This item is now discontinued. We recommend the following as suggested replacements: EW-53010-30

YSI 550A-25 Dissolved Oxygen Meter, 25-ft (7.6-m) Probe Cables

Representative image only.
YSI Mfr # 550A-25 – Item # EW-53010-32
Polyethylene membrane reduces stirring requirements and improves response time
  • Innovative field-replaceable dissolved oxygen (DO) electrode modules save time and money
  • Waterproof, impactresistant case — IP67 rated


Specifications & Description

  • Meter TypePortable
  • Display typeLCD
  • Min Salinity0 to 70 ppt
  • Min Dissolved Oxygen0 to 50 ppm
  • Dissolved Oxygen Resolution0.01 ppm
  • Dissolved Oxygen Accuracy±0.03 ppm
  • Temperature Accuracy±0.3°C
  • Temperature compensationAutomatic
  • WaterproofYes
  • Battery4 x C batteries (included)
  • Width (cm)11.1125
  • Height (cm)22.86
  • Width (in)4
  • DescriptionDissolved Oxygen Meter, 25-ft (7.6-m) Probe Cables

Key Features

  • Innovative field-replaceable dissolved oxygen (DO) electrode modules save time and money
  • Waterproof, impactresistant case — IP67 rated

More About this Item

These DO meters feature a built-in calibration chamber that provides a 100% water-saturated environment — perfect for calibrating, transporting, and storing probe. Provide simultaneous readings of oxygen and temperature. Measurements are fast and easy with one-handed operation, large backlit display, automatic push-button calibration, and a weighted, quick-sinking probe. Low-battery indicator alerts you to change batteries. Salinity, temperature and altitude compensations eliminate the need for correlation chart.




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2 Questions | 2 Answers
Displaying questions 1-2
  • Q:

    Does this come with a carry case?
    Many Thanks
    Asked on 5/3/2011 by Gem from Leics

    1 answer

    • Staff Reviewer


      Yes, this comes with the waterproof, impact resistant case.

      Answered on 5/3/2011 by Jen from Technical Support
  • Q:

    I have a large natural fish pond and I need to know what the oxygen content of the water is. I believe it to be marginal and the test kit I am using is cumbersome and not very actuate. You need to match the colors and that's subjective.
    Would this meter do the job for me?
    Asked on 8/12/2010 by David from Upstate NY

    1 answer



      Yes, this meter will accurately measure the oxygen content of your pond.

      Answered on 8/16/2010 by Jack from Technical Support
Displaying questions 1-2

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