When selecting a solution for level measurement, the comparison between radar level gauges and ultrasonic level gauges often becomes a focal point. If attention is paid to the anti-interference capability of radar level measuring instruments, the stability of data transmission for radar remote level gauges, and maintenance costs, it is necessary to make a comprehensive judgment based on working conditions, medium characteristics, and installation conditions.

For scenarios such as chemicals, water treatment, storage tanks, silos, food, and pharmaceuticals, level measurement is not simply about “being able to measure,” but about achieving a balance among accuracy, stability, response speed, maintenance frequency, and total cost of use. Many purchasing personnel place radar and ultrasonic in the same comparison chart during the initial selection stage, but what truly determines success or failure is often steam, foam, dust, agitation, installation dead zones, and on-site temperature and pressure fluctuations.

As a specialized high-tech enterprise in the field of sensors and instrumentation, Xi’an Shenghongchuang Instrumentation Co., Ltd. has long provided product solutions centered on industrial measurement scenarios, including pressure, displacement, flow, weighing, force measurement, temperature and humidity, and intelligent digital display control instruments. In the supporting selection of level measurement solutions, what enterprise users care more about is: which solution is more reliable, more suitable for the specific working condition, and more conducive to later-stage remote transmission and system linkage. The following analysis will be carried out from several aspects, including principles, scenarios, parameters, and procurement implementation.

Core Differences Between Radar Level Gauges and Ultrasonic Level Gauges

Radar level gauges rely on electromagnetic wave reflection for measurement, with common frequency bands including 6GHz, 26GHz, 80GHz, etc.; ultrasonic level gauges calculate level through the propagation of sound waves in air and the echo return time. Both are non-contact measurement methods, but the different transmission media lead to very obvious differences in stability under complex working conditions.

Simply put, ultrasonic depends more heavily on the air environment, and temperature, humidity, steam, and airflow all affect sound velocity and echo quality; radar is relatively less affected by air conditions and is more suitable for environments with heavy dust, condensation, mild steam, or large temperature differences. Therefore, when there are more than 2 interference factors on site, radar is usually more likely to obtain a continuous and stable data curve.

But this does not mean that ultrasonic has no value. For applications such as normal temperature and pressure, open water pools, sewage wells, and rainwater pools, with measuring ranges between 3m–15m, relatively limited budgets, and fairly regular installation environments, ultrasonic remains a highly cost-effective choice. The key is not “which is more advanced,” but “which is a better match.”

Common Differences in Field Performance Between the Two Technologies

In closed tanks, if the foam layer thickness on the medium surface reaches more than 30mm, ultrasonic may experience echo attenuation; while radar generally has better adaptability to foam in most liquid media. If the dust concentration inside the silo is high and there is discharge impact, 80GHz high-frequency radar has a greater advantage in narrow beam focusing and can reduce false echoes from silo walls and structural components.

In terms of installation, ultrasonic usually requires an unobstructed sound path below the sensor to avoid interference from crossbeams, ladders, and feed inlets; although radar also needs to avoid strongly reflective structures, through beam angle control and echo learning, it usually has stronger adaptability to complex installation positions. For tanks with a height of more than 10m, radar solutions are often more stable.

To make a more intuitive preliminary judgment, you can first look at the comparison table below.

From the comparison results, if the project goal is to improve anti-interference capability and long-term operating stability, radar level gauges are usually the more reliable option; if the on-site working conditions are simple, the budget is limited, and the range is moderate, ultrasonic still has relatively high application value. The first step in selection is not to look at price first, but to first determine whether there are obvious interference sources on site.

Which Working Conditions Are More Suitable for Radar, and Which Scenarios Make Ultrasonic More Economical

In industrial sites, more than 60% of level measurement failures do not come from the instrument itself, but from incomplete identification of working conditions. If medium characteristics, tank structure, installation position, and linkage systems are not clearly sorted out before procurement, then even if the brand is replaced later, problems such as repeated false alarms, fluctuations, and excessively large dead zones may still occur.

Generally speaking, the following working conditions are more recommended for prioritizing radar level measuring instruments: closed storage tanks, stirred tanks, slightly pressurized vessels, the presence of steam or condensation, heavy dust in silos, obvious level fluctuations, ranges exceeding 8m, and requirements for stable remote transmission. Such scenarios value continuity and anti-interference more, rather than merely obtaining a one-time measurable result.

