Transmitter

Transmitter & Controllers

From single-parameter control to multi-parameter automation, the 9900 and 9950 deliver scalable performance. The 9900 provides modular single-channel measurement, while the 9950 integrates up to six sensors with advanced logic and control.

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Turning Sensor Data into Process Intelligence

GF transmitters transform sensor signals into powerful process intelligence. Engineered for precision, reliability, and seamless integration, they deliver real-time data that drives confident control and smarter automation.

Trusted across water treatment, chemical processing, industrial utilities, and dosing applications, they measure flow, pH/ORP, conductivity/resistivity, salinity, temperature, pressure, level, dissolved oxygen, and 4–20 mA inputs. Optimizing your performance and elevating your process excellence starts here.

Transmitter - Scymaris
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Precision Measurement Solutions for Pinpoint Accuracy

From single-parameter control to advanced multiparameter automation, the 9900 and 9950 Transmitters deliver scalable performance for demanding process applications. The 9900 offers flexible, modular single-channel measurement, while the 9950 consolidates up to six sensors into one powerful platform with advanced logic and control functions—helping you optimize panel space, simplify integration, and enhance operational efficiency.

9950 Transmitter

Multi-Channel, Multi-Parameter Controller

9950

The Signet 9950 combines the easy setup of a transmitter with the versatility of a controller. Compact yet powerful, the 9950 offers up to six user-configurable channels. With six channels, you can save real estate on your panel by purchasing a single controller in a ¼ DIN package. Digital sensors connected to the 9950 can be wired in a daisy chain configuration to save on wiring costs as well. Having standard features including Derived measurements (delta, sum, and ratio), Boolean logic  - A | B | C,  A & B & C,  A | (B & C),  A & (B | C), up to 4 binary inputs, up to six analog outputs, up to eight relays with available functions including Low, High, Date/ Timer, WindowIn, WindowOut, Adjustable Hysteresis, On Delay, Proportional pulse, and Volumetric pulse. 

9900

Single-Channel, Multi or Single-Parameter Transmitter

9900

The Signet 9900 is a versatile, single-channel multiparameter display, designed to deliver reliable performance across a wide range of applications. Providing clear “at-a-glance” visibility, intuitive operation, and simple setup. With flexible compatibility, supporting Flow, pH/ORP, Conductivity/Resistivity, Salinity, Temperature, Pressure, Level, Dissolved Oxygen, and 4–20 mA sensors. Easily field upgrade functionality by choosing from a suite of optional output modules, including dual SPDT Relays, additional 4-20mA output, batch control function, or Modbus RTU.

Flexible module integration

Expanded capabilities

Expand the performance of your 9900 and 9950 transmitters with a comprehensive range of plug-in modules. From Direct Conductivity/Resistivity and 4–20 mA outputs to Relay, Batch, H COMM, and Modbus RTU communication, these modules enhance flexibility, connectivity, and control—allowing you to tailor each transmitter to your exact process requirements.

9950 Series

Discover all available modules for the 9950 Transmitter

9900 Series

Discover all available modules for the 9900 Transmitter

Single-Channel Direct Conductivity/Resistivity Module
  • Allows direct connection to single conductivity/resistivity sensor up to 30m (100 ft) in cable
  • For applications separated by more than 30m (100 ft) use 3-2850-51-XX Sensor Electronics
Single-Channel Conductivity/Resistivity

Dual-Channel Direct Conductivity/Resistivity Module
  • Allows direct connection to two conductivity/resistivity sensors up to 30m (100 ft) in cable
  • For applications separated by more than 30m (100 ft) use 3-2850-51-XX Sensor Electronics
Dual-Channel Conductivity/Resistivity

Dual-Channel 4-20mA Current Loop Output Module
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Dual-Channel Conductivity/Resistivity

Modbus RTU Module

Connects the 9950 to existing Modbus RTU, serial RS485, and automation networks

  • Allows digital access to live measurement readings
  • Simplifies the interfacing of the 9950 to automation networks
Modbus RTU Module

Relay Module

Three options:

  • 4 dry-contact relays
  • 2 dry-contact and 2 solid state relays
  • 2 dry-contact and 4 binary inputs
Relay Module

H COMM Module
  • Allows communication between the 9900 Transmitter and a HART®-enabled device
  • Allows access to primary and secondary measurements remotely
  • Allows user to remotely adjust the 4 and 20 mA settings
  • Not compatible with Batch module
H COMM Module

4-20 mA Module
  • Adds a second 4-20 mA output
  • Output can be used for primary or secondary measurement
4-20 mA Module

