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Standard and Specialist Flow Sensors & Switches
Gems Sensors

Standard and Specialist Flow Sensors & Switches

We supply four types of flow sensor from Gems for the continual measurement of gases and liquids. 
Piston types for low flow rates and shuttle models for high flow rates with fixed set points, paddle models for large line sizes and electronic switches 
  • High-quality, corrosion-resistant materials
  • Repeatable performance at low flows
Gems Sensors & Controls has a strong reputation for collaborating with in-house engineering teams, bringing a detailed understanding of the design and operational factors involved with each application.

Often, the choice of sensor is dictated by the media to be measured, such as its specific gravity, viscosity or corrosiveness. Sometimes, design constraints relate to the best way to integrate the sensor, including its position, mounting and size within a restricted space.
Low Flow Rate Turbine Sensors
Ultra-compact TurboFlow® from Gems are low flow rate sensors that provide continual measurement from 0.1 to 8 GPM (0.5 to 30 lpm). Their Hall-effect sensor delivers accuracy to ±3 % of reading and 0.5 % repeatability. Lightweight, these sensors can be mounted in any position.
FT-110 Series TurboFlow Sensor

FT-110 Series TurboFlow Sensor

Economical Hall Effect flow-rate sensor with a high level of accuracy, capable of measuring low liquid flow rates of 0.1 to 8 GPM

OPEN FT110 DATASHEET

FT-110M Series TurboFlow Sensor

FT-110M Series TurboFlow Sensor

Economical Hall Effect flow-rate sensor with a brass design for robust applications, capable of measuring low liquid flow rates of 0.53 to 6.6 GPM
OPEN FT110M DATASHEET

FT-210 Series TurboFlow Sensor

FT-210 Series TurboFlow Sensor

Low flow Hall Effect turbine sensor capable of measuring flow rates from 0.1 to 2.5 LPM. Fast reaction to on/off dispensing applications. 

OPEN FT210 DATASHEET

FT-330 Series Turbine Flow Sensor

FT-330 Series Turbine Flow Sensor

Highly accurate and repeatable Hall Effect turbine flow sensor, capable of measuring low flow rates from 0.2 to 4 GPM. NSF certified so ideal for water or beverage dispensing applications
OPEN FT330 DATASHEET

Piston-Type Inline Flow Switches
The FS-380P series of piston type flow switches is designed for low liquid flow rates (0.25 to 2.0 GPM). The FS-380 series of piston type flow switches is designed for low liquid flow rates (0.15 to 2 GPM) and high-pressure applications such as industrial cleaning equipment. Made from brass or stainless steel, each compact and robust switch provides a simple design and reliable operation.  
Low Liquid 0.07 to 2.00 GPM Flow Setting

Low Liquid 0.07 to 2.00 GPM Flow Setting

Polypropylene with 3/8" NPT Male (or 1/4" QDC Male) connection


OPEN FS-380P DATASHEET
High Pressure  Low Liquid 0.15 to 2.00 GPM Flow Setting

High Pressure 
Low Liquid 0.15 to 2.00 GPM Flow Setting  

Available in robust brass or stainless steel. Suitable for water applications, such as industrial cleaning equipment.  
OPEN FS-380 DATASHEET
Shuttle Type Low Cost Flow Switches
Shuttle-type flow switches are designed for moderate to high flow rates. 
Shuttle Flow Switch For Threaded Plastic Piping

For Threaded Plastic Piping

Low cost, polypropylene shuttle type switch. FDA/NSF approved. Flow rate settings: 0.25 GPM to 5.0 GPM


OPEN FS500 DATASHEET
Shuttle General Purpose Straight-Through Flow Path

General Purpose Straight-Through Flow Path 

Durable and accurate flow switches in bronze or stainless steel. Available as fixed or adjustable. Ideal for improper flow rates in high volume lubrication, cooling or process systems
OPEN FS-200 DATASHEET
OPEN FS-400 DATASHEET
Shuttle Flow Switch For Plastic Piping

For Plastic Piping

Low cost corrosion-resistant PVC fixed flow switch with a flow rate of 0.5 GPM or 2.0 GPM