Ultrasonic is more suitable for projects such as open pools, clean water tanks, sewage lift wells, environments without obvious steam, regular installation spaces, and medium measuring distances. If the liquid surface is relatively stable, on-site temperature changes are small, and wind speed is low, ultrasonic can complete level monitoring tasks with lower investment, making it especially suitable for cost-sensitive retrofit projects.

Selection Recommendations by Scenario

• Chemical storage tanks: prioritize dielectric constant, steam, agitation, and corrosion protection requirements; radar is usually more stable.
• Sewage pools and regulating tanks: if it is an open environment with a range of 5m–10m, ultrasonic offers better cost efficiency.
• Solid material silos: when discharge impact, dust, and wall buildup are obvious, high-frequency radar is recommended.
• Food or pharmaceutical storage tanks: focus on hygienic structure, condensation, and cleaning conditions, and radar compatibility should preferably be evaluated first.

4 Signals for Determining Whether “Radar Is a Must”

If more than 2 of the following 4 conditions occur simultaneously on site, it is usually recommended to directly proceed with radar solution evaluation: first, there is steam or temperature-difference condensation inside the tank; second, the range exceeds 10m; third, the liquid surface has foam, fluctuations, or agitation; fourth, long-term connection to PLC, DCS, or remote monitoring platforms is required while maintaining stable transmission.

For remote transmission projects, in addition to the measurement principle, signal output is also critical. Common interfaces include 4-20mA, RS485, Modbus, etc. If more than 10 level instruments are connected simultaneously in one system, communication stability, wiring standards, and electromagnetic interference suppression directly affect data reliability, rather than being merely a sensor range issue.

The table below can help purchasing personnel quickly determine priorities according to working conditions.

In actual projects, many companies ultimately adopt a combined approach of “using radar in key tank areas and ultrasonic in ordinary pools.” This can ensure the stability of critical positions while also taking the overall budget into account. For multi-point projects, tiered configuration is often more reliable than full coverage with a single technology.

Key Parameters and Implementation Details to Verify During Procurement

Level gauge selection is not just about looking at the two figures of “range” and “price.” What truly affects delivery results includes at least 6 dimensions: range, dead zone, medium characteristics, process temperature, process pressure, and installation connection. At the same time, it is also necessary to confirm output signal, power supply method, protection rating, and whether local display and remote communication are required.

For example, for the same 12m storage tank, if the top installation space is limited, there are crossbeams inside, and the medium surface fluctuates frequently, then the instrument beam angle and dead zone parameters are more important than the “theoretical maximum range.” If it is an outdoor working condition, at least common protection grades such as IP65 and IP67 should be considered; if there is corrosive medium, it is also necessary to check whether the antenna or probe material is compatible.

In remote transmission applications, 4-20mA is suitable for point-to-point connection, while RS485 is suitable for multi-node networking. For plant automation upgrade projects, it is recommended to clarify the communication protocol, control cabinet interface, cable length, and grounding method at an early stage. Many problems that appear to be “level fluctuations” are ultimately traced back to wiring, shielding, and power supply fluctuations, rather than the measurement principle itself.

5 On-Site Confirmations Recommended Before Selection

1. Confirm the medium type, whether it is liquid, slurry, or powder, and record whether there is foam, volatilization, and wall buildup.
2. Confirm the range, installation height, and minimum level position to avoid the dead zone affecting effective measurement.
3. Confirm the tank structure and check whether there are agitators, heating coils, feed inlets, and crossbeams.
4. Confirm environmental conditions, including temperature, humidity, dust, steam, corrosion, and explosion-proof requirements.
5. Confirm system requirements and clarify whether 24V power supply, 4-20mA output, or RS485 communication is required.

Common Misunderstanding: Only Pursuing High Accuracy While Neglecting Long-Term Stability

For most industrial level scenarios, the procurement goal is not laboratory-grade accuracy, but stable operation for more than 12 months while keeping maintenance frequency within a reasonable range. If an instrument claims excellent accuracy but requires frequent recalibration or probe cleaning after just 2 months, its overall cost is not low. B2B projects should pay more attention to life-cycle cost rather than one-time purchase price.