Direct Conductivity/Resistivity Module
  • Allows direct connection to the conductivity/resistivity sensor up to 30m (100 ft) in cable
  • For applications separated by more than 30m (100 ft) use 3-2850-51-XX Sensor Electronics
Conductivity/Resistivity

Batch Module

Adds batch control capability to the 9900 Transmitter

  • Compatible with all GF S3L and frequency output flow sensors
  • Up to 10 batch sizes can be stored in one 9900 with customized names and K-factors available for each batch
Batch Module

Modbus RTU Module

Ability to transfer live readings, units of measure, and measurement status

  • Connects to PLCs and SCADA systems
  • Supports the serial Modbus RS-485 standard
Modubus Module

Relay Module

Adds two programmable dry-contact relays

  • Hysteresis and time delay available for each relay
  • Depending on the sensor type, there are a total of 23 relay modes available
Relay Module

Field Transmitter

Signet field transmitters transform sensor signals into powerful process intelligence. Engineered for precision, reliability, and seamless integration, they deliver real-time data that drives confident control and smarter automation.

Trusted across water treatment, chemical processing, industrial utilities, and dosing applications, they measure flow, pH/ORP, conductivity/resistivity, salinity, temperature, pressure, level, dissolved oxygen, with blind 4–20 mA inputs, or optional 9900-1 display transmitter either integral or universal mounted—empowering you to optimize performance and elevate process excellence.

Our comprehensive range of measurement products includes liquid analysis instruments (conductivity, pH/ORP, chlorine, dissolved oxygen (DO)), flow meters (ultrasonic, magmeters, paddlewheel), transmitters (single and multi-channel), as well as level, temperature, and pressure sensors.

Transmitter - Scymaris

Key Industries

Across critical industries, accurate measurement is the foundation of safe and efficient process control. GF transmitters convert sensor signals into reliable, real-time data that enables precise monitoring and automation. Designed for demanding environments, they support a wide range of parameters and applications and empower operators to maintain compliance, optimize performance, and ensure long-term system reliability.

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Water Industry

In the water industry, precise measurement and control are essential to ensure safety, efficiency, and regulatory compliance. GF transmitters provide reliable monitoring of flow, pH/ORP, conductivity, level, and other critical parameters across drinking water, desalination, and wastewater treatment. With robust design and seamless sensor integration, they enable stable operations and long-term performance in demanding environments.

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Chemical Process Industry

In chemical processing, accuracy and responsiveness are vital to protect processes and assets. GF transmitters deliver real-time insight into key parameters such as flow, pressure, pH/ORP, conductivity, and temperature. Built to perform in aggressive and corrosive conditions, they support consistent dosing, safe chemical handling, and optimized process control.

Success Stories

Scymaris - Liquid Analysis

Ecotoxicology specialist Scymaris relies on various analytical sensors, such as conductivity or dissolved oxygen (DO), and the 9950 Six-Channel Transmitter by GF Industry and Infrastructure Flow Solutions, for failsafe environmental fate studies.

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Aquarium of the Pacific, USA

Over 250 GF measuring systems operate 24/7 to help ensure optimal conditions for a diverse array of exhibits. The aquarium features over 20 large exhibits and 60 smaller ones, each with unique water quality requirements. With a total volume exceeding 1.2 million gallons, sustaining these conditions is critical for the health and well-being of the animals.

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Neustark - Carbon Capture Removal

Due to the harsh environment in the reactor, Neustark chose to implement solutions for Process Automation from GF Industry and Infrastructure Flow Solutions, consisting of conductivity and flow sensors, pH electrodes, as well as the 9950 Six-Channel Transmitter.

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Shedd Aquarium - Life Support System

At the heart of Shedd Aquarium’s mission is conservation, starting with precision. Through a long-term partnership, GF Industry and Infrastructure Flow Solutions provides reliable Signet instrumentation and automation to manage 5 million gallons of water. From nonmetal valves to precise flow meters, GF supports Shedd with technology that benefits both animal and environmental care.

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Want More Stories?

Have a look at our reference case collection and learn how GF Industry and Infrastructure Flow Solutions has helped our customers improve water quality and ensure operational safety.

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As a global company, we’re committed to supporting you, no matter where you or your customers are. Our regional centers provide repair and support services, while our team of experts specializes in tailoring customized solutions for your unique application.

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Georg Fischer LLC - Irvine, CA / Industrial Group Americas

9271 Jeronimo Road

92618 Irvine

United States

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