Low Flow Indicating Paddlewheel Flow Meter
Micro-flow meter
Volume discounts available
Volume Discount Schedule
Quantity | Price each |
---|---|
1-4 | $373.74 |
5-9 | $355.05 |
10-24 | $347.58 |
25-49 | $332.63 |
50-99 | $325.15 |
100+ | $317.68 |
Added to Your Shopping Cart
Configuration complete.
Please add to cart to keep it or exit the configuration
Please add to cart to keep it or exit the configuration
Failed to Save Configurations, Click on Configure Button Start Again
- NEMA 4X (IP56) Enclosure
- 6-Digit LCD
- Displays both Rate and Total
- Non-Volatile Programming and Total
- For Clean Liquids
FTB321D Model Options
View all modelsEdit these specs to order a different model. Not all combinations are valid. Options compatible with previous selections will be in bold.
*Highlighted options are not compatible. Please select a different combination.
Flow Range
Max Process Temperature
Max Operating Pressure
Wetted Materials
Output Signal
Supply Power
Process Connection Type
Process Connection Size
Display
Category
Accuracy
The FTB300 Series of digital paddle wheels are an economical choice for low flow rate applications. They use Infra-red light beam technology. Available connections include 1/8 FNPT, 1/4 FNPT and 3/8" OD tube fittings. Six available flow ranges as low as 30ml/min to 7000 ml/min. No display models have a 5 Vdc current sinking pulse output. Units with displays have a 6-digit LCD, with up to 4 decimal positions that display both flow rate and total. All units include an open collector alarm output.
User selectable scale factors include: flow units, gallons, liters, ounces, and milliliters. Time units include: minutes, hours, days. Users can also program custom units. Programming values and total are stored in the non-volitile memory. The total reset function can also be disabled. Standard units have a clear PVC viewing lens, PVDF chemical resistant lens are available as an option. The enclosure is a weather resistant Valox PBT and rated NEMA 4X (IP56).
SPECIFICATIONS
Max Working Pressure:
PVC Lens: 9 bar (130 psig) at 21°C (70°F)
PVDF Lens ("-PVDF" Option): 150 psig (10 bar) @ 21°C (70°F)
Max Fluid Temperature:
PVC Lens, FNPT Connectors: 54°C (130°F) at 0 PSI
PVDF Lens ("-PVDF" Option), Tubing Connectors: 93°C (200°F) at 0 PSI
Full Scale Accuracy: ±6%
Input Power Requirement: 9 to 28 Vdc
Sensor Type: Infrared light beam
Alarm Output: Open collector 30 Vdc max
Enclosure: NEMA 4X (IP56)
Approximate Shipping Wt: 0.45 kg (1 lb) Materials of Construction
Body, Paddle, Axle Material: PVDF Connector Material
FNPT Connections: PVC
Tubing Connectors: PVDF Viewing Lens Material Option
Clear See Through: PVC
Opaque Chemical Resistant: PVDF (optional)
O-Ring Seals: FKM (EPDM optional)
Compression Seal to Pump: PVC Sensor Only
Models: 5 Vdc digital square wave (2-wire)
Output: 3-wire shielded cable, 1.8 m (6')
User selectable scale factors include: flow units, gallons, liters, ounces, and milliliters. Time units include: minutes, hours, days. Users can also program custom units. Programming values and total are stored in the non-volitile memory. The total reset function can also be disabled. Standard units have a clear PVC viewing lens, PVDF chemical resistant lens are available as an option. The enclosure is a weather resistant Valox PBT and rated NEMA 4X (IP56).
