1 Relay 1.2 OC 2 Relay 4
Figure 5 Using oil detection with LS - schematic

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4Installation
4.1 Conditions for assembly
Do not assemble damaged or dirty equipment. Avoid direct sunlight when operating
outdoors and in warmer climatic regions. The device is designed with protection class IP20
according to IEC/EN 60529. The device is designed to be assembled on a 35mm DIN rail
according to EN 60715. Only use the device when stationary. The device may only be installed
and operated in an environment that ensures pollution degree 2 (or better) according to
IEC/EN 60664-1. Only power supply units that match the parameters for supplying the device
may be connected as power supply modules. All circuits connected to the device must comply
with over-voltage category II (or better) according to IEC/EN 60664-1. Observe the
installation instructions according to IEC/EN 60079-14. The device may only be installed and
operated if the device is installed in an enclosure that meets the requirements for enclosures
according to IEC/EN 60079-0, which is designed with IP54 protection according to IEC/EN
60529.
•Install outside the potentially explosive area in a control cabinet
•Install with protection against weather and impact
•Avoid direct sunlight when operating outdoors and in warmer climatic regions.
•Do not assemble the control device near a heat source. The device should be well
ventilated; avoid accumulation of heat
•Install the device in a safe place so that no one can accidentally touch the device
and be injured by it.
4.2 Control device assembly on DIN rail
4.2.1 Installing Ex devices
Figure 6 Arrangement for installing the AS2.*
Connecting another device type
B DIN rail according to EN 60715 TH35-7.5/15

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Compliance with the required flashover clearance of ≥ 50 mm
The horizontal installation position provides better heat dissipation than the vertical
installation position.
If several AS2.* devices are used, the T-bus connector should be used. The T-bus is snapped
into the DIN rail and is pushed in and connected with further connectors. The T-bus connector
stays in the DIN rail when the device is removed.
Place the control device on the standard rail and press downwards/backwards until the DIN
rail engages.
Figure 7 Installing on DIN rail according to NS35 DIN EN 60715
4.2.2 Enclosure dimensions
Figure 8 Device dimensions; top view, side view

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4.3 Electrical connections
The AS2.* D24 is a DIN rail control device that is operated at 24 V DC. The removable
terminals make connection and the control cabinet build easier. For servicing, they allow the
device to be replaced quickly and without errors. The convenient plug-in connections have a
1.5mm2push-in length, so the stranded wire is inserted directly without a wire end ferrule.
The intrinsically safe Ex connection has blue connectors.
The T-bus loop power supply provides the 24VDC supply voltage, the RS485 bus, the error
signalling contact and the level alarm acknowledgement, when several devices are connected
together. The T-bus connector is not required for single devices.
Never touch live parts! Live parts can cause an electric shock, which can lead to serious
injury or even death. Whenever possible, use power cables with an upstream residual-
current circuit breaker (RCCB) (rated tripping current: max. 30 mA).
The connection values for the power supply must be observed, as stated in the
technical data or on the connection diagram. If the mains is heavily contaminated, a
mains filter or mains stabiliser is recommended.
The cross-section of the sensor connection cable should be at least 0.75mm2. The
sensor connection cables must be laid separately and at a distance from high-voltage
and high-frequency cables. In areas with potentially explosive atmospheres, the
installation regulations must be observed (EN 60079-x/ATEX Directive 2014/35/EU).
Sensor connection cables must, whenever possible, be routed via a suitable, sealed
connection box with screw fitting (max. 5m from sensor). It must be possible to check
the sensor. When stripping the sheathing, care must be taken not to damage the
insulation of the individual wires or strands.
If the cables are routed via junction boxes, a wiring diagram must then be drawn up.

