Humonic Optiflow 520 Digital Volumetric (Bubble) Flowmeter



flow range 0.5 ‑ 500 mL/min

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General description

A digital bubble flowmeter is one of the most useful tools in a GC lab. They are very reliable, and easy to use. The principle is that optical sensors detect when the bubble enters and exits the calibrated tube. A microprocessor then calculates the resulting volumetric flow rate and displays it on a small screen.
  • Mode: volumetric (bubble)
  • Split ratio mode: yes
  • Gases: all
  • Inlet: 1/8” I.D. flexible tubing (included)
  • Flow range: 0.5 to 500 mL/min
  • Resolution: 0.01 mL/min (for flows 0.50-9.99 mL/min), 0.1 mL/min (for flows 10.0-99.9 mL/min), and 1.0 mL/min (for flows 100-500 mL/min)
  • Accuracy: ± 3% of reading
  • Display: digital
  • Calibration: 3-point, NIST traceability, recalibration service available
  • Size: 9” H x 6” W x 5” D
  • Weight: 2.4 lbs.
  • Power: 9 V alkaline battery (automatic shutoff feature conserves battery)
  • CE mark: no
  • Data output: none

Other Notes

Included with this product are: flowmeter, glassware (flow tube), squeeze bulb, bulb clamp, and flexible tubing.


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis
Certificate of Origin
  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  3. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  4. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  5. Is Product 28679-U, Optiflow 520 Flowmeter, NIST certified?

    Product 28679-U, Optiflow 520 Flow Meter, is not NIST certified.

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