Low Flow Gas Meters (RFQ)

Precision Low-Flow Measurement Solutions

Rheotherm thermal flow meters provide repeatable, maintenance-free measurement for the most challenging low-flow gas applications.

• Extreme Low-Flow Range: Measures from 50 SCCM up to several 280 SCFM.
• Maintenance-Free Design: Unobstructed flow path with no moving parts to wear, stick, or break.
• Media Versatility: Accurately measures low or high-viscosity liquids, slurries, liquefied gases, and corrosive chemicals (e.g., Methane, Hydrogen, CO₂).
• Built for Extremes: Options for Hazardous Locations (Intrinsically Safe/Explosion-Proof) and compatibility with most fluids via various tube materials.
• High Turndown: Typical 10:1 range, with custom options up to 200:1.
• Smart Diagnostics: Includes self-diagnostics and optional LCD display for flow rate, temperature, and totals.
• Proven Quality: Manufactured by Bionetics since 1978 under an ISO-9001:2015 certified program.

How to Request a Quote:

1. Submit Online: Complete the form  on this page with your process details or upload your datasheets for review.
2. Email Us: Download and complete the Flow Application Data Sheet and email it to us at sales-flow@bionetics.com.

You can also call or visit our Contact Us page for telephone, fax, and email information.

• SPECIFICATIONS
• FLOW RANGES
• DOCUMENTATION

	Standard	Options
Temperature	Process: 0 – 140°F (-18 – 60°C) Environment: 0 – 120°F (-18 – 50°C)	-20 – 350°F (-30 – 175°C)
Pressure	0 – 1,000 PSI	Up to 30,000 PSI
Calibration Ranges	10:1 Turndown; Flow rate: 0.001 to 320 SCFM (.03 to 9060 SLPM)	– Up to 200:1 turndown – Four calibration channels available (for multiple flow ranges or different fluids using the same sensor)
Calibration Accuracy	± 1% of reading typical
Response Time	1 sec. ; 3 – 5 sec. typ. (63% of range);	Time constant/delay option
Repeatability	± 0.5% of reading
	Standard	Options
Line Sizes (flow range dependent)	Capillary; 1/16”; 1/8”; 3/16”; 1/4” 3/8”; 1/2”; 5/8”; 3/4”; 1”	Other sizes via fittings/adapters
Process Connection	Plain tube stubs suitable for compression fittings	– MNPT; – Tri-Clover (Sanitary); – SS Flange (1/2” – 2”): Most other fittings available
Wetted Material	316 SS	– Hastelloy C-276®; – Monel®; – Alloy 20; – Titanium; – Tantalum; – Inconel
Display		2 X16 backlit LCD with selectable display of: – Mass/volume flow rate – Temperature – Total accumulated flow
	Standard	Options
Enclosure	Sensor:  PVC Integrated Electronics: NEMA 4X Cast Aluminum Remote Electronics: NEMA 4	Sensor: Stainless steel Remote electronics: – Stainless steel – NEMA 7 Explosion-proof
Hazardous Environment		Integrated electronics: FM-Approved for: – Class I, Div. 1, Groups B,C,D – Class I, Zone 1, IIB+H2 (US) – Class II, Div. 1, Groups E, F, G – Class III, Div. 1 Remote electronics: Same as above except addition of Group A using ISB
Outputs	4 – 20 mA (flow rate) or Serial Burst with Flow Rate, Totalizer, and Fluid Temperature	– 0 – 10 or 0 – 5 VDC; – Pulse (5 VDC open collector); – HART (4-20 mA); – SPDT relay; – 4 to 20 mA temp
Input Power	24 VDC ±4V (200 mA; 300 mA w/display option)	110/230 VAC ±10V

Inline Sensor Flow Capacities for Gases

	TUBE SIZE
FLOW RATE LIMITS	C	1/16	1/8	3/16	1/4	3/8	1/2	5/8	3/4	1
Extended Maximum	0.027	1.25	5	11	20	45	80	125	180	320
Normal Maximum	0.017	0.75	3	7	15	34	70	109	160	280
Normal Minimum	0.0017	0.02	0.1	0.2	0.4	0.9	1.6	2.5	3.6	6.4
Extended Minimum	0.0009	0.0017	0.05	0.1	0.2	0.5	0.8	1.2	2	3.2
	SCFM

Product Brochure	Rheotherm Flow Application Data Sheet (download document)
Rheotherm Method of Operation	Rheotherm Sensor Selection Guide
Standard Dimensions Inline Sensor	Rheotherm Model Number Guide
	Rheotherm Model 210 Product Manual