LiquiSonic® Sensor: Ultrasound in the middle of the circuit
A LiquiSonic sensor is used® Series designed to monitor coolant integrity without any maintenance. Two ultrasonic transducers are located at a fixed distance in the sensor head. The speed of sound results from the transit time of a pulse and the known measuring distance, and from this the temperature-compensated glycol content. The value is absolute, it is not tracked against a reference.
One fabric size, not a replacement size
Color, turbidity, inhibitor dye and conductivity do not change the measurement result. A physical property of the mixture itself is measured.
Temperature included
Each sensor records the media temperature with high precision and calculates its influence directly. Fluctuating flow temperatures do not shift the concentration value.
Gas bubbles are released
Gas in the medium changes the shape of the received signal. The sensor evaluates this and provides it as its own signal, regardless of the concentration.
Long distances between sensor and evaluation
The transmission is digital and carries up to 1,000 m. The controller can be in the technical room, even if the measuring point is far away.
What the operating staff sees on the device
The controller stands at the process and shows the status of the circuit without having to go through a control system. For trend recording, logbook and limit value management, it is also the point where everything comes together.
The main value without conversion
Concentration is big in the picture, in the unit in which your specification is written.
Allowed band as a bar
The scales on the left show how far concentration and temperature are from their limits without having to compare numbers.
Limit becomes action
If the concentration falls below the band or the gas proportion increases, this can be connected to a digital output and the countermeasure starts automatically.
The two typical events in trend
The concentration drifts away
Not a jump, but a drift: over a few hours the glycol content drops from 26.1 vol% to 23.0 vol% and falls below the minimum. A manual measurement during the service interval does not exactly match the intermediate values.
Possible causes: Make-up with pure water, extraneous water via a leaky heat exchanger, a different delivery batch.
Gas enters the circuit
The concentration remains at 26.1 vol%, while the gas content increases to 2.7 vol% within an hour and continues to fluctuate. The flow meter reports unchanged volume during this time.
Possible causes: incomplete ventilation after filling, work on quick couplings, outgassing at high flow temperatures.
Both curves come from the same measuring point. What differentiates them is the size that moves. One is the concentration, the other is the gas content, with the concentration remaining unchanged (schematic curves for illustration).
Two ways into the cooling circuit
Whether the sensor goes into the coolant distribution unit at the device manufacturer or is later placed in the existing pipeline does not change the measurement. It just changes who installs it and where the values go.
Ex works in the CDU
Two measuring points in the device, one in the flow of the facility circuit and one in the flow of the server circuit. The sensor reports to the existing CDU controller, there is no need for an additional operating device. We implement customer-specific housings, connections and interfaces even in small series.
Retrofitted in the pipeline
Sensor and controller are placed outside the device in the existing line. The easiest way to get started is at the filling and mixing skid: this is where the largest deviations occur and no productive circle needs to be touched.
Technical background
From running time to concentration
The speed of sound of a liquid is determined by its composition and temperature. For water-glycol mixtures the relationship is monotonous, so a measured value can be assigned to a glycol proportion. Common recipes for ethylene and propylene glycol are stored, and we will include others with your product name. Because the measuring section is mechanically fixed, the result does not drift.
Gas bubbles as a disturbance variable
Gas in the medium not only shifts the speed of sound, it changes the entire shape of the received signal. This evaluation runs parallel to the concentration measurement and is output as an additional signal. This shows that air is moving in the circuit, even if the flow meter continues to report volume inconspicuously.
Related sizes that are often meant
Density, Brix, conductivity or freezing point often appear in inquiries as synonyms for concentration. The glycol content can be determined directly from the ultrasound measurement and the freezing point can be derived from this. Density and conductivity values remain their own measurement variables with their own disruptive influences; they are not a replacement.
Economic benefit
✔ - Sampling and manual measurement are not necessary in regular operation
✔ - Coolant is replaced according to condition, not according to the calendar
✔ - No cleaning, no recalibration during operation
✔ - An avoided cooling failure pays for the investment
✔ - Frost protection and inhibitor protection remain detectable
✔ - Air entry is noticeable before pumps cavitate
✔ - Complete recording instead of random samples throughout the year
✔ - Documented release after filling and service
✔ - Provable compliance with the fluid specification
Designs, connections and design
Diving sensor with flange
Directly into pipe or container, in various installation lengths.
Process connections
From clamps and weld-in adapters to customer-specific flanges.
Components for OEMs
Sensor, electronics, and adapters newly combined to fit your device.
Practical examples and use cases
Availability is contractually guaranteed, and the coolant crosses the boundary to the customer. Continuous measurement turns a question of responsibility into a documented fact.
Cooling capacity, approach, and pressure drop are guaranteed, while the operator provides the fluid. As an installed measurement core, the sensor provides a basis for that commitment.
The project specification defines concentration and chemistry limits. On the fill and flush skid, the sensor verifies the initial fill and documents that it was maintained.
Brine and glycol circuits in production, food refrigeration, and heating networks: freeze protection remains verifiable, and refilling is monitored instead of estimated.