FYRA Configuration Guide: Driver Cards, Functions, and System Compatibility

The DigiVac FYRA Controller is designed with a modular structure that supports up to six installed cards, allowing users to tailor the system to their applications. These slots can be populated with a combination of  sensor cards, valve driver cards, and relay functionality, depending on the level of measurement and control required. 

For example, a typical configuration might include three sensor cards for pressure monitoring, two valve cards for control, and one relay (integrated on a valve or dedicated card) to interface with external equipment. This flexibility enables FYRA to function as both a measurement and control platform within a single unit. It is important to note, however, that while multiple cards can be installed, the system is limited in how many sensors can be actively utilized at once. FYRA supports up to three sensors operating simultaneously, so configurations must be selected accordingly to match the application needs.

FYRA Sensor Interface Cards

The DigiVac FYRA controller uses a modular driver card structure, meaning each sensor type requires a specific card installed inside the controller. This allows FYRA to support a wide range of vacuum gauges while keeping the system flexible and easy to configure for different applications.

STR-531 (Thermocouple Gauge Card)

This card is designed to operate Agilent 531 / 536 thermocouple gauge tubes (and equivalents).

Best for:

• Monitoring rough vacuum ranges
• Simple, cost-effective pressure measurement
• Applications where rugged, proven technology is preferred

A straightforward solution for basic vacuum measurement using thermocouple tubes, commonly used near pumps or in general purpose systems.

4V-STR (0.5–4.5V Analog Sensor Card)

This card interfaces with sensors that output a standard 0.5–4.5V analog signal.

Best for:

• DigiVac sensors (like piezo sensors)
• Third-party analog-output sensors
• Applications needing simple voltage-based integration

Ideal for simple, analog-output sensors, especially in or OEM environments.

AG-CM-STR (Active Gauge / Capacitance Manometer Card)

This card powers and reads active gauges and capacitance manometers using a 24V supply. This includes a 10’ FCC68 sensor cable for easy plug-and-play connection.

Best for:

• High-accuracy pressure measurement
• Gas-independent readings (especially with capacitance manometers)
• Advanced gauges from manufacturers like Agilent, Inficon, MKS, etc.

This is the most versatile and widely used card, supporting many modern digital/active gauges and precision instruments.

Adapter Board for ±15V power supply and consume less than 2 Watts paired with AG-CM-STR (Active Gauge / Capacitance Manometer Card)

This card is designed to operate active gauges and capacitance manometers that require a ±15V power supply and consume less than 2 Watts. This includes a 10’ FCC68 to DB9 interface cable for straightforward connection to compatible gauges.

Best for:

• Precision capacitance manometers requiring a ±15V supply
• Higher-accuracy vacuum measurement applications
• Integrating legacy or specialty active gauges that utilize ±15V operation

Unlike the standard active gauge card, which supports the more common single-supply gauges (typically 15–30VDC), the CM-DS card is intended for the relatively small number of active gauges and capacitance manometers that require both +15V and -15V power for operation. This expands FYRA compatibility to support specialized vacuum instrumentation and legacy gauge technologies.

STR-CONVECTRON (Convectron Gauge Card)

This card is specifically designed to operate convectron (thermal conductivity) gauges.

Best for:

• Wide-range vacuum measurement (rough to medium vacuum)
• Monitoring chamber pressure during pump-down
• Applications where a single sensor covers a broad range

A great choice when you need broad pressure coverage with a single sensor, often used on vacuum chambers.

FYRA Valve Control Cards

In addition to reading sensors, the DigiVac FYRA can actively control vacuum systems by driving valves and relays. This allows the controller to maintain pressure, automate processes, and integrate with external equipment.

Each valve function requires a dedicated driver card, selected based on the type of valve and control strategy required.

BLD-VAL-STR (Bleed Valve + Relay Card)

This card drives a bleed-type valve and includes one S.P.D.T. relay output for additional system control.

Best for:

• Introducing gas into a system to raise or stabilize pressure
• Maintaining a setpoint by bleeding air or inert gas

A great choice for basic vacuum regulation using bleed control, with the added flexibility of a relay for auxiliary control.

THR-VAL-STR-P (Throttle / Isolation Valve Card)

This card can drive up to two 24V valves directly, enabling throttle control or isolation control.