OPEN FS-440P DATASHEET
Shuttle Paddle Wheel Flow Sensors RotorFlow

Paddle Wheel Flow Sensors RotorFlow® 

Highly visible design offers accurate visual indication, flow rate sensing and switching. Available with brass, stainless steel or hydrolytically-stable polypropylene housings. 
OPEN ROTORFLOW DATASHEET
Other Piston Type Flow Switches
Piston-type flow switches are designed for low flow rates. Available in a variety of types to suit specific pressure applications or design parameters
Molded Plastic Flow Switch for Industrial Applications

Molded Plastic for Industrial Applications

Economical Ryton® fixed flow switch for flow rate between 0.1 GPM to 1.5 GPM



OPEN FS-4 DATASHEET
Straight-Through Flow Path Flow Switch for Industrial Applications

Straight-Through Flow Path for Industrial Applications

Economical flow switch with pre-adjusted set points, used in photocopiers, heavy-duty floor cleaners and industrial dishwashers


OPEN FS-6 DATASHEET

Straight Flow Path Flow Switch with Low Pressure Drop

Straight Flow Path with Low Pressure Drop

Slim polypropylene fixed flow switch for flow rate between 0.5 GPM to 5 GPM. Used to reduce pressure drop to a minimum. 


OPEN FS-150 DATASHEET

Miniature Brass Piston Flow Switch

Miniature Brass

Compact fixed flow switch for tight instrumentation packages for flow rate between 0.10 GPM to 1.50 GPM. 
Designed for use with water and oil, these switches are suitable for high volume OEM applications.
OPEN FS-927 DATASHEET

Precision-Calibrated General Purpose Piston Flow Switch

Precision-Calibrated General Purpose

Constructed from brass or stainless steel, fixed flow switch suitable for liquids and gases, factory preset for actuation at specified flow rates.
OPEN FS-925 DATASHEET
Precision-Calibrated Low Flow Piston Flow Switch

Precision-Calibrated Low Flow

Constructed from brass or stainless steel, fixed flow switch suitable for liquids and gases, factory preset for actuation at specified flow rates.
OPEN FS-926 DATASHEET
General Purpose Straight-Through Path Piston Flow Switch

General Purpose Straight-Through Path

Fixed or adjustable explosion-proof flow switch with a durable construction ideal for detecting improper flow rates in high volume lubrication, cooling or process systems
OPEN FS-200 DATASHEET
Oil Flow Monitoring with Viscosity Compensation Piston Flow Switch

Oil Flow Monitoring with Viscosity Compensation

Fixed pre-set explosion-proof oil flow switch. Compensates for viscosity changes in fluid automatically.

OPEN FS-930 DATASHEET
Tools & resources
Advantages of Gems flow sensors and switches
An Wide Range of Task Dedicated Items
Gems Sensors features a very wide range of sensors and switches, each dedicated to a specific role.
Long-Life Products
Gems Sensors' products are constructed from highly corrosion resistant materials intended to endure heavy wear and tear.
Tailor Made Items
Gems' flow switches are built to have fixed or adjustable actuation settings, giving them the ability to be fitted to practically every use.
Accurate Information Feedback
Gems' turbine flow sensors are renowned for their high accuracy for liquid monitoring, along with fast-reaction emergency shutdown systems.

Specifying the Right Switch

We colloborate with in-house engineering teams to identify the most effective solution for your application, helping you to select the best fit from hundreds of models available
Hawco Gems Flow Sensors & Switches
Hawco Gems Flow Sensors & Switches

Reliable supply chain

We offer inventory support to help maintain stock levels and reduce time-to-market for new products. 
Here to support you

Discuss your application

We would like to understand your project scope to help specify the right flow sensor for your product. Call +44 (0)1483 869 070 or email sales@hawco.co.uk

Got a technical question?

We can provide detailed information about any Gems product and recommend whether it is right for your requirements. 

