Switch Flow Transmitters
Last Updated: April 1, 2025
Description
Switch Flow Transmitters are devices designed to monitor and measure the flow of liquids or gases in a system. They provide a change in state, typically through a switch or relay, when the flow reaches a pre-established threshold, ensuring the proper function of the system by turning on or off as needed.
Working Principle
Switch Flow Transmitters operate by detecting changes in flow conditions and converting these into a switch action. They often use electro-mechanical components such as relays and reed switches to achieve this. The transmitter accepts inputs from sensors and transforms these into linear outputs, which can be used to monitor the flow rate and other variables. This functionality is crucial for maintaining system efficiency and preventing damage due to improper flow conditions.
Applications
Switch Flow Transmitters are used in a variety of industrial applications where precise flow monitoring is critical. For example, they are employed in chemical processing plants to ensure the correct flow of reactants, in HVAC systems to monitor coolant flow, and in water treatment facilities to regulate water distribution.
Advantages over other Flow Transmitters
Switch Flow Transmitters offer specific advantages, such as the ability to provide immediate feedback through a switch action, which can be crucial in systems requiring rapid response to flow changes. They are also versatile in terms of output options, supporting analog current, analog voltage, and frequency outputs, which can be advantageous in different industrial settings.
Limitations
One limitation of Switch Flow Transmitters is their reliance on mechanical components, which can be prone to wear and tear over time. This can lead to maintenance challenges and potential downtime if not properly managed. Additionally, they may not be suitable for applications requiring highly precise flow measurements, as their primary function is to detect threshold changes rather than provide continuous flow data.
Considerations
When considering Switch Flow Transmitters, it is important to evaluate initial costs, which can vary depending on the complexity and features of the device. Operating expenses should also be considered, particularly in terms of energy consumption and maintenance requirements. Durability is a key factor, as the mechanical components may require regular inspection and replacement to ensure continued accuracy and reliability. Additionally, the accuracy of these devices may not match that of more advanced flow measurement technologies, so they should be chosen based on the specific needs of the application.
from Fluid Components Intl. (FCI)
Mass Flow Meter Summary. The MT100 Series is an insertion type, multipoint thermal flow meter specifically designed for large diameter pipes, such as stacks and flues, and large rectangular ducts, such as air feed intakes and HVAC. These large pipe/duct applications are difficult for ordinary flow... [See More]
- Electrical Output: Current; Switch; Voltage
- Front Panel Interface: Digital Front Panel
- Interface Options: Serial/Digital; Network/Fieldbus
- Meter Type: Mass Flow Meter
from McCrometer, Inc.
The ProComm Max is the latest electronics available for our electromagnetic flow meters. It is a fully scalable solution that allows in-field upgrades to accommodate changes in power and communications protocols without missing a beat. The advanced design separates the converter and transmitter... [See More]
- Electrical Output: Switch; Voltage
- Process Media Type: Liquid
- Display: Digital
- Features: Built-in Alarm Indicator
from Sierra Instruments, Inc.
With its advanced mass flow sensor capabilities, the Compod ™ control valve, coupled with Sierra ’s SmartTrak ® 100 mass flow meters (MFM ’s) or controllers (MFC ’s) greatly simplifies air flow control systems and permits networking of multiple instruments using... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; RS-485/MODBUS RTU
- Front Panel Interface: Digital Front Panel (optional feature)
from McCrometer, Inc.
The ProComm Max is the latest electronics available for our electromagnetic flow meters. It is a fully scalable solution that allows in-field upgrades to accommodate changes in power and communications protocols without missing a beat. The advanced design separates the converter and transmitter... [See More]
- Electrical Output: Switch; Voltage
- Process Media Type: Liquid
- Display: Digital
- Features: Built-in Alarm Indicator
from Sierra Instruments, Inc.
