AquaLabo LowTuS User manual

V1.2 _ April2023
LowTuS
User manual

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TABLE OF CONTENTS
1. WARRANTY 4
2. INFORMATION 5
3. SAFETY 6
3.1 Safety instructions 6
3.1.1 Safety instructions in the manual 6
3.1.2 Labels on the product 6
3.2 Operating safety 6
3.2.1 Intended use. 6
3.2.2 Unauthorized use 6
3.2.3 User qualification 6
3.3 Notes on handling 6
3.4 Packaging 7
4. OVERVIEW OF THE LowTuS SENSOR 8
4.1 LowTuS versions description 8
4.2 Package contents 8
4.3 General view of the LowTuS sensor 9
4.3 Measurement chain description and measuring principle. 11
4.4 Available parameters 12
4.5 On site installation: Wall mounting configuration 12
5. CONDITIONS OF USE 14
5.1 Fluidic circuit description 14
5.1.1 Fluidic configuration: 14
5.1.2 Compatible pipe types: 14
5.2 Fluidic circuit assembly 15
5.2.1 Pre-assembled valves descriptions: 15
5.3 INLET or OUTLET tubes: 16
5.3.1 Tube quality control: 16
5.3.2 Assembly checking: 16
5.3.3 Final locking: 16
5.3.4 Disconnection: 16
6. CONNECTION AND WIRING 17
CONDUCTORS IDENTIFICATION TABLE : 17
7. COMMUNICATION 18
7.1 General information 18
7.1.1 Communication and protocol. 18
7.1.2 Sensor address 18
7.2 Device activity 18
7.3 Measurements 18
8. MAINTENANCE/CLEANING SEQUENCE 19
8.1 Maintenance steps 19
9. CALSENS SOFTWARE 21
9.1 General description. 21
9.2 Features. 21
9.3 Calibration. 24
9.3.1 Generalities 24
9.3.2 Parameter selection 25

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a. Fluid temperature parameter 25
b. Turbidity parameter 27

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1.WARRANTY
The LowTuS equipment sold by the AQUALABO company are guaranteed against all manufacturing defects for a period of 2
years excluding consumables (unless expressly stipulated by AQUALABO) from:
-the date on which the buyer or authorized representativedeclares technical acceptance of the equipment at the factory,
-or alternatively,
▪for mainland France: from the date of the delivery note,
▪for other destinations: from the date of shipment certified by LTA, waybill, or bill of lading.
AQUALABO’s warranty applies exclusively to malfunction resulting from a design flaw or inherent defect. It is strictly limited to
the free delivery of replacement parts (except consumables) or the repair of the device in our workshops within 10 working days,
transport not included.
The following are, by express agreement, formally excluded from our warranty:
-Any economic damage, such as staff costs, loss of profit, business disruption, etc.
-Any failure due to improper use of the device (unsuitable mains power, fall, attempted conversion, etc.), lack of
maintenance by the user or poor storage conditions.
-Any failure due to using parts, not supplied by AQUALABO, on the equipment.
-Any failure due to transporting equipment in non-original packaging.
-Batteries, aerials, and in general, any item listed under "accessories".
Our customers are asked to always request our agreement before sending us a device for repair. No returns will be accepted
without the prior written consent from our after-sales service which will stipulate the return procedure. In this case, the items will
be returned in their original packaging, carriage paid, to the following address:
AQUALABO - 115 Rue Michel Marion 56850 Caudan - France
We reserve the right to reship any device received without this agreement. Regardless of the type and conditions of transport
chosen to ship the equipment for repair under guarantee, in the original packaging, the related expenses as well as insurance
costs will be the customer’s responsibility.
Any damage resulting from returning the equipment falls within the framework of the guarantee on the express condition that
customers have sent their claims to the carrier, by registered letter with acknowledgment of receipt, within forty-eight hours, with
a copy of the letter sent to AQUALABO.
For devices with a warranty form, it only applies if the form received with the device is returned to AQUALABO duly completed.
SOFTWARE WARRANTY
The software is guaranteed by the software publisher or distributor under the conditions specified in the documentation related
to those software packages.
AQUALABO does not, under any circumstances, guarantee the software packages.
By express agreement, we formally exclude from our warranty all economic damage, in particular for staff costs, loss of profit,
business disruption, etc.
Customers are informed that AQUALABO may not, under any circumstances, be held responsible for any failure or bugs the
software contain.
PROPERTY RIGHTS AND TRADE SECRETS
This document is protected by AQUALABO copyright (C) 2023 and all copyright is expressly reserved. The software supplied
with the device, or referred to, contains trade secrets and confidential information which are AQUALABO’s property. It is legally
protected by international copyright (C) law.
AQUALABO affords the user a license to use its software. This may not be divulged, used, or duplicated for back-up purposes
without written permission from AQUALABO. The beneficiary must attach a copy of this document to any fully or partially
authorized reproduction.