Special requirements

With a wide choice of construction materials, mounting types and electrical termination, we can suggest customised solutions. Contact us on +44 (0)1483 869070 or email sales@hawco.co.uk.
Standard and Specialist Flow Sensors & Switches
Gems Sensors

Standard and Specialist Flow Sensors & Switches

We supply four types of flow sensor from Gems for the continual measurement of gases and liquids. 
Piston types for low flow rates and shuttle models for high flow rates with fixed set points, paddle models for large line sizes and electronic switches 
  • High-quality, corrosion-resistant materials
  • Repeatable performance at low flows
Gems Sensors & Controls has a strong reputation for collaborating with in-house engineering teams, bringing a detailed understanding of the design and operational factors involved with each application.

Often, the choice of sensor is dictated by the media to be measured, such as its specific gravity, viscosity or corrosiveness. Sometimes, design constraints relate to the best way to integrate the sensor, including its position, mounting and size within a restricted space.
Low Flow Rate Turbine Sensors
Ultra-compact TurboFlow® from Gems are low flow rate sensors that provide continual measurement from 0.1 to 8 GPM (0.5 to 30 lpm). Their Hall-effect sensor delivers accuracy to ±3 % of reading and 0.5 % repeatability. Lightweight, these sensors can be mounted in any position.
FT-110 Series TurboFlow Sensor

FT-110 Series TurboFlow Sensor

Economical Hall Effect flow-rate sensor with a high level of accuracy, capable of measuring low liquid flow rates of 0.1 to 8 GPM

OPEN FT110 DATASHEET

FT-110M Series TurboFlow Sensor

FT-110M Series TurboFlow Sensor

Economical Hall Effect flow-rate sensor with a brass design for robust applications, capable of measuring low liquid flow rates of 0.53 to 6.6 GPM
OPEN FT110M DATASHEET

FT-210 Series TurboFlow Sensor

FT-210 Series TurboFlow Sensor

Low flow Hall Effect turbine sensor capable of measuring flow rates from 0.1 to 2.5 LPM. Fast reaction to on/off dispensing applications. 

OPEN FT210 DATASHEET

FT-330 Series Turbine Flow Sensor

FT-330 Series Turbine Flow Sensor

Highly accurate and repeatable Hall Effect turbine flow sensor, capable of measuring low flow rates from 0.2 to 4 GPM. NSF certified so ideal for water or beverage dispensing applications
OPEN FT330 DATASHEET

Piston-Type Inline Flow Switches
The FS-380P series of piston type flow switches is designed for low liquid flow rates (0.25 to 2.0 GPM). The FS-380 series of piston type flow switches is designed for low liquid flow rates (0.15 to 2 GPM) and high-pressure applications such as industrial cleaning equipment. Made from brass or stainless steel, each compact and robust switch provides a simple design and reliable operation.  
Low Liquid 0.07 to 2.00 GPM Flow Setting

Low Liquid 0.07 to 2.00 GPM Flow Setting

Polypropylene with 3/8" NPT Male (or 1/4" QDC Male) connection


OPEN FS-380P DATASHEET
High Pressure  Low Liquid 0.15 to 2.00 GPM Flow Setting

High Pressure 
Low Liquid 0.15 to 2.00 GPM Flow Setting  

Available in robust brass or stainless steel. Suitable for water applications, such as industrial cleaning equipment.  
OPEN FS-380 DATASHEET
Shuttle Type Low Cost Flow Switches
Shuttle-type flow switches are designed for moderate to high flow rates. 
Shuttle Flow Switch For Threaded Plastic Piping

For Threaded Plastic Piping

Low cost, polypropylene shuttle type switch. FDA/NSF approved. Flow rate settings: 0.25 GPM to 5.0 GPM


OPEN FS500 DATASHEET
Shuttle General Purpose Straight-Through Flow Path

General Purpose Straight-Through Flow Path 

Durable and accurate flow switches in bronze or stainless steel. Available as fixed or adjustable. Ideal for improper flow rates in high volume lubrication, cooling or process systems
OPEN FS-200 DATASHEET
OPEN FS-400 DATASHEET
Shuttle Flow Switch For Plastic Piping

For Plastic Piping

Low cost corrosion-resistant PVC fixed flow switch with a flow rate of 0.5 GPM or 2.0 GPM