Our Ultra High Purity 780S-UHP mass flow meter is the industry-choice for bulk gas distribution service in semiconductor fabs, in pharmaceutical production and other ultra-clean processes. Real-time monitoring of gas usage provides reliable information on consumption and usage patterns in the... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Modbus, Foundation Fieldbus, Profibus DP, HART, Pulse
- Front Panel Interface: Knobs/Switches; Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Steel-Mass ® 640S gas mass flow meters accurately monitor total gas mass flow rate of gases and insert easily into ducts and pipes up to 72-inches. Larger probe lengths are available upon request. Typical applications for gas mass flow meters include compressed air flow, aeration basin air flow,... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Modbus, Foundation Fieldbus, Profibus DP, HART
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Overview. The InnovaSwitch insertion-type level switch is a high-performance, industrial-grade liquid level indicator for tanks and process vessels. This product switches on level changes as small as 0.03 inch (0.8 mm) on dry-to-wet and wet-to-dry occurrences in a tank or vessel. The instrument was... [See More]
- Electrical Output: Current; Switch; Voltage
- Meter Technology: Mass; Thermal
- Meter Type: Mass Flow Meter; Velocity Flow Meter
- Velocity Flow Rate: 0.0100 to 500
from Sierra Instruments, Inc.
QuadraTherm ® 640i insertion gas mass flow meters from Sierra Instruments mark a breakthrough in thermal dispersion technology as the most accurate thermal mass flow meters on the market. Sierra's 640i, gas mass flow meters offer many benefits of immersible thermal mass flow technology... [See More]
- Electrical Output: Current; Switch
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Modbus, Foundation Fieldbus, Profibus DP, HART
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Boiler-Trak ™ 620S-BT insertion thermal mass flow meters provide an economical and easy-to-install boiler and heater efficiency solution for natural gas flow measurement applications. 620S-BT insertion thermal mass flow meters are also suited for compliance to new regulations for burning... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Pulse, Modbus
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Sierra was the first to introduce multivariable mass vortex flow meters to the market in the late 1990s with the InnovaMass "S-Series" product line-the 240S and 241S. The InnovaMass 241S inline version is a true workhorse in applications ranging from large pipes and ducts, to high pressure and... [See More]
- Electrical Output: Current; Switch
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus; BACnet Communications, HART, Modbus,, RS-485
- Front Panel Interface: Digital Front Panel (optional feature)
from Sierra Instruments, Inc.
Low Pressure Drop Flow Meters. SmartTrak 140 low pressure drop flow meters offers precision gas mass flow control of expensive process gases, where minimal pressure drop is a key consideration for cost savings and efficiency, the SmartTrak ® 140 low pressure drop flow meter controls up to 500... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital (optional feature); Network/Fieldbus; RS-232, RS-485 (optional), Profibus DP, Modbus, Foundation Fieldbus
- Front Panel Interface: Digital Front Panel (optional feature)
from Sierra Instruments, Inc.
Fast-Flo ® 620S insertion mass flow meters are the ideal mass flow meter for air and gases for light-industrial applications where a NEMA 4X (IP65) enclosure is acceptable. 620S mass flow meters have an accuracy is ± 1% of full scale, 0.2% of full scale repeatability, highly reliable 200... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Pulse, Modbus
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Sierra was the first to introduce multivariable mass vortex flow meters to the market in the late 1990s with the InnovaMass "S-Series" product line--the 240S and 241S. The InnovaMass 240S inline version is a true workhorse in applications ranging from large pipes and ducts, to high pressure and... [See More]
- Electrical Output: Current; Switch
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus; BACnet Communications, HART, Modbus,, RS-485
- Front Panel Interface: Digital Front Panel (optional feature)
from Sierra Instruments, Inc.
Thermal Mass Flow Meters - QuadraTherm ® 780i. QuadraTherm ® 780i inline thermal mass flow meters from Sierra Instruments offer the most accurate gas mass flow rate measurement on the market today, achieving gas mass flow rate accuracy never before possible, +/- 0.5% of reading above 50% of... [See More]
- Electrical Output: Current; Switch
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Modbus, Foundation Fieldbus, Profibus DP, HART
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
Flat-Trak 780S thermal mass flow meters offer improved measurement capabilities in installations where long straight pipe runs are not available. The 780S thermal mass flow meters incorporate Sierra ’s unique dual-plate flow conditioning element to eliminate velocity profile distortions as... [See More]
- Electrical Output: Current; Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital; Network/Fieldbus (optional feature); Pulse, Modbus, Foundation Fieldbus, Profibus DP, HART
- Front Panel Interface: Digital Front Panel (optional feature); Computer Controllable (optional feature)
from Sierra Instruments, Inc.
