ST502 Insertion Type Ultrasonic Flowmeter
Ultrasonic flow meters that use transit-time methods to measure
flow.
Introduction
The ST502 Insertion-Type Ultrasonic Flow Meter utilizes advanced
digital signal processing technology to achieve ±0.5% high-accuracy
flow measurement across a wide range of pipe sizes and clean liquid
applications. Designed with a robust industrial-grade insertion
probe, the ST502 provides strong ultrasonic coupling directly
within the flow stream, ensuring excellent signal strength,
long-term stability, and dependable performance.
A clear, intuitive user interface and menu system allow for easy
configuration and operation. Unlike clamp-on models, the insertion
design positions the ultrasonic transducers directly inside the
pipe, enabling stronger signal penetration and enhanced
stability—particularly beneficial for large-diameter pipelines,
complex process conditions, or applications requiring highly
reliable and repeatable measurements.
Engineered for versatility, the ST502 is ideal for water
distribution systems, cooling loops, industrial process liquids,
energy monitoring, and HVAC applications. Its combination of high
accuracy, stable performance, and durable construction makes it a
dependable solution for long-term flow monitoring and critical
measurement tasks.
Benefits
- Measures the actual flow and total consumption of various liquids
- CNC machined process, magnetic open cover technology without any
screws.
- Adaptive signal processing algorithms optimize performance,
ensuring accurate measurements even in challenging flow conditions
- Clear display interface and LCD display with alarm function, easy
to operate and debug
- Utilize transit-time ultrasonic technology so as to realize
bidirectional flow measurement by precisely measuring the time it
takes for ultrasonic signals to transmit upstream and downstream
- Built-in 2G SD card and leverage storage capabilities to analyze
historical flow data to make system optimization.
- Built-in keypad and simple menu system for fast and easy option of
pipe diameter, pipe material, liquid type, and measurement units.
ST502 is a brand-new high-end product that is made of aluminum
alloy material and realizes CNC processing method. It adopts the
industry-leading full-sealed iron-absorbing side-opening technology
without any screw locking, and the tedious steps of screwing are
reduced. Such a convenient design truly realizes "one-second
opening".
Principle
The Transit-Time (TVT) Ultrasonic Flow Meter is a highly reliable
flow measurement technology widely used for clean liguids. Unlike
clamp-on designs, the insertion-type meter places the ultrasonic
transducers directly into the pipe wall so they make contact with
the fluid. This ensures strong ultrasonic transmission, excellent
signal quality, and stable long-term performance, especially on
large or thick-walled pipes.
In an insertion-type TVT flow meter, two ultrasonic transducers are
inserted into the pipe wall. One transducer transmits a pulse
downstream (T_down) with the direction of the fluid, while the
other transmits upstream (T_up) against the flow. Because the
flowing liquid accelerates the downstream signal and slows the
upstream signal, the time difference (Δt=T_up - T_down) is
proportional to the flow velocity.
Specifications
| Performance specifications |
| Velocity range | 0.03 ~ ±40ft/s (0.01 ~ ±12m/s) |
| Accuracy | ±0.5% |
| Pipe size | 1’’~200’’ (25mm~5000mm) |
| Repeatability | 0.15% of measured value |
| Linerarity | ±1.0% |
| Fluid | Water, Sea water, Oil, Alcohol... |
| Pipe material | PVC, stainless steel, carbon steel, copper... |
| Function specifications |
| Communication & Outputs | Communication: ModBus RS485 |
| Analog output: 4~20mA, max load 750Ω. |
| Pulse output: 0~9999Hz, OCT, (min. and max. frequency is
adjustable) |
| Relay output: max 1Hz(1A@125V AC or 2A@30V DC) |
| Flow Unit | Cubic Meters(m³), Liters(l), USA Gallons(gal). The factory default
unit is m3/h. |
| Time Unit | /Day/Hour, /Min, /Sec. |
| SD Card | Max record: 2GB, working more than 1000 days |
| Storage time interval: 1~86400s |
| Power supply | 24V DC/1A@ max |
| Keypad | 16 touch keys |
| Display | 20×2 lattice alphanumeric, back lit LCD. |
| Temperature | Transmitter: -40℉~140℉ (-40℃~60℃) |
| Transducer: -40℉~176℉ (-40℃~80℃) |
| Humidity | Up to 99% RH, non-condensing |
| Physical specifications |
| Transmitter | Die-cast aluminum, IP65, CNC machined |
| Transducer | Encapsulated design, protection grade IP68 |
| Transducer cable | Standard cable length: 33ft (10m). |
| Weight | Transmitter: 1kg |
Product Dimension
| Transmitter |
 |
| Transducer |
 |
Product Display
Communication and Output Functions
The ST502 Fixed Ultrasonic Flow Meter is equipped with multiple
communication and output options to ensure seamless integration
into various industrial control systems. These outputs enable
real-time data acquisition, remote monitoring, and control of
flow-related processes.
Summary of Output Capabilities
| Output Type | Function | Application Examples |
| RS485(Modbus) | Digital communication | Remote monitoring, SCADA, system integration |
| 4-20mA | Analog input Analog output | PLC input, process feedback, DCS systems |
| OCT Pulse | Flow totalization output | Batch controllers, energy meters, flow loggers |
| Relay | Alarm/control output | Trigger alarmscontrol valves/pumps, flow safety protection |
Wiring Diagram & Installation Methods