OPEN FS-440P DATASHEET
Shuttle Paddle Wheel Flow Sensors RotorFlow

Paddle Wheel Flow Sensors RotorFlow® 

Highly visible design offers accurate visual indication, flow rate sensing and switching. Available with brass, stainless steel or hydrolytically-stable polypropylene housings. 
OPEN ROTORFLOW DATASHEET
Other Piston Type Flow Switches
Piston-type flow switches are designed for low flow rates. Available in a variety of types to suit specific pressure applications or design parameters
Molded Plastic Flow Switch for Industrial Applications

Molded Plastic for Industrial Applications

Economical Ryton® fixed flow switch for flow rate between 0.1 GPM to 1.5 GPM



OPEN FS-4 DATASHEET
Straight-Through Flow Path Flow Switch for Industrial Applications

Straight-Through Flow Path for Industrial Applications

Economical flow switch with pre-adjusted set points, used in photocopiers, heavy-duty floor cleaners and industrial dishwashers


OPEN FS-6 DATASHEET

Straight Flow Path Flow Switch with Low Pressure Drop

Straight Flow Path with Low Pressure Drop

Slim polypropylene fixed flow switch for flow rate between 0.5 GPM to 5 GPM. Used to reduce pressure drop to a minimum. 


OPEN FS-150 DATASHEET

Miniature Brass Piston Flow Switch

Miniature Brass

Compact fixed flow switch for tight instrumentation packages for flow rate between 0.10 GPM to 1.50 GPM. 
Designed for use with water and oil, these switches are suitable for high volume OEM applications.
OPEN FS-927 DATASHEET

Precision-Calibrated General Purpose Piston Flow Switch

Precision-Calibrated General Purpose

Constructed from brass or stainless steel, fixed flow switch suitable for liquids and gases, factory preset for actuation at specified flow rates.
OPEN FS-925 DATASHEET
Precision-Calibrated Low Flow Piston Flow Switch

Precision-Calibrated Low Flow

Constructed from brass or stainless steel, fixed flow switch suitable for liquids and gases, factory preset for actuation at specified flow rates.
OPEN FS-926 DATASHEET
General Purpose Straight-Through Path Piston Flow Switch

General Purpose Straight-Through Path

Fixed or adjustable explosion-proof flow switch with a durable construction ideal for detecting improper flow rates in high volume lubrication, cooling or process systems
OPEN FS-200 DATASHEET
Oil Flow Monitoring with Viscosity Compensation Piston Flow Switch

Oil Flow Monitoring with Viscosity Compensation

Fixed pre-set explosion-proof oil flow switch. Compensates for viscosity changes in fluid automatically.

OPEN FS-930 DATASHEET
Tools & resources
Advantages of Gems flow sensors and switches
An Wide Range of Task Dedicated Items
Gems Sensors features a very wide range of sensors and switches, each dedicated to a specific role.
Long-Life Products
Gems Sensors' products are constructed from highly corrosion resistant materials intended to endure heavy wear and tear.
Tailor Made Items
Gems' flow switches are built to have fixed or adjustable actuation settings, giving them the ability to be fitted to practically every use.
Accurate Information Feedback
Gems' turbine flow sensors are renowned for their high accuracy for liquid monitoring, along with fast-reaction emergency shutdown systems.

Specifying the Right Switch

We colloborate with in-house engineering teams to identify the most effective solution for your application, helping you to select the best fit from hundreds of models available
Hawco Gems Flow Sensors & Switches
Hawco Gems Flow Sensors & Switches

Reliable supply chain

We offer inventory support to help maintain stock levels and reduce time-to-market for new products. 
Here to support you

Discuss your application

We would like to understand your project scope to help specify the right flow sensor for your product. Call +44 (0)1483 869 070 or email sales@hawco.co.uk

Got a technical question?

We can provide detailed information about any Gems product and recommend whether it is right for your requirements. 

Special requirements

With a wide choice of construction materials, mounting types and electrical termination, we can suggest customised solutions. Contact us on +44 (0)1483 869070 or email sales@hawco.co.uk.