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2.INFORMATION
AQUALABO equipment has been designed, manufactured, tested and inspected in accordance with ISO 9001 procedures.
If the equipment is not used immediately, it should be stored in a clean, dry place. Abide by the following storage temperatures
(10-35°C).
AQUALABO equipment is carefully inspected before packaging. Upon receipt of your device, check the condition of the
packaging and if you notice an anomaly, submit the usual reservations with the carrier within 48 hours. Then consult the
packing list and check that everything is in order. Finally, if you notice that something is missing or the equipment damaged,
contact AQUALABO without delay.
LowTuS turbidimeters are entirely designed and manufactured by AQUALABO in France.
AQUALABO
90 Rue du Professeur Paul Milliez • 94506 Champigny sur Marne • France
Tel.: [phone]
Hotline: [phone]
E-mail: [e-mail]
Website: https://www.aqualabo.fr/

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3.SAFETY
3.1 Safety instructions
3.1.1 Safety instructions in the manual
This manual provides important information on how to operate the product safely. Read it carefully to familiarize yourself with the
product before commissioning and using it. This manual should be kept near the product so that the information you need is
always easy to find.
Important safety instructions are highlighted in this manual. They are indicated by the warning symbol (yellow triangle) on the left-
hand side.
CAUTION
Indicates a potentially hazardous situation that may result in product damage or destruction,
serious (irreversible) injury or even death, if the safety instructions are not followed.
3.1.2 Labels on the product
Be aware of all information labels and safety symbols affixed to the product.
3.2 Operating safety
3.2.1 Intended use
Comply with the following points for safe operation:
−Store and use the device under the environmental conditions mentioned in this manual (see Characteristics).
−Do not disassemble the device.
−Power the device in compliance with the specified DC voltage range.
−Comply with the use restrictions given below.
3.2.2 Unauthorized use
The product must not be operated if:
−it is visibly damaged (e.g. after being transported).
−it has been stored under adverse conditions for a long period of time.
3.2.3 User qualification
We assume that operators know how to manage this equipment by virtue of their professional training and experience. In
particular, the operators must be able to understand and correctly implement the safety instructions/labels when using the product.
Trained personnel should be familiar with and follow the instructions in this manual.
3.3 Notes on handling
LowTuS turbidimeters are opto-electronic devices. As such, they must be treated with care. Always protect the device from
conditions that could adversely affect its components. In particular, adhere to the following points:
➢The ambient temperature and humidity, when using and storing, must be within the limits indicated in the TECHNICAL
CHARACTERISTICS section.
➢Irrespective of the circumstances, the device must be protected from the following influences:
-Intensive exposure to sunlight and heat,
-Corrosive or caustic fluids, organic solvents, or vapor with a high solvent content.
➢As this sensor is an optical measurement device, the optical path and more particularly, the two optical windows must
be protected. Dirt and scratches may affect measurement performance.
➢All work on the inside of the instrument, must be performed by AQUALABO or by AQUALABO-approved technicians.

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3.4 Packaging
The LowTuS turbidimeter is shipped in packaging designed to protect it during transport.
It is essential that you keep the original packaging as well as the inner packing in such a way as to ensure optimum protection of
the device from impact in the event of transport.
The original packaging is also required for return transport under appropriate conditions if repair is needed. Please remember that
we shall decline any warranty claim for damage caused by unsuitable transportation.

