Aqua-Meter Clamp with Wi-Fi

Version: 1.0

Product Description

The water sensor clamp measures the flow and temperature in a water pipe using a "Time of Flight" measurement method and transmits the data wirelessly. By analyzing the flow internally, water leaks and other anomalies are detected, and the owner is alerted.

The device is clamped onto the outside of the water pipe without interrupting the water supply. Its flexible design and innovative software allow it to be used on water pipes between 16 and 50 mm, with all currently available materials on the market such as PEX, PEX AL, copper, PE, or steel. It meets all requirements of the European Community's Measuring Instruments Directive (MID). With only 60 mm of space required above the water pipe and a length of 110 mm, the device is very flat and short, making it easy to install.

The device can be powered either via USB-C or two AA alkaline cells. Whenever an external power source is available, it is used independently of the inserted batteries.

The system communicates via Wi-Fi and is controlled by an app on a mobile phone. Additionally, data can be sent to an MQTT server or an HTTP 'webhook' to be integrated into a smart home system.

Measurement Principle

The water sensor clamp utilizes ultrasonic waves and the "differential time of flight (DTOF)" method to measure water flow. In this method, two ultrasonic transducers, called transducers, are employed to send signals in opposite directions through the pipe and water. The signal sent by the upstream transducer travels along the direction of water flow and is detected by the downstream transducer. The second signal sent by the downstream transducer moves against the direction of water flow, progresses more slowly, and meets the upstream transducer later. The difference in travel time between the two signals is directly proportional to the speed of the water in the pipe and thus the flow rate. To better understand this method, one can imagine it like swimming in the current of a river. By swimming upstream and downstream and comparing the time it takes to cover the same distance in each direction, one can estimate the speed of the water flow in the river. Similarly, in the case of the water sensor clamp, the movement of the transducers generates a wave that serves as a swimmer to estimate the speed of the water flow.

The test signal of the device has a frequency of 1 MHz and is of very low power, making it inaudible and harmless to humans and animals. Furthermore, the sound waves of this high frequency are strongly attenuated by the atmospheric pressure of the air and, in practice, cannot radiate beyond the pipe. Therefore, the water sensor clamp will not disturb people or other devices.

Design of the Sensor

The sensor consists of two main components:

Two small intermediate adapters (14) are required to fix the base to the pipe, which correspond exactly to the diameter of the water pipe. A selection for the important pipe diameters is included with the product. Furthermore, the sensor must be securely mounted to the water pipe using a cable tie or alternatively a hose clamp (not shown in the image).

During operation, the capsule is firmly connected to the base. For maintenance purposes or for battery replacement, it can be safely separated from the base. If the capsule is powered without the base, a corresponding alarm message will be issued, and no water consumption measurement is possible.

Overview of the ultrasonic transducer Overview of the ultrasonic transducer


The installation location and proper attachment of the sensor to the pipe have a decisive influence on the accuracy of the measurement. An unfavorable installation location or incorrect attachment of the sensor can, in extreme cases, result in the sensor not providing any measurement results.

Finding Suitable Installation Locations

(1) For accurate measurement, the water must be free from turbulence and air bubbles. Therefore, the device should not be installed near pipe bends or other water installations such as main shut-off valves, check valves, or pressure reducers. It must be ensured that there is a minimum distance of 20 cm on each side of the pipe bends, etc., and that the installation point does not allow accumulation of small air bubbles, which occur whenever water flows quickly through the pipe. The figure below provides some hints for the best installation position.

Installation instructions for the ultrasonic clamp-on sensor

(2) The pipe at the installation site must be smooth and free of rust, so that there are no air pockets on the outside to disrupt the measurement process. For plastic pipes, cleaning the surface is sufficient, while for metallic pipes, it may be useful to polish them with fine sandpaper.

(3) Lastly, the installation site must be reachable by radio. A stable radio connection is easiest to test by integrating the sensor into the radio network even before the final installation. Details can be found in the following section 'Connection to the Radio Network'.


Preparing Sensor for Installation

It is recommended to connect the sensor to the radio network at the location of installation, but before the final mounting on the water pipe. However, this is not a prerequisite for installation.

  1. From the set of spacers, select the two parts corresponding to the pipe diameter and insert them next to the transducers (1 in the figure below) into the corresponding slots.
  2. The transducers on the sensor base are adjustable using the small handwheel on the side, allowing them to be adapted to different pipe diameters and materials. The transducers can be extended up to 26 mm apart. Table 1 provides the necessary distance in millimeters for various pipe diameters and materials. If the pipe is sheathed (for example, PEX with aluminum sheath or copper with plastic sheath), then the base material from the table should be selected. The distance should be set with an accuracy of +/- 2 mm.

