The medium of the liquid cooling system is mostly deionized water, ethylene glycol coolant, and fluorinated liquid. Due to the perennial low-temperature circulation, water hammer impact on pipelines, and humid condensation environment, the preferred selection is a transmitter with 316L wetted material, diffused silicon core, high overload resistance, and condensation-resistant seal. The Longlu PTL516 is the mainstream model suitable for liquid cooling measurement.

I. Strict selection requirements for transmitters under liquid cooling conditions

    Medium corrosion resistance: The cooling liquid is added with corrosion inhibitors and antifreeze additives. Ordinary iron diaphragms are prone to rusting and leakage, so a fully stainless steel liquid-contact structure is necessary to prevent the medium from corroding the diaphragm and causing drift or leakage.

    Resistance to water hammer and instantaneous high pressure: The start-stop of water pumps and the opening and closing of valves generate instantaneous impact pressure. The transmitter requires sufficient overload margin to avoid damage to the core due to instantaneous overpressure.

    Resistance to low temperature and condensation environment: Liquid-cooled equipment rooms experience low temperatures and high humidity, making the equipment prone to condensation and water ingress. The overall sealing and protection level of the equipment must not be lower than IP65 to prevent moisture from infiltrating and causing circuit board malfunctions.

    Long-term continuous stability: Data centers and energy storage devices require liquid cooling for 24/7 uninterrupted operation, with low zero drift and reduced frequency of periodic on-site calibration.

    Signal adaptation and automatic control system: Equipped with industrial standard output signals as standard, it can be directly connected to PLC, dynamic environmental monitoring, and liquid cooling control cabinets to achieve remote pressure acquisition and interlock regulation.

II. Product Advantages of Longlv PTL516 Adapted to Liquid Cooling

    The liquid-contacting structure is compatible with cooling liquids: the entire machine is made of 316 stainless steel, with integrated laser sealing welding, resistant to corrosion from most liquid cooling media such as ethylene glycol, deionized water, and fluorinated liquids. This fundamentally prevents media erosion failures and is suitable for server liquid cooling, energy storage temperature control, and industrial equipment water cooling across all scenarios.

    Shock and overload resistance design: The diffused silicon core body comes with excellent shock resistance, easily resolving the instantaneous high pressure caused by water hammer in liquid cooling pipelines. It is suitable for installation at pressure fluctuation points such as pump inlets and outlets, CDU chillers, and plate heat exchangers.

    Sealed and moisture-proof design suitable for condensation environments: The enclosure features a sealed and protective design, effectively isolating it from condensation and water vapor splashes in the machine room. The internal circuitry remains unaffected by moisture in low-temperature conditions, ensuring stable measurement values without any fluctuations in perennial low-temperature environments.

    High-precision long-term operation: The diffusion silicon sensing solution features small temperature drift and low annual drift, meeting the requirements of uninterrupted operation throughout the year for liquid cooling. It eliminates the need for frequent disassembly and calibration, significantly reducing subsequent operation and maintenance costs.

    Flexible output and easy networking: Conventional 4-20mA analog signal, with optional digital communication output, allowing easy integration into liquid cooling automation control systems. It enables real-time monitoring of supply and return pipeline pressure, and predicts pipeline blockages and medium leaks through pressure changes.

    The integrated temperature and pressure model is more convenient: the PTL516W integrated temperature and pressure model from the same series, with single-hole installation for simultaneous pressure + coolant temperature collection, reduces the number of pipeline openings and minimizes the risk of leakage in the liquid cooling system, making it the preferred choice for precise monitoring in large-scale cooling stations.

III. Selection schemes for different liquid cooling scenarios

    For standalone water cooling of small equipment (such as machine tools and lasers), the standard model PTL516 is recommended. It should be installed at the outlet of the circulating pump and the water tank pipeline to monitor the system's operating static pressure and abnormal pressure rise.

    Centralized liquid cooling for data centers and computer rooms: The main choice is PTL516, with transmitters installed before and after the filter to monitor pressure difference. An increase in pressure difference can provide early warning of filter blockage; key cold plate entrances and exits are equipped with measuring points to ensure stable pressure in the cooling pipeline.

    Energy storage battery pack liquid cooling system: Preferably, the integrated temperature and pressure sensor PTL516W is used, which can simultaneously measure temperature and pressure, precisely control the operating conditions of the battery cooling circuit, and automatically activate and deactivate the control system for overpressure and overtemperature protection.