Best for:

• Controlling vacuum by restricting pump flow (throttling)
• Opening/closing valves for isolation between system sections
• Applications requiring active pressure control between upper and lower setpoints

FYRA uses upper and lower setpoints to automatically open and close valves, maintaining pressure within a defined range (hysteresis control). Ideal for closed-loop vacuum control, where the system automatically adjusts valve position to maintain a target pressure.

PROP-VAL-STR (Proportional Valve Card) 

Drives two 12V proportional valves, allowing for continuous, variable control rather than simple open/close operation.

Best for:

• Fine-tuning vacuum levels with smooth, continuous adjustments
• Processes that require tight pressure stability
• Applications where step-based control (on/off valves) is not precise enough

Instead of cycling between open and closed positions, proportional valves adjust incrementally, enabling more stable control, especially when paired with FYRA’s PID functionality. Ideal for high-precision vacuum control, minimizing fluctuations and improving process consistency.

FYRA Communication, Relay & Input Cards

Beyond sensors and valves, the DigiVac FYRA can be expanded with additional cards that enhance connectivity, system integration, and control capabilities. These cards allow FYRA to interface with networks, external equipment, and auxiliary inputs to create a more complete vacuum control solution.

WiFi-STR (Wireless Communication Card)

Enables the FYRA to be accessed wirelessly, providing remote visibility and basic control.

Best for:

• Wireless connection to the controller
• Remote monitoring of vacuum data
• Includes a limited license to vacuumnetwork.org for cloud-based viewing and data logging
• Remote process monitoring
• Data logging and trend analysis
• Applications where the system is not easily accessible

Adds remote access and visibility, allowing users to monitor and interact with their system without being physically present.

FYRA 4–20mA Card (Analog Input Card)

Enables FYRA to accept a 4–20 mA input signal, commonly used for temperature. This includes an FCC68 wire adapter for easy connection

Best for:

• Adding temperature monitoring to a vacuum process in conjunction with the Torch Data Logger
• Integrating other industrial sensors (pressure, flow, etc.) that use 4–20 mA signals
• Applications requiring multi-parameter monitoring

Expands FYRA beyond vacuum by allowing it to monitor additional process variables, making it a more complete system controller.

REL-STR (Dual Relay Card)

Provides two S.P.D.T. relays for controlling external devices.

Best for:

• Turning pumps, alarms, heaters, or other equipment on/off based on pressure conditions
• Integrating FYRA into a larger control system
• Simple automation without a PLC

Relays can be triggered based on vacuum setpoints, allowing FYRA to act as a decision-making controller within the system. Ideal for basic automation and system integration, expanding FYRA beyond measurement into full process control.

STR-MFC (Mass Flow Controller Card)

Interfaces with mass flow meters and mass flow controllers (MFCs) to both read flow rate and actively control it.

Best for:

• Controlling gas flow into a vacuum system (e.g., sccm control)
• Processes requiring repeatable and accurate gas delivery
• Applications such as coating, freeze drying, or controlled atmosphere processes

FYRA can monitor flow rate data and adjust output to maintain a desired flow setpoint, integrating flow control directly into the overall vacuum control strategy. Enables closed-loop gas flow control, making FYRA a complete solution for both pressure and flow management.

RS232 

This card adds RS232 serial communication capability to the FYRA controller, enabling data exchange with external devices such as PLCs. It provides a reliable and widely supported method for remote monitoring, data logging, and system integration.

Best for:

• Logging vacuum measurements to a computer
• Integrating FYRA with PLCs and industrial control systems
• Remote monitoring and data collection applications

The RS232 card allows users to transmit vacuum data directly to external software for analysis and recordkeeping. It is particularly useful in laboratory, industrial, and process control environments where continuous data collection and communication with other equipment is required. 

FYRA Web Bundles 

FYRA End of Primary Drying Detection 

The FYRA for End of Primary Drying Detection is a bundle that assists in detecting when most of the water or residual solvent from a product has been removed or the end of primary drying has been reached in a vacuum drying application. This bundle is ideal for Life Science applications such as API, university labs, research, and drug manufacturing.  