InnovaSonic 203 ultrasonic water flow meters are optimized for customers still looking for high performance, but needing a lower-cost, less feature-rich option for dedicated clamp-on ultrasonic metering. The 203 ultrasonic water flow meter is a digital liquid flow meter optimizes the measurement of... [See More]
- Electrical Output: Current; Frequency; Switch
- Display: Digital
- Interface Options: Serial/Digital; RS-232, RS-485, Modbus RTU
- Front Panel Interface: Digital Front Panel; Computer Controllable
from KOBOLD Instruments, Inc.
Product Features. Flow Range 1.6 to 110 GPH. Accurate Measurements for Lubricating Media. Economical Brass Construction. Accuracy ±1% Reading. The KOBOLD DRZ series rotary piston positive displacement flowmeter combines economy with high performance. The DRZ series is designed to measure any... [See More]
- Electrical Output: Current; Frequency; Switch; Voltage
- Front Panel Interface: Digital Front Panel (optional feature)
- Display: Digital (optional feature)
- Meter Type: Volumetric Flow Meter
from Brooks Instrument
Need reliable, durable flow measurement in high-pressure, high-temperature or hazardous process settings? The MT3750 metal tube variable area flow meter from Brooks Instrument is your hard-working answer. Constructed from high-strength steel, the MT3750 Series VA flow meter features a compact design... [See More]
- Electrical Output: Current; Switch
- Meter Technology: Rotameter; Variable Area
- Meter Type: Volumetric Flow Meter
- Gas Volumetric Flow Rate: 1.83
from E+E Elektronik
The EE741 in-line flow meter can be easily adapted for any measuring task. It is dedicated for accurate metering and monitoring of compressed air and technical gases in DN 15 to DN50 pipes. The thermal measuring principle and the well proven E+E hot film sensor element lead to best long-term... [See More]
- Electrical Output: Current; Frequency; Switch
- Display: Digital
- Interface Options: Serial/Digital; Network/Fieldbus
- Front Panel Interface: Digital Front Panel; Computer Controllable
from Malema Sensors
Tangential turbine flow meters continue to be the most common way to measure flow electronically in a wide range of industries. Enhancements to tangential turbine flow meter systems are producing a flow-sensing device that is smaller, easier to install, and more accurate than ever before. Malema... [See More]
- Electrical Output: Current; Switch; Voltage
- Meter Technology: Paddlewheel
- Meter Type: Volumetric Flow Meter
- Liquid Volumetric Flow Rate: 0.04 to 20.00
from OMEGA Engineering, Inc.
The FPR-200 series flowrate sensor integrates rugged tangential turbine technology with a precision digital-to-analog conversion circuit hermetically encapsulated within the body of the sensor. The flow sensor is ideal for measuring flowrates in cooling circuits, HVAC systems and batching... [See More]
- Electrical Output: Current; Switch
- Meter Technology: Velocity; Turbine
- Meter Type: Volumetric Flow Meter
- Liquid Volumetric Flow Rate: 0.50 to 50.00
from Teledyne Monitor Labs, Inc.
Building on the successful performance of the UltraFlow 100, Teledyne Monitor Labs has substantially improved and updated the design of our new UltraFlow 150. Our objective in our redesign was to further improve system accuracy, reliability and availability, while simplifying maintenance and user... [See More]
- Electrical Output: Switch; Voltage
- Display: Digital (optional feature)
- Interface Options: Serial/Digital
- Front Panel Interface: Digital Front Panel; Computer Controllable
from Clark Solutions
The model DS15 flow meters work according to the proven variable area principle. The float is moved upward in a tapered tube by the flowing medium and its upper edge indicates the flow rate by means of a scale affixed on to the measuring tube. By using a float with an integrated magnet, optional... [See More]
- Electrical Output: Current (optional feature); Switch
- Meter Type: Volumetric Flow Meter
- Display: Analog
- Meter Technology: Rotameter; Variable Area
from Invotec Solutions Ltd.