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4. OVERVIEW OF THE LOWTUS SENSOR
4.1 Description
The LowTuS turbidimeter is an in-line water turbidity measurement device including optical system and associated electronics.
There are two versions: STANDARD, with fully free flat lid and, PREMIUM, with integrated automatic cleaning system in the lid.
STANDARD
PREMIUM
4.2 Package contents
The package consists of a LowTuS sensor with a single power and communication cable.
Cable length varies depending on the model ordered.
The LowTuS device is delivered with:
a) the pre-configurated valves unplugged,
b) locking clips for fluid circuit,
c) a quick checking solid state tool (PREMIUM version only).
Upon receipt of your device, check the condition of the packaging and if you notice an anomaly, submit the usual reservations
with the carrier within 48 hours. If you notice that something is missing or the equipment is damaged, contact AQUALABO without
delay.

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4.3 General view of the LowTuS sensor
The PREMIUM version is described below with its automatic cleaning system built into the removable lid. In this version, a specific
cable transfers energy from the main part of the LowTuS device to a motor in the lid to generate a cleaning process using a
rotating arm with a rubber blade.
1 –DEVICE ENCLOSURE with status LED
2 - POWER SUPPLY and COMMUNICATION CABLE
3 –DEVICE-TO-MOTOR CABLE
4 - FLOW CELL BODY
5 - FLUID INLET
6 - FLUID OUTLET
7 - DRAIN
CAUTION:
The main cable is used to power the sensor and communicate with a master device. The product’s
seal is not guaranteed when the sensor is suspended by its cable or when the cable is damaged
(cut or partial abrasion of the outer sheath).
1
2
3
4
6
5
7

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The premium version has a Low Turbidity sensor which
incorporates a mechanical system to automatically clean the
measuring cell. This system prevents the build-up of
contamination in the measuring field, optical scattering and IR
radiation cells.
This automatic de-bubbling system prevents bubbles from
sticking to the optical windows so as to prevent measurement
errors.
Calibration can be performed using clear water and a turbidity standard, aqueous Formazine solution, in static mode (no flow i.e.
flowcell closed by the lid).
Ensure that the standard solution turbidity value is within the range.
A solid Tare reference could be used as a quick check. This
tool is then introduced in the open and perfectly dry flow cell.
The turbidity equivalent value of the tool is factory defined for
the LowTuS device. Consequently, the tool is compatible with
a single device.
This tool contains two holes which combined with the pin fixed
in the upper part of the measuring cell allow for two positions
of use.
The first position identified as the "DARK position" represents
complete closure of the source channel window to generate a
minimal signal on the receiver.
The second position identified as the "TURBIDITY VALUE
position" equates to low intensity light transfer from the
transmitter to the receiver.
In this position, a non-zero signal is observed. It is therefore
advisable to use this tool to test if the measuring equipment is
operating correctly.
The quick check tool is an optical system. There is a specific box for safe storage.
Be sure to clean and then dry the measuring chamber with a clean tissue before inserting the tool.

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4.3 Description of the measurement chain and measuring principle
The measurement principle is based on measuring InfraRed light diffusion at 90° (ISO 7027) and enables continuous monitoring
of turbidity across low measurement ranges.
The LowTuS device is an open protocol RS485 Modbus slave. It delivers temperature and turbidity values to amaster. This master
could be either a local display-controller-transmitter or a remote monitoring system.
Figure 1: Main diagram in the MASTER/SLAVE configuration including LowTuS.
CAUTION:
The LowTuS sensor has an optical system based on an IR light source. Never look directly into the
light source. Risk of irreversible damage to sight.
CAUTION:
Intense, external light may saturate the sensor's optical system receiver and therefore distort the
measurement.