FYRA for End of Primary Drying Detection Bundle Includes:

• FYRA controller
• TriSENS Capacitive Piezo (DPCP) Vacuum Sensor: Measurement Range: 10^(-5)Torr to 1000 Torr
  • (1) AG-CM driver card
• Lesker 275 Convection Sensor: Measurement Range: 0.1 mT to 1000 Torr
  • (1) STR-CONVECTRON driver card
• Convection Enhanced Gauge Cable (10′ long)
• Optional: KF16 Bleed Valve
  • (1) BLD-VAL-STR driver card
• Optional: KF25 Manual Purge Valve
  • No driver card needed
• Optional: NIST traceable documentation

FYRA Distillation Vacuum Controller Bundle

The DigiVac FYRA Vacuum Controller Distillation Bundle specifically was created to include diagnostic capabilities.  It includes two sensors – one connected to the system and one connected to the roughing pump.  By comparing the readings between the two sensors, you can verify that the system is operating properly and identify any potential leaks or performance issues that may arise.

FYRA Distillation Vacuum Controller Bundle Includes:

• FYRA Vacuum Controller
• (2) Agilent 536 KF25 Thermocouple Sensors and driver cards
  • (2) STR-531 driver cards
• (1) Bellows-type Throttle Valve and driver card
  • (1) THR-VAL-STR-24VB driver card
• Options: WiFi
  • (1) WiFi-STR driver card
• Optional: Installation Kit (Aluminum Wing Clamps + Stainless Steel/Viton Centering Rings).

FYRA Bleed Vacuum Controller

The FYRA Bleed Vacuum Controller is a mass flow controller alternative solution for venting or bleeding in gasses (like nitrogen or argon) to a chamber. This process controller works in two ways: maintaining a particular vacuum or bleeding in a specific flow rate. It has an accuracy range of 1 mT to 6 Torr (which can be easily modified to include different sensors) and a Bleed Control Range of 10 mT to 6 Torr.

The FYRA Bleed is for distillation applications that would benefit from the increase of molecular flow (such as short path, freeze-drying, vacuum drying, and others) that you would get from the bleeding of gases into your system.  It has a flow range from 35 SCCM to 3620 SCCM.

FYRA Bleed Vacuum Controller Bundle Includes:

• FYRA Controller
• 536 KF25 sensor and sensor card
  • STR-531 driver card
• VacStable bleed valve and valve card
  • BLD-VAL-STR driver card
• WiFi included
  • (1) WiFi-STR driver card

FYRA Dual Convectron Controller 

The FYRA Dual Convectron Controller performs like the regular FYRA, but it includes 2 driver cards that allows it to be paired up with convection-enhanced pirani sensors (such as the Lesker KJL275071, and KJL275196) in addition to regular vacuum sensors. Can measure from 1.0 x 10-4 to 1000 Torr. 

The FYRA Dual Convectron Controller can be used in many industrial applications such as semiconductor manufacturing, load locks, leak detection, vacuum coating, and freeze dryers. 

FYRA Dual Convectron Controller Bundle Includes:

• FYRA Convectron Controller with 10 volt DC Output and USB for data download and documentation
• (2) Convection-enhanced pirani sensors
  • (2) STR-CONVECTRON driver cards
• Sensor Options:
  • (2) Lesker 275 1/8″ NPT (KJL275071) + 2 sensor cables
  • (2) Lesker 275 KF25 (KJL275196) + 2 sensor cables

Why Fyra?

The modular design of the FYRA Vacuum Controller makes it easy to configure a system that fits your specific vacuum process. Whether you need simple pressure measurement, advanced closed-loop vacuum control, gas flow management, or seamless integration with existing equipment, FYRA’s interchangeable driver cards provide the flexibility to build the right solution without purchasing unnecessary hardware. As your application evolves, the controller can be expanded with additional sensor, valve, communication, and relay cards, making it a scalable investment for laboratory, research, and industrial environments.

If you’re ready to build a vacuum control system tailored to your application, DigiVac can help. Our team can recommend the ideal combination of driver cards, sensors, and accessories based on your process requirements, ensuring you get the performance and functionality you need from day one.

Ready to get started? Contact DigiVac today to discuss your application, request a custom configuration, or purchase a FYRA Vacuum Controller. Whether you’re upgrading an existing system or designing a new one, we’re here to help you select the right solution with confidence.