Xi’an Shenghongchuang Instrumentation Co., Ltd. has long served industrial measurement and control scenarios and can coordinate considerations from sensor matching and signal acquisition to intelligent digital display control instrument linkage. This integrated approach is very important for project implementation, because level data ultimately often does not exist independently, but needs to work together with alarms, displays, pump and valve control, and production management systems.

From Maintenance Cost and Delivery Efficiency to System Linkage, How to Make a More Reliable Choice

When purchasing level gauges, companies cannot compare only the unit price of the equipment, but must also compare installation difficulty, commissioning time, downtime risk, and follow-up maintenance frequency. For 1 device, the difference may not be obvious; but when the project scale reaches 10 units, 20 units, or even more, the gap in which solution is more worry-free will quickly widen.

If the project goal is “short-term usability,” ultrasonic can be deployed faster in some open scenarios; if the goal is “long-term stability, less maintenance, and suitability for integration into control systems,” radar remote level gauges usually have greater advantages. Especially in scenarios requiring year-round continuous operation and where the desired frequency of manual on-site inspection is reduced to no more than 1 time per month, radar solutions are more likely to meet management requirements.

From an implementation perspective, it is recommended to divide the project into 3 stages: early working condition confirmation, mid-stage installation and commissioning, and later-stage linkage verification. Spending 1–2 days in the early stage to fully collect working condition data can often reduce about 70% of subsequent rework communication. For industrial projects, accurate selection is more important than replacement speed.

4 Dimensions for Procurement Decision-Making Reference

First, look at the complexity of the working conditions; second, look at system linkage requirements; third, look at full life-cycle maintenance cost; fourth, look at whether the supplier can provide technical support from sensors to instrumentation matching. Especially in scenarios where data such as pressure, flow, temperature and humidity, and weighing need to be collected together, compatibility among instruments and engineering support capabilities are even more critical.

The following table can serve as a simplified decision-making framework during procurement communication.

If the company is currently advancing automation upgrades, it is recommended to evaluate level, pressure, flow, and display control links under the same measurement logic. This not only helps reduce interface mismatch problems, but also facilitates later maintenance. For users who need customized measurement and control solutions, communicating early with suppliers experienced in multiple categories of sensors will be more effective than simply comparing prices.

Frequently Asked Questions and Final Selection Recommendations

When selecting a level measurement solution, does a higher price mean greater reliability?

Not necessarily. If the site is a normal-temperature open pool with a range of only 4m–5m, choosing a more complex solution may not be cost-effective. The real standard of reliability is whether the equipment can operate continuously for 6–12 months after being matched with the working condition, with stable signal output and controllable maintenance burden, rather than simply looking at whether the purchase price is high or low.

Can ultrasonic level gauges be used in remote transmission systems?

Yes, but the premise is that environmental interference is limited, wiring is standardized, power supply is stable, and the output signal is confirmed to be compatible with the control system. If the project has high requirements for the continuity of remote level data, such as needing to connect to PLC, DCS, or cloud platforms for trend analysis, it is recommended to prioritize evaluating the stability performance of radar remote level gauges.

What Is Most Easily Overlooked During Procurement?

What is most easily overlooked is the impact of installation conditions and on-site structural components. Many projects provide only the range and medium name, but do not explain the position of the flange port, internal crossbeams of the tank, feed inlets, agitators, and inspection port distribution, resulting in a large number of false echoes during commissioning. It is recommended to provide at least 4 types of information: medium, range, structural drawing, and signal requirements.

Final Recommendation: Classify Working Conditions First, Then Set Priorities

If the project working conditions are complex, with a focus on low maintenance, strong anti-interference, and stable remote transmission, radar level gauges are usually the more reliable choice; if the working conditions are simple, the budget is limited, and the focus is on basic monitoring, ultrasonic is still a practical solution. For multi-point projects, it is recommended to carry out A, B, and C tiered configuration according to criticality, prioritizing resources for high-risk positions.

Xi’an Shenghongchuang Instrumentation Co., Ltd. can combine industrial measurement scenarios to provide enterprise users with sensor and instrument matching ideas that are closer to on-site needs. If you are evaluating a level measurement solution, or need coordinated design with pressure, flow, temperature and humidity, and display control systems, welcome to contact us immediately to obtain customized solutions, consult product details, and learn about more solutions.