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4.4 Available parameters
LowTuS device is a digital sensor delivering the following data:
Parameter
Unit
Description
Temperature
° Celsius
Fluid temperature: measurement located in the flow cell body.
Turbidity
(Main parameter)
NTU
Two available ranges (see data sheet for details); Factory calibrated with diluted
Formazine standard solutions; Additional calibration could be implemented by the
user during the product’s life.
Turbidity with user
defined micro-offset
NTU
Taken from the main parameter given a user-defined offset. This offset could be
defined using an externally measured sample (e.g. laboratory turbidimeter). This
sample will be easily collected using the drain valve.
TURBIDITY micro-offset adjusted = TURBIDITY main parameter + Micro-offset value
The micro-offset value could be positive or negative.
Custom TSS value
mg/L
Taken from the main parameter given a user-defined offset and gain. These
specific coefficients are user-defined after sample analysis.
TSS custom = GainTSS . TURBIDITY main parameter + OffsetTSS
Coefficients could be positive or negative.
Wiper cycles
Number of
Cycles
Information about wiper aging (useful only for the PREMIUM version).
4.5 On-site installation: Wall-mount configuration
LowTuS device is a wall-mounted flow cell.
Use 4 attachment screws appropriate for the wall bracket and a mass of 3 kg (device and tubes full of water).
Type of screws:
- Ø 4 mm max.
- Ø screw head 8 mm max.
To avoid air bubbles getting trapped in the flow cell, please adjust a perfect horizontal position of the device.
CAUTION:
Wall material must be able to securely hold the device long-term.
Install the LowTuS in a vibration-free environment.

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5.CONDITIONS OF USE
5.1 Fluid circuit description
5.1.1 Fluid configuration:
The LowTuS device is compatible with analysing aqueous solutions.
Organic solvents could damage plastic parts.
Flow rates min / max: 100 ml/min –1500 ml/min
5.1.2 Compatible pipe types:
Fluid inlet and drain:
- semi-rigid in PE Ø int 10mm Ø ext 12 mm => opaque black
- flexible Ø int 10mm mounted on fluted tip => opacity recommended to reduce algae growth.
Fluid outlet:
- semi-rigid in PE Ø int 4 mm Ø ext 6 mm => opaque blue
- flexible Ø int 4 mm mounted on fluted tip => opacity recommended
CAUTION:
Fastening the hoses to the wall bracket near the product is mandatory to avoid premature wear and
tear of the couplings.
FLUID OUTLET
Semi-rigid PE 4x6 pipe or flexible pipe: internal diameter
4 mm mounted on fluted tip.
FLUID INLET
Semi-rigid PE 10x12 pipe or flexible pipe: internal
diameter 10 mm mounted on fluted tip.
CAUTION:
Fluid output must be carefully
configurated to release fluid
from a higher level than the fluid
inlet (120mm vertical gap) at
atmospheric.

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5.2 Fluid circuit assembly
LowTuS is delivered with the valves unplugged. Please only connect the two pre-configured valves, INLET and DRAIN once the
device has been wall-mounted.
5.2.1 Description of the pre-assembled valves:
INLET valve: fluted tip inserted in one side of the valve; 50mm semi-rigid 10x12 PE tube in the other side,
DRAIN valve: stopper inserted in one side of the valve; 50mm semi-rigid 10x12 PE tube in the other side.
In both cases, the semi-rigid 10x12 PE tube must be inserted into T-part under the flow cell (see arrows in the picture). Inlet and
drain valves are in position when it mechanically stops in the quick coupling. In the right position the remaining space between
the valves and the T-part is around 5mm.
CAUTION:
During the assembly (10x12 tube insertion), the operator stands the T-part manually to avoid any
mechanical stress on this part.
Inlet valve
Drain valve
Inlet valve
Drain valve

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5.3 INLET or OUTLET tubes
5.3.1 Tube quality control:
Make sure that the tube used is clean and does not present any scratches, cracks or deformity. To avoid leakage, ensure that the
tube size and the push-in system size of the fittings are the same. Cut the semi-rigid tube with the dedicated cutter tool to obtain
a 90° cut for the part of the tube to be inserted into the fittings. Before inserting the tube, check the inside of the fitting. Remove
any possible obstruction inside.
Make sure that the tube is correctly and fully inserted. Please connect the tube by hand. Inserting the tube into the fitting requires
a moderate force.
5.3.2 Assembly checking:
To make sure that the fitting is properly connected to the tube,
hold the T-part with one hand, and with the other hand pull the
tube once without releasing the collar.
5.3.3 Final locking:
After pulling, slide a locking clip of the right size between the
fitting body and the collar.
Push the tube into the fitting once more for a complete
insertion.
The use of a locking clip avoids accidental disconnection and
eliminates any play between the tube and the fitting.
5.3.4 Disconnection:
Make sure the pressure has been removed from the circuit
before disassembling the tube.
Firstly, remove the locking clip.
Push the collar in the direction of the fitting body and pull the
tube, keeping collar in the same position, near the fitting body.