The Tracer Electronic Switching Flowmeter is designed for permanent installation to closely monitor water flow andtemperature conditions. Selectable analogue signal transmits 0 to 5 or 0 to 10 Volts; signal is scaleable for flow and temperature. The SPDT switch in the Tracer flow meter can be wired... [See More]
- Electrical Output: Switch
- Front Panel Interface: Digital Front Panel
- Display: Digital
- Meter Type: Volumetric Flow Meter
from KOBOLD Instruments, Inc.
Product Features. Suitable for many water-like liquids with max. 1% solids. High turndown ratio of 250 to 1. Very small pressure loss. Highly Repeatable. Measurement independent of density and temperature changes. The KOBOLD model DUK flowmeters are used for measuring, monitoring, and batching of... [See More]
- Electrical Output: Frequency; Switch; Voltage
- Front Panel Interface: Digital Front Panel
- Display: Digital
- Meter Type: Volumetric Flow Meter
from Brooks Instrument
Engineered to work where you need it: Choose the MT3809 variable area (VA) flow meter (rotameter) for all the high-pressure, high-temperature VA flow measurement and control requirements on your next project. Proven to deliver reliable, repeatable gas and liquid flow measurement and control in... [See More]
- Electrical Output: Current; Switch
- Display: Analog
- Interface Options: Network/Fieldbus
- Meter Type: Volumetric Flow Meter
from E+E Elektronik
The EE771 is a thermal mass flow meter for compressed air and gases. Irrespective of pressure and temperature, the EE771 flow meter registers mass flow, volumetric flow or standard flow. The flow meter can measure the consumption of compressed air, nitrogen, oxygen, CO2, argon or other non-corrosive... [See More]
- Electrical Output: Current; Frequency; Switch; Voltage
- Display: Digital
- Interface Options: Serial/Digital; Network/Fieldbus
- Front Panel Interface: Digital Front Panel
from Malema Sensors
The M-1800 series consists of an inline flow sensor and electronics in one package. The flow sensor is a straight-through PFA tube that uses ultrasonic sensing technology to measure the flow rate. The M-1800 utilizes the latest digital signal processing (DSP) technology and provides cost effective... [See More]
- Electrical Output: Current; Switch
- Meter Technology: Ultrasonic
- Meter Type: Volumetric Flow Meter
- Liquid Volumetric Flow Rate: 0.00 to 0.01
from OMEGA Engineering, Inc.
The FSW-9000 Series is a flow switch monitor that measures the velocity of the flow. It is ideal for use in measurement and control liquid applications. The FSW-9000 Series provides two output options: a 4 to 20mA analog output and a PNP/NPN output. For the 4 to 20 mA output, the electronics ’... [See More]
- Electrical Output: Current; Switch
- Velocity Flow Rate: 0.1312 to 6.56
- Meter Type: Velocity Flow Meter
- Accuracy: 5
from Clark Solutions
Series 1100 flow switches are manufactured to exacting standards and provide accurate flow detection for most applications. Product inspection involves calibrated tools and gages traceable to National Bureau of Standards. The flow swtches are broadly used in machine tools, HVAC equipment and any... [See More]
- Electrical Output: Switch
- Liquid Volumetric Flow Rate: 0.50
- Meter Type: Volumetric Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. No Features Available. The KOBOLD measuring instrument type DWD is a flow rate transmitter with digital indication of the actual flow rate, analogue outputand two adjustable all-or-nothing relays indicating the switching point for monitoring limit values. An RS232C serial interface... [See More]
- Electrical Output: Current; Switch; Voltage
- Front Panel Interface: Digital Front Panel
- Display: Digital
- Meter Type: Volumetric Flow Meter
from E+E Elektronik
The EE772 is a thermal mass flow meter for compressed air and gases. Irrespective of pressure and temperature, the EE772 flow meter registers mass flow, volumetric flow or standard flow. The flow meter can be used effectively to measure the consumption of compressed air, nitrogen, CO2 or other... [See More]
- Electrical Output: Current; Frequency; Switch; Voltage
- Meter Type: Mass Flow Meter
