MT3809 Metal Tube Variable Area Flow Meter
Proven Performance for Demanding Process Conditions
The MT3809 Series metal tube variable area flow meter delivers reliable gas and liquid flow measurement across an exceptionally wide range of pressures, temperatures and flow rates. Proven in thousands of installations worldwide, it is a practical, economical choice for demanding industrial applications.
Available with mechanical or electronic indication, alarms and digital communications, the MT3809 metal tube rotameter can be configured to meet a wide range of process and hazardous-area requirements.
Now backed by an industry-leading 24-month warranty for added confidence in every installation.
Features & Benefits
- Wide Operating Range: Measures gas and liquid flow from very low to high flow rates across process temperatures from -198°C to 420°C (-325°F to 788°F) and standard pressures up to 6,250 psi / 430 bar. Turndown ratio is 10:1, with 1%, 2%, 3%, and 5% accuracy options available.
- Flexible Configuration Options: Choose from multiple materials, process connections, indicator configurations, alarms and control options, with more capabilities through our custom engineered specials program.
- Digital Display & Local Operator Interface: Optional transmitter provides flow indication, totalization and alarms, with parameter adjustments available locally without removing the enclosure cover.
- Material Traceability: NACE and 3.1-level material traceability options are available to meet demanding EPC projects, industrial and sour-service documentation requirements.
- Global Certifications & Approvals: Extensive hazardous-area, functional safety, marine and regional approvals help simplify specification for installations worldwide - ATEX, IECEx, SIL 2, CSA, UL, and more. Explosion Proof (XP) and Intrinsically Safe (IS) options also available.
- Process & Safety System Integration: Available 4–20 mA HART and FOUNDATION Fieldbus communications, plus alarm configurations for integration with plant control and safety systems. The MT3809G 4–20 mA analog output is SIL 2 approved for applicable safety instrumented functions.
- 24-Month Warranty: Industry-leading warranty coverage provides added confidence in the long-term reliability of your MT3809 investment
Applications
- Oil & gas production and processing
- Wellhead platforms
- Chemical and petrochemical processing
- Refining
- Power generation
- Industrial gas systems
- Flare stack flow measurement
- High-pressure and high-temperature flow measurement
- Hazardous-area installations
| Type of Media | Gas / Liquid |
|---|---|
| Flow Measuring Principle | Variable Area (VA) |
| Flow Range | Water: 440 gpm / 100,000 l/h, Air: 750 scfm / 1200 m3n/hr |
| Accuracy Range | ±2% FS / Class 2.5 VDI / VDE, ±1% FS / Class 1.6 VDI / VDE, ±5% FS / Class 4 VDI / VDE, ±3% FS / Class 2.5 VDI / VDE |
| Repeatability | All options except ELF: 0.25% FS, ELF: 1% FS |
| Operating Temperature | -198°C - 420°C |
| Measure/Control | Measure Only (Meter) |
| Max Flow | 20000 slpm |
| Max Flow | 21237000 sccm |
| Max Flow | 100000 l/hr |
| Max Operating Pressure | 430 bar |
| Max Temperature | 420 celsius |
| Ingress Protection | IP66, IP67, Nema 4x, IP65 |
| Hazardous Area Approved | Class 1 Div 2, Class 1 Div 1, Zone 2, Zone 1, IECEx, CSA, UL, NEPSI, KOSHA |
| Accuracy (FS) | ±2% FS, ±1% FS, ±5% FS, ±3% FS |
| Connectivity | Analog (4–20 mA), Analog (0–20 mA), Analog (0–10 V), Analog (0–5 V) |
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Use the following guide (model code information from data sheet) to translate the CAD configurations available below. If you need assistance or can’t find what you’re looking for, please contact Applications Engineering or your local Brooks Instrument representative.
Example: 3809G - A - 07 - A - 1 - A - 0
| Meter Series | Construction | Meter & Connection Sizes | Connection Type | Indicator Configuration | Electronics | Valve/Flow Controller |
| 3809G | A - Flange RF Std | See data sheet | A - NPT-Female w/Viton O-Rings | 1 - Aluminum Housing | A - Indicator only | 0 - None |
| B - Flange RF Oversized | B - NPT-Female w/Teflon O-Rings Low Flow Valve on Inlet - Typical for Sizes 0, 1, 2 | 2 - 316SS Housing | B - Inductive Alarm, 1 Switch | A - Valve on Inlet - Viton Seals | ||
| C - Flange RF 2x Oversized | See data sheet | See data sheet | See data sheet | |||
| D - Threaded Female Std | ||||||
| E - Threaded Female 2500 lbs | ||||||
| F - Threaded Male | ||||||
| See data sheet |
Frequently Asked Questions
The Brooks Instrument MT3809 uses the variable area measurement principle to measure gas and liquid flow. As fluid passes through the metering tube, it raises a float to a position proportional to the flow rate. A magnetic coupling transfers the float position to an external indicator, allowing flow to be measured without direct visual access to the process fluid. Optional transmitters enable remote flow monitoring and integration with plant control systems.
Yes. The MT3809 Series is designed to measure both gas and liquid flow across a wide range of industrial process conditions. Available materials, flow ranges and connection options make it suitable for applications including oil and gas production, chemical processing, refining, power generation and industrial gas systems. The meter is configured for the specific process fluid and operating conditions.
Yes. The MT3809 is available with an optional 4–20 mA transmitter with HART communication, enabling remote flow monitoring and integration with process control systems. FOUNDATION Fieldbus communication is also available. Depending on the configuration, additional features include a local LCD display, flow totalization, high and low flow alarms, and pulse output.
The MT3809 and MT3810 are both metal tube variable area flow meters designed for industrial gas and liquid measurement. The MT3809 offers a broader range of configuration options, including electronic transmitters and alarms, along with higher maximum temperature capabilities. The MT3810 is an alternative for applications requiring basic mechanical flow indication. Selection depends on the required flow range, operating conditions and instrumentation needs.
Yes. The MT3809 Series is available with hazardous-area approvals, including ATEX, IECEx, CSA and other regional certifications. Intrinsically Safe (IS) and Explosion Proof (XP) configurations are available to meet different installation requirements. A 316 stainless steel flameproof indicator housing is also offered for demanding hazardous-area environments. The appropriate configuration depends on the area classification and applicable certification requirements.
Yes. The MT3809 offers SIL 2 capabilities for applicable safety instrumented functions. These include approved inductive alarm configurations and the 4–20 mA analog output of the transmitter. These options enable the meter to provide flow information to safety instrumented systems. Engineers must verify the selected configuration and the requirements of the complete safety function when specifying the instrument.
The MT3809 is available with a stainless steel tag featuring a permanently laser-etched QR code for durable, maintenance-free instrument identification. The QR code provides access to key information, including the model code, serial number, flow range, tag number, process media, operating temperature, and operating pressure. Information can be tailored to customer requirements, subject to the QR code's capacity of approximately 200–250 alphanumeric characters, which may vary depending on the language or character set used.