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6.CONNECTION AND WIRING
The LowTuS turbidimeter comes with a factory-installed cable (of a given length) with bare wires.
CAUTION:
Any modification of the connector installed by the manufacturer, bare wires or 6-contact plug,
represents a major transformation of the product and entails a loss of guarantee.
Never exceed a voltage of 10VDC (absolute maximum rating) on communication lines RS485, A or
B, otherwise the transceiver component RS 485 could be irreversibly damaged.
SDI-12: Abide by the voltage value described in the related standard (nominal: 5 VDC)
Always connect ground + shield first.
CONDUCTOR IDENTIFICATION TABLE :
Cable length up to 15m included.
1 - Red
Power Supply, V+
2 - Blue
SDI-12
3 - Black
Weight
4 - Green
B "RS-485"
5 - White
A "RS-485"
6 -
Green/Yellow
Cable shielding
Connect wires 3 and 6 together
Cable length from 15 to 100 m
Red
Yellow
Orange
Purple
Pink
Power Supply, V+
2 - Blue
SDI-12
3 - Black
Weight
4 - Green
B "RS-485"
5 - White
A "RS-485"
6 -
Green/Yellow
Cable shielding
Connect wires 3 and 6 together

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7.COMMUNICATION
7.1 General information
7.1.1 Communication and protocol
The LowTuS sensor has one digital serial communication mode: the Modbus RTU protocol (RS485 physical medium) which
enables the exchange of information between the master device and the sensor (slave) such as, the measurement configuration,
measurement values and calibration of the available parameters.
7.1.2 Sensor address
The LowTuS sensor’s RS485/Modbus communication address is factory set. Its value is constant (80) and different from that
attributed to any other model in the DIGISENS range. The broadcast address (0) is aimed at a sensor whose address is unknown
to change its Modbus address.
These addresses can be modified by an operator wishing to manage a network of several sensors, thereby avoiding any conflict.
7.2 Device activity
An RGB LED is in the front panel of the LowTuS sensor. It gives information to the user about device activity.
LED color
Description
GREEN slow flash: breathing
Device activated; no specific action
GREEN fast flash
Measurement action
RED-GREEN flash
Measurement error
BLUE flash
Automatic cleaning system running
RED-BLUE flash
Cleaning system error
7.3 Measurements
After full assembly of the fluid circuit, connection to water supply, connection to power supply and RS485-modbus master
device, the LowTuS will provide measurements after each measurement request from the master.
The communication sequence description (timing, frames), the list of registers is available in the DIGISENS sensor modbus
documentation.
Please note that the measurement period, sliding average, number of measurements before cleaning system cycle, could be
defined by the master using the Modbus protocol.
NOTE:
Gathering temperature values is an easy way to validate the RS485-modbus communication, from connection quality, powering,
measurement requests until register readings with a slow change to ambient temperature values, reading after reading.
CAUTION:
It may take a few hours, after device set-up, to obtain signal stability for the turbidity measurement
due to global system thermic stabilization.
Any bubbles trapped in the upstream circuit of the system’s flow cell, during the installation, may
also have an impact on measurement stability. If the initial disturbances do not disappear, it may
be necessary to add a debubbling device upstream of the measuring cell.

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8.MAINTENANCE/CLEANING SEQUENCE
8.1 Maintenance steps
- Stop the wiper cleaning cycle (turn off the LowTuS device).
- Stop the fluid supply to the cell. If the drain valve is not connected to
a drain pipe, put a tank under the flow cell.
- Close the inlet valve and open the drain valve.
- To remove the device’s lid, unscrew the three M6 screws on the top.
Lid holder pin, on the top right side of the main part of the device
- Extract the lid from the flowcell with a vertical movement then put the
lid on the lid holder pin.

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-After internal cleaning or calibration process, check the
O-ring is in good condition,
-Close the flow cell, place the lid on the top of the flow cell.
The right position is obtained when the pin is in the small
hole.
-Screw the 3 points using flat washers.
CAUTION:
Do not hit the wiper arm when removing the lid or during the maintenance process.
CAUTION:
Do not hang the lid by the cable.