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5000 / 5100

Product Recycling Recycling

Laboratory Instruments for BOD Tests


Both instruments feature: auto-calibration, large, graphic displays and low keypad profiles for maximum efficiency.

YSI 5000/5100 Laboratory BOD and DO Meters
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Microprocessor-based, the YSI 5000 and 5100 will store 100 sets of data with RS-232 interface for direct link to your computer. Both models are user upgradeable through the YSI web site, making it easy to take advantage of future software improvements.

The YSI 5100 features a built-in barometer, programmable auto-stabilization, membrane integrity function, bar code compatibility, and real-time clock. The full-featured 5100 instrument offers even greater performance and flexibility with one-button auto calibration and built-in SOUR software to meet U.S. EPA 503 regulations for safe use of biosolids. OUR (Oxygen Uptake Rate) and SOUR (Specific Oxygen Uptake Rate) are also valuable process control tools because they indicate the biological activity of microorganisms used in treatment.

If you're interested in dissolved oxygen measurements in the field, please take a look at our NEW Professional Series products Pro20 or optical DO handheld ProODO.


  • Menu-driven software
  • Dissolved oxygen and temperature measurement
  • Large LCD display
  • Automatic calibration
  • 100 data-point memory with date/time stamp


Please visit our extensive dissolved oxygen resource page to learn about all things DO and BOD related;

You can also download The Dissolved Oxygen Handbook - the definitive guide to all things DO.

Related Products

YSI Professional Plus Shown with Single Parameter Cable and Probe Assembly

Professional Plus
YSI ProODO Measuring Dissolved Oxygen in Aquaculture

YSI Pro20 Lab or Field Dissolved Oxygen Meter

YSI BOD Analyst Pro Screen Shot

BOD Analyst Pro™






YSI 5000 and YSI 5100 Instrument General Specifications

Compatible Sensors YSI 5010 BOD Probes
YSI 5905 BOD probes with the 5011 adapter.
Dimensions Size 9 by 9.5 by 4.4 in (22.9 by 24.1 by 11.2 cm)
Weight 2.6 lbs (1.1 kg) with batteries
Operating Environment 0 to +45 °C, 10 to 90% relative humidity, non-condensing
Power The Model 5000 & 5100 are powered by an AC adapter or 4 C-size alkaline batteries.
A new set of alkaline batteries will power the selected instrument for approximately 30 hours (not including stirring).
Salinity Compensation Range 0.0 to 40.0 ppt
Accuracy ±.02 mg/L
Temperature Compensation The mg/L mode is automatically temperature-compensated to an accuracy of ±1% of DO readings between 0 and 5°C, and to an accuracy of ±0.6% of readings between 5 and 45°C.

The % air saturation mode is automatically temperature-compensated to an accuracy of ±0.5% of calibration values between 0 and 5°C, and to an accuracy of ±0.3% of values between 5 and 45°C.
Water Resistance The Model 5000 and 5100 are designed exclusively for indoor use and are NOT waterproof.
Warranty 2-year instrument


YSI 5000 and YSI 5100 Specifications (Instrument Only)

Range Accuracy Resolution
Barometric Pressure 450 to 825 mmHg (600 to 1100 mbar) ±1% plus 1 LSD within ±10°C ambient temperature from calibration point 1 mmHg
Dissolved Oxygen (%) 0.0 to 600.0% air saturation ±0.1% plus 1 Least Significant Digit (LSD) 0.1% air saturation
Dissolved Oxygen (mg/L) 0.0 to 60.0 mg/L ±0.1% plus 1 LSD 0.1%, or 0.01 mg/L , whichever is greater
Dissolved Oxygen (mbar) 0 to 1500 ±1% plus 1 LSD 1 mbar
Temperature -5.0 to +50.0°C ±0.1°C 0.01°C



Probe Specifications for:
YSI 5010
YSI 5905

Dissolved Oxygen Accuracy ± 0.1 mg/L or ± 2% of reading, whichever is greater
Electrolyte KCl with NA2SO4
Membrane Material FEP Fluoropolymer Film Cap
Polarizing Voltage 0.8 volts
Response Time Typical response to a step change in dissolved oxygen at 20°C is 90% of the change in 30 seconds.
Sensor Materials Cathode Gold
Anode Silver
Temperature Accuracy + 0.2°C
Operating  Range 0° to 45°C
Warranty 1-year

YSI 5906 Screw-On Dissolved Oxygen Cap Membrane Kit

5906 DO Cap Membrane Kit

YSI 5906 screw-on cap dissolved oxygen membranes.





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