    Adjustable ultrasonic transducers

    Diameter20 mm26 mm33 mm42 mm56 mm
    Steel0 mm5 mm15 mm20 mm26 mm
    Copper0 mm0 mm5 mm13 mm20 mm
    PEX0 mm0 mm5 mm20 mm20 cm
    PP0 mm0 mm5 mm15 mm18 mm
    Table 1: Transducer distances depending on the water pipe used

  3. Remove the red protective film from the contact pads of the transducers. The buffer pads are very sticky and will hold the sensor in place without further fixation. Initially, press the pads only lightly so that they can be repositioned if necessary. If you damage one or both pads while removing them, replacement pads are included with the product.
  4. Paying attention to the flow direction (large arrow on the device's nameplate), attach the sensor to the water pipe and loosely fix it with the cable tie.


Mounting the Sensor on the Pipe

The exact positioning of the sensor on the pipe is crucial for the device's functionality and accuracy. The following variables must be considered:

  1. The sensor must be mounted absolutely parallel to the pipe. The spacers help achieve this goal.
  2. The sensor must have a defined distance from the pipe, which is completely filled by the contact buffers. The spacers also help achieve this goal.
  3. The contact pressure of the sensor must be optimal. This needs to be optimized during installation itself. A positioning aid is available for this purpose.

Position of the Ultrasonic Transducers

After the sensor is powered, an electronic positioning aid is available for optimal alignment.

The positioning aid is activated by pressing the button for three seconds and works like a car's parking aid. The start position is indicated by a solid yellow LED. As the sensor gets closer to the optimal position, the LED color changes faster, and the buzzer beeps more frequently.

The perfect position or contact pressure is indicated by a solid green LED and continuous beeping. A simple press of the button ends the positioning aid. An acceptable positioning is achieved not only with a solid green LED but also when the green LED and buzzer are interrupted only by short pauses.

The positioning aid is activated by pressing the button for three seconds and works like the parking assist in a car. The LED indicates insufficient (red), adequate (yellow), or good (green), and the length of the pause between the tones indicates the 'distance' to the target. The perfect position or the perfect contact pressure is indicated by a continuous green LED and a continuous tone. Sometimes, this position is not achievable. The green LED then indicates when there will be functional measurement results.

The positioning aid can be started at any time during operation. Pressing the button for more than two seconds starts the process without subsequent calibration, and pressing the button for more than three seconds starts the aid with subsequent calibration. A button press ends the process in both cases.

What to Do if the Positioning Aid Fails?

The distances in Table 1 are theoretical optimal values. There can be slight deviations on a real pipe. If the positioning aid does not succeed, a slight adjustment of the transducer distance may help.

Furthermore, the supplied ultrasound gel can be used to achieve an optimal acoustic connection between the sensor and the water pipe.

Especially for steel pipes with a very rough surface, the contact pressure achieved by the cable tie may not be sufficient. In this case, use a hose clamp.

Check in any case:

Special Considerations for Steel Pipes Steel pipes are challenging for the ultrasonic measuring principle for several reasons. The unevenness on the surface can lead to air inclusions despite the buffer pads. The same unevenness on the inside of the pipe can also encourage the accumulation of air bubbles in the water. Therefore, utmost care must be taken in selecting the installation site, adjusting the transducers, and mounting the sensor. If the acoustic aid does not provide satisfactory feedback, a slight shift of the sensor on the pipe and/or the transducer positions may help.

Operation of the Device

Communication with the Device

When the sensor is connected to the local Wi-Fi, its functions can be used via various communication methods (also in parallel):
  1. App on mobile phone, PC, tablet: You will not find the Aqua-Scope app in the app store of your mobile phone. We use a so-called PWA app (Progressive Web App, more at To do this, open the website in the system browser (Chrome@Android or Safari@iOS). You can use almost all functions of the app in the normal browser. After a short time, Android offers the option to install the app as a real app on the device. On iOS, a shortcut to the website must be placed on the desktop to receive push notifications if allowed.
  2. MQTT server: If configured accordingly, the sensor status information is sent to the configured MQTT server. The MQTT service must be activated and your own MQTT server/port/login must be stored in the device. Further information can be found in the Aqua-Scope Developers Manual.
  3. Own web service: Most smart home gateways enable the reception and display of sensor data via so-called 'webhooks' through plugins. Further information can be found in the Aqua-Scope Developers Manual.