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4.3.1 EMC protection
Input, output and power supply cables must not be routed in areas that have sources of
electromagnetic interference!
Sources of interference may include, but are not limited to, relays, contactors, motors and
their controls, including thyristor controls and the cables connecting those units. Blue Ex
cables must not be routed together with cables of the same type in the same duct. The locally
applicable regulations for the installation of electrical systems must be observed.
The sensor connection cables must be neatly separated and laid at a distance from
high-voltage and high-frequency cables. In intrinsically safe systems, the sensor
cables must be sheathed in blue (marking).
The type of sensor and device must match and correspond to the application (product-
related use, Ex zone, lightning protection, etc.). The system must be checked to ensure
its function with original fluid (or non-hazardous replacement fluid, e.g. water) for
commissioning and service checks.
The intrinsically safe circuits of the devices (light blue marking on the device) may be
routed into the potentially explosive area (observe the zones). The intrinsically safe
circuits must be installed in accordance with the applicable erection regulations and
with EN 60079-14.
4.3.2 Connector coding
All connectors are coded by Aquasant.
The labelled, coded connectors are equipped with push-in
terminals for quick wiring with stranded wires.
4.3.3 Eight-pole mounting rail bus connector
Increases the flexibility when using the enclosure:
Simply connecting individual control device enclosures to each
other using 8-pole mounting rail bus connectors with serial and
parallel contacts reduces the amount of work for wiring.
The bus connector is plugged together and clicked onto the top
hat rail. The bus connector stays in the DIN rail when the control
device is detached. The T-bus connector is used
Item No.: 21.01.32.187 to interconnect several AS2* DIN rail
devices. The 24 V DC power supply (for max. 10 devices), RS485
bus, fault signal contact and acknowledgement are looped
through.
The connector for the T-bus with a nominal cross-section of
0.5 mm², nominal current of 6A and rated voltage (III/2) of 160V,
is used to connect to the second DIN rail row or to the PLC.
Item No.: 21.01.32.187-1 connector
Item No.: 21.01.32.187-2 socket

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A maximum of 10 basic modules may be supplied with 24 V DC via the T-bus
connectors.
For more than that, the supply voltage must be connected again via terminals
A1/A2. If the product's connectors are not coded, there is not enough protection
against mixing up the connectors.
4.3.4 Electrical connection diagram
AS2.0 D24
Safety liquid switch device
AB
D
C-
A
A1+ A2-
RS485 A
RS485 B
2422
21
14
12
11
4
3
2
1
230 VAC 1A
Power supply 24VDC, A1+ / A2-
Sensor connection
B/C: LS11/13/21, LW9/VE9
C/D: Namur-Sensor
A/B/C: AF1*/6/21/23/26/33/35/42
Acknowledgment HL alarm
Acknowledgment, impulse +24VDC
Collective alarm fault +24VDC
Power supply -24VDC
HL alarm OC delayed output
Relay 1.1 HL-Alarm output
Relay 3 HL alarm output can
be acknowledged for horn
Sensor sensitivity
Alarm OC time delay
CB
A
32 34
Relay fault message output
Relay 1.2 HL-Alarm output
-
-
RS485
41
6
542
31
B+
com
-
USB-C
-
+
sensor selector switch
Power supply +24VDC
2422
21
T-BUS
Plug socket
1 2 3 4 5 6 7 8
RS485 C
Safe area Hazardous area
+
-
Relay de-energized
in alarm condition
230 VAC 1A
230 VAC 1A
1
2
3
4
5
6
20
34
32
31
14
12
11
42
41
6
5
Figure 9 Connection diagram for the AS2.0 D24 G
The control device relay outputs are galvanically isolated and currentless. The
currentless state or alarm state are the same (relay de-energised).

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5Operation and parametrisation
5.1 Description of the device
1. Grey push-in connector
terminals
Relay 1.2 output, high alarm
2. Grey push-in connector
terminals
Relay 1.1 output, high alarm
3. Grey push-in connector
terminals
Power supply, 24 V DC/RS485
4. Not used in this version
[Grey push-in plug terminals,
potentiometer/external
acknowledgement]
5. Grey push-in connector
terminals
Relay 3 output
6. Grey push-in connector
terminals
OC/relay 4 output
7. Device status and power
indicator, RGB LED
8. Test button
9. Liquid level alarm relay,
yellow LED
10. OC output time-delayed,
yellow LED
11. Liquid level alarm relay (can
be acknowledged), yellow
LED
12. DIL switch device functions,
quick (settings)
13. Enclosure PA (polyamid)
14. Function display 2.9"
15. Enter button
16. T-bus connector in DIN rail
17. Reset button
18. DIL switch for bus addressing
(address)
19. DIN rail snap lock
20. Push-in connector terminals
[Ex ia], connections on blue
header
21. Sensor selector
22. USB-C socket

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5.1.1 Nameplate
Left side Right side
Figure 10 Nameplate for the AS 2.0 D24
5.1.2 Scope of delivery
The scope of delivery of the AS2.x control device consists of:
•Control device type: AS 2.x D24 for DIN rail mounting
•x7 connectors (AS2.0), coded
•Quick guide and Ex documentation (optional), printed
The following are accessories:
•USB interface cable
•T-bus connector, Item No.: 21.01.32.187
•T-bus connector, Item No.: 21.01.32.187-1
•T-bus socket, Item No.: 21.01.32.187-2