SPECIFICATIONS
Max Working Pressure:
PVC Lens: 9 bar (130 psig) at 21°C (70°F)
PVDF Lens ("-PVDF" Option): 150 psig (10 bar) @ 21°C (70°F)
Max Fluid Temperature:
PVC Lens, FNPT Connectors: 54°C (130°F) at 0 PSI
PVDF Lens ("-PVDF" Option), Tubing Connectors: 93°C (200°F) at 0 PSI
Full Scale Accuracy: ±6%
Input Power Requirement: 9 to 28 Vdc
Sensor Type: Infrared light beam
Alarm Output: Open collector 30 Vdc max
Enclosure: NEMA 4X (IP56)
Approximate Shipping Wt: 0.45 kg (1 lb) Materials of Construction
Body, Paddle, Axle Material: PVDF Connector Material
FNPT Connections: PVC
Tubing Connectors: PVDF Viewing Lens Material Option
Clear See Through: PVC
Opaque Chemical Resistant: PVDF (optional)
O-Ring Seals: FKM (EPDM optional)
Compression Seal to Pump: PVC Sensor Only
Models: 5 Vdc digital square wave (2-wire)
Output: 3-wire shielded cable, 1.8 m (6')
Model with Display | Model without Display | Range | |||||
---|---|---|---|---|---|---|---|
1/8 FNPT | 1/4 FNPT | 3/8" OD Tube | 1/8 FNPT | 1/4 FNPT | 3/8" OD Tube | lpm | gph |
FTB311D | FTB321D | FTB331D | FTB311 | FTB321 | FTB331 | 0.03 to 0.3 | 0.48 to 4.7 |
FTB312D | FTB322D | FTB332D | FTB312 | FTB322 | FTB332 | 0.1 to 1 | 1.6 to 15.8 |
FTB313D | FTB323D | FTB333D | FTB313 | FTB323 | FTB333 | 0.2 to 2 | 3.2 to 31.7 |
FTB314D | FTB324D | FTB334D | FTB314 | FTB324 | FTB334 | 0.3 to 3 | 4.8 to 48 |
FTB315D | FTB325D | FTB335D | FTB315 | FTB325 | FTB335 | 0.5 to 5 | 7.9 to 79 |
FTB316D | FTB326D | FTB336D | FTB316 | FTB326 | FTB336 | 0.7 to 7 | 11.1 to 111 |


Rated 5 out of
5
by
Engineer from
Great little flow meter
We purchased this flow meter for a test project and we really loved the ease of use and accuracy. Would definitely recommend this product to others.
Date published: 2015-11-24
Rated 5 out of
5
by
Thermal Gremlin from
Right Tool for the Job.
Bought this, received fast, fairly priced, and the perfect tool for my needs.
Date published: 2016-04-29
Rated 1 out of
5
by
Josh2 from
Fittings don't fit
The fittings that came with the flow meter did not actually fit. And they only sent one. We have been in contact with Omega for several weeks now trying to fix the issue and it has not been resolved.
Date published: 2021-03-11
Rated 4 out of
5
by
Korn from
Great product
Good and precise flow meter, in addition, should have a hard reset switch, in case of the error
Date published: 2016-10-10

If using a FTB323D flow meter with a PG-25 (25% propylene glycol) water mixture, is there a need to do any extra calibration to ensure the meter is recording accurately for the fluid type?
Thank you for your inquiry about the low flow meter. Please note that the liquid must clear, not opague and works best with clear liquids based on the infrared sensor to measure the flow.
Date published: 2022-02-15
What are the dimensions of the FTB311 Micro-Meter
Thank you for your question.
A file has been sent to your email with dimensions for this part..
Date published: 2019-07-01
Is it applicable for air flow?
Thank you for your inquiry! Unfortunately, these units will not work properly with air flow. They will only work with clean liquids
Date published: 2022-01-26
Do you have a larger unit that can measure ~ 1-10 gal/min?
Thank you for your inquiry about a flow meter. Please compose an email and send to flow@omega.com and can provide options that best fits your application.
Date published: 2020-07-25
What are the dimesions of this meter?
Please contact the Flow engineering department with this request and they will send you the details. Please send to flow@omega.com
Date published: 2019-10-18
When this meter totals the volume does it account for reverse flow by subtracting from the volume total so that a tank level can be estimated from flow in and out?
No matter which direction the paddlewheel spins the meter will accumulate a positive total.
Date published: 2019-12-19
What are the dimensions for this part, with and without the LCD screen?
Thank you for your inquiry. It would be best to compose an email and forward to flow@omega.com and will have our design team provide the information for this microflow meter.
Date published: 2020-02-19
The flowmeter stopped working after 4 months installed in a pressure manifold. The sensor had continuous power during the time, the failure was found on the infrared sensor once the flowmeter was replaced. What is the life expectancy of the sensor?
Thanks for your question. The life expectancy of the flow meter depends on the each individual application. Customers have this flow meter after 3 years and still working while others fail after 4 months. Send us an email or call us with more details of your application.
Date published: 2019-11-09