Sensor Data and Notifications

The Aqua-Scope app displays: Furthermore, a whole series of alarm messages are displayed directly in the app, via email, and/or push notification. In the app, under "Configuration->Alarm Messages," you can set whether and how a particular alarm should be displayed and reported. In mains operation, alarms are also indicated directly on the device by red blinking of the LED and a sound.
An alarm can also be cleared directly on the device by pressing the button, even if the alarm condition has not disappeared. Otherwise, the alarm will be automatically reset when the alarm condition or the fault to be alarmed no longer occurs. Reset alarms are displayed in the app in the event history.

Alarm Messages and Their Causes

If a condition for an alarm occurs, the alarm is indicated locally on the device by red blinking and is transmitted via radio and displayed in the app. If the conditions for the alarm disappear, it is automatically cleared. An alarm can also be cleared directly on the device by pressing a button. The cleared alarm will not be triggered again for at least one hour, even if the alarm condition would require it. This prevents the alarm from being triggered again.


The device has a three-color LED (red/green/yellow) directly under the button on the top of the device. Different colors and blinking sequences indicate the operating states of the sensor.

Button Operation

Different commands can be triggered by pressing the button for varying lengths of time. After the button is pressed, the device beeps every second, allowing for easy estimation of the press duration.

Power Supply

The device can be powered either through an external USB-C power supply or by using two off-the-shelf AA batteries. Whenever an external power source is available, it will be used independently of the inserted batteries.

In battery operation, power consumption must be minimized, leading to the following changes:

All other functions of the device, such as leak detection, drip detection, etc., continue to operate.

Scope of Delivery

Technical Data - Part 1

Technical Data - Part 2 (MID/OIML-R49)

Support and Contact

Should you encounter any problem, please give us the opportunity to address it before returning this product. Please check our website and particularly the support section for answers and help. You can also send a message to

While the information in this manual has been compiled with great care, it may not be deemed an assurance of product characteristics. Aqua-Scope shall be liable only to the degree specified in the terms of sale and delivery. The reproduction and distribution of the documentation and software supplied with this product and the use of its contents is subject to written authorization from Aqua-Scope. We reserve the right to make any alterations that arise as the result of technical development.

Declaration of Conformity

Aqua-Scope Technology OÜ, Sakala 7-2, 10141 Tallinn, Republic of Estonia, declares that this radio emitting device works on the following frequences:

Български С настоящото Aqua-Scope Technology OÜ декларира, че този тип радиосъоръжение AQMWIE01 е в съответств ие с Директива 2014/53/ЕС. Цялостният текст на ЕС декларацията за съответствие може да се намери н а следния интернет адрес:

Čeština Tímto Aqua-Scope Technology OÜ prohlašuje, že typ rádiového zařízení AQMWIE01 je v souladu se směrnicí 2014/53/EU. Úplné znění EU prohlášení o shodě je k dispozici na této internetové adrese:

Dansk Hermed erklærer Aqua-Scope Technology OÜ, at radioudstyrstypen AQMWIE01 er i overensstemmelse med direktiv 2014/53/EU. EUoverensstemmelseserklæringens fulde tekst kan findes p følgende internetadresse:

Deutsch Hiermit erklärt Aqua-Scope Technology OÜ, dass der Funkanlagentyp AQMWIE01 der Richtlinie 2014/53/EU entspricht. Der vollständige Text der EU-Konformitätserklärung ist unter der folgenden Internetadresse verfügbar:

Eesti Käesolevaga deklareerib Aqua-Scope Technology OÜ, et kesolev raadioseadme tp AQMWIE01 vastab direktiivi 2014/53/EL nuetele. ELi vastavusdeklaratsiooni tielik tekst on kttesaadav jrgmisel internetiaadressil:

English Hereby, Aqua-Scope Technology OÜ declares that the radio equipment type AQMWIE01 is in compliance with Directive 2014/53/EU. The full text of the EU declaration of conformity is available at the following internet address:

Español Por la presente, Aqua-Scope Technology OÜ declara que el tipo de equipo radioeléctrico AQMWIE01 es conforme con la Directiva 2014/53/UE. El texto completo de la declaracin UE de conformidad está disponible en la direccin Internet siguiente:

Ελληνικά Με την παρούσα ο/η Aqua-Scope Technology OÜ, δηλώνει ότι ο ραδιοεξοπλισμός AQMWIE01 πληροί την οδηγία 2014/53/ΕΕ. Το πλήρες κείμενο της δήλωσης συμμόρ φωσης ΕΕ διατίθεται στην ακόλουθη ιστοσελίδα στο διαδίκτυο:

Français Le soussigné, Aqua-Scope Technology OÜ, déclare que l'équipement radioélectrique du type AQMWIE01 est conforme la directive 2014/53/UE. Le texte complet de la déclaration UE de conformité est disponible l'adresse internet suivante:

Hrvatski Aqua-Scope Technology OÜ ovime izjavljuje da je radijska oprema tipa AQMWIE01 u skladu s Direktivom 2014/53/EU. Cjeloviti tekst EU izjave o sukladnosti dostupan je na sljedećoj internetskoj adresi:

Italiano Il fabbricante, Aqua-Scope Technology OÜ, dichiara che il tipo di apparecchiatura radio AQMWIE01 conforme alla direttiva 2014/53/UE. Il testo completo della dichiarazione di conformit UE disponibile al seguente indirizzo Internet:

Latviešu Ar šo Aqua-Scope Technology OÜ deklarē, ka radioiekārta AQMWIE01 atbilst Direktīvai 2014/53/ES. Pilns ES atbilstības deklarācijas teksts ir pieejams šādā interneta v ietnē: Lietuvių Aš, Aqua-Scope Technology OÜ, patvirtinu, kad radijo įrenginių tipas AQMWIE01 atitinka Direktyvą 2014/53/ES. Visas ES atitikties deklaracijos tekstas prieinamas šiuo internet adresu:

Magyar Aqua-Scope Technology OÜ igazolja, hogy a AQMWIE01 típus rádiberendezés megfelel a 2014/53/EU irányelvnek. Az EUmegfelelőségi nyilatkozat teljes szövege elérhető a következő internetes címen:

Malti B'dan, Aqua-Scope Technology OÜ, niddikjara li dan it-tip ta' tagħmir tar-radju AQMWIE01 huwa konformi madDirettiva 2014/53/UE. It-test kollu tad-dikjarazzjoni ta' konformit tal-UE huwa disponibbli f'dan l-indirizz talInternet li ġej:

Nederlands Hierbij verklaar ik, Aqua-Scope Technology OÜ, dat het type radioapparatuur AQMWIE01 conform is met Richtlijn 2014/53/EU. De volledige tekst van de EUconformiteitsverklaring kan worden geraadpleegd op het volgende internetadres:

Polski Aqua-Scope Technology OÜ niniejszym oświadcza, że typ urządzenia radiowego AQMWIE01 jest zgodny z dyrektywą 2014/53/UE. Pełny tekst deklaracji zgodnośc I UE jest dostępny pod następującym adre sem internetowym:

Português O(a) abaixo assinado(a) Aqua-Scope Technology OÜ declara que o presente tipo de equipamento de rádio AQMWIE01 está em conformidade com a Diretiva 2014/53/UE. O texto integral da declarao de conformidade está disponível no seguinte endereo de Internet:

Română Prin prezenta Aqua-Scope Technology OÜ declară că tipul de echipamente AQMWIE01 este în conformitate cu Directiva 2014/53/UE. Textul integral al declarației UE de conformitate este disponibil la următoarea adresă internet:

Slovensko Aqua-Scope Technology OÜ potrjuje, da je tip radijske opreme AQMWIE01 skladen z irektivo 2014/53/EU. Celotno besedilo izjave EU o skladnosti je na voljo na naslednjem spletnem naslovu:

Slovensky Aqua-Scope Technology OÜ týmto vyhlasuje, že rádiové zariadenie typu AQMWIE01 je v slade so smernicou 2014/53/EÚ. Úplné EÚ vyhlásenie o zhode je k dispozícii na tejto internetovej adrese:

Soumi Aqua-Scope Technology OÜ vakuuttaa, että radiolaitetyyppi AQMWIE01 on direktiivin 2014/53/EU mukainen. EUvaatimustenmukaisuusvakuutuksen täysimittainen teksti on saatavilla seuraavassa internetosoitteessa:

Svenska Härmed försäkrar Aqua-Scope Technology OÜ att denna typ av radioutrustning AQMWIE01 verensstmmer med direktiv 2014/53/EU. Den fullständiga texten till EUförsäkran om verensstämmelse finns på följande webbadress:

Disposal Guidelines

Do not dispose of electrical appliances as unsorted municipal waste, use separate collection facilities. Contact your local government for information regarding the collection systems available. If electrical appliances are disposed of in landfills or dumps, hazardous substances can leak into the groundwater and get into the food chain, damaging health and well-being.