- Interface Options: Serial/Digital; Network/Fieldbus
- Meter Technology: Mass; Thermal
from Clark Solutions
Series 1800 flow switches are manufactured to exacting standards and provide accurate flow detection for most applications. Product inspection involves calibrated tools and gages traceable to National Bureau of Standards. Switch function involves magnet equipped PVC shuttle that is displaced at the... [See More]
- Electrical Output: Switch
- Liquid Volumetric Flow Rate: 0.50
- Meter Type: Volumetric Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. Adjustable Switch Point. Position-Independent Installation. Maximum Pressure 160 PSI/450 PSI. Adjustable Switching Point. Brass and SS Construction. Micro Switch. Maximum Media Temperature250 °F. KOBOLD FPS flow switches are used wherever reliable control for min. or max. [See More]
- Electrical Output: Switch
- Meter Technology: Velocity; Paddlewheel
- Meter Type: Volumetric Flow Meter
- Liquid Volumetric Flow Rate: 0.90 to 759.50
from E+E Elektronik
The EE776 is a thermal mass flow meter dedicated for monitoring compressed air, nitrogen, CO2 or other non-corrosive and non-flammable gases. It can be employed in pipes from DN50 to DN700 (2" to 28") and at up to 16 bar (232 psi). The EE776 flow meter set new standards in terms of safety and easy... [See More]
- Electrical Output: Current; Frequency; Switch; Voltage
- Front Panel Interface: Computer Controllable
- Interface Options: Serial/Digital; Network/Fieldbus
- Meter Type: Mass Flow Meter
from Clark Solutions
Series 2100 flow switches are manufactured to exacting standards and provide accurate flow detection for most applications. Product inspection involves calibrated tools and gages traceable to National Bureau of Standards. The switches function as a magnet embedded in a spring loaded polysulfone... [See More]
- Electrical Output: Switch
- Liquid Volumetric Flow Rate: 0.10
- Meter Type: Volumetric Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. Revolutionary Microprocessor-Based Drift Stabilization. NPT and 3-A Compliant Sanitary Fittings. No Moving Parts. Negligible Pressure Loss. Easy to Operate. Insensitive to Dirt. 4-20 mA Flow Rate Signal with KAL-A. The KAL-K thermal flow switch and KAL-A thermal flow sensor utilize... [See More]
- Electrical Output: Current; Switch
- Front Panel Interface: Digital Front Panel
- Display: Digital
- Meter Type: Volumetric Flow Meter
from Clark Solutions
Series 2600 flow switches are manufactured to exacting standards and provide accurate flow detection for most applications. Product inspection involves calibrated tools and gages traceable to National Bureau of Standards. Switch function involves magnet equipped PVC shuttle that is displaced at the... [See More]
- Electrical Output: Switch
- Liquid Volumetric Flow Rate: 0.50
- Meter Type: Volumetric Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. Bidirectional. Maximum Temperature 225 °F. Easy to Install. Low Cost. Low Pressure Drop. The extraordinary reliability of the KOBOLD paddle-type PPS flow switch is available at a competitive price and can be installed in pipes 1 â € and larger. These units, made of... [See More]
- Electrical Output: Switch
- Meter Technology: Velocity; Paddlewheel
- Meter Type: Velocity Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. Switch Point Adjustable. Easy to Install. Brass or SS Construction. Low Cost. Maximum Pressure1450/3600 PSI. KOBOLD paddle type flow switches can be used wherever a simple economic yet reliable monitoring instrument is required for flow switching applications. The device operates... [See More]
- Electrical Output: Switch
- Meter Technology: Velocity; Paddlewheel
- Meter Type: Velocity Flow Meter
- Process Media Type: Liquid
from KOBOLD Instruments, Inc.
Product Features. Widest Range of Wetted Materials Available in the Industry. Flow Tubes and Fittings Available in 316L Stainless Steel, Hastelloy C-22, Nickel Alloy, Monel, Tantalum, Gold Plate, Titanium and Inconnel. Others on Request. Liquid or Gas Flow Measurement. Extreme Pressure and... [See More]
- Electrical Output: Switch
- Meter Type: Mass Flow Meter
- Display: Digital
- Meter Technology: Mass; Coriolis