Multiparameter Sondes

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6600 V2

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600OMS V2

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CastAway CTD

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AquaViewer App

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Pro1020 Field DO/pH/ORP

Pro1030 Field pH/ORP/Cond

Pro2030 Field DO/Cond

Pro30 Field Cond

Classic Handheld Series

556MPS Multiparameter

550A Dissolved Oxygen

63 pH/Conductivity

60 pH

58 Lab/Field DO

55 Dissolved Oxygen

Colorimeters

900 Chlorine

910 COD

pHotoFlex Colorimeters

Laboratory Series

pH1200

5000/5100 BOD/DO

3200 Conductivity

3100 Conductivity

MultiLab 4010-1

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TruLab 1110

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TruLab 1320 and 1320P

EcoSense

pH10A - pH Pen

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DO200A - DO

EC30A - Conductivity Pen

EC300A - Conductivity

9300/9500 Photometer

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Ammonia/Ammonium

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Chloride

Chlorophyll

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Dissolved Oxygen

Free Chlorine

Level

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pH

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pH

pH determines the acid and base characteristics of water. A pH of 7.0 is neutral; values below 7 are acidic and values above 7 are alkaline. Excessively high or low pH levels are often associated with nutrient deficiencies, metal toxicities, or other problems for aquatic life. High pH makes ammonia more toxic. During algal blooms, photosynthesis increases the water pH, especially in stagnant or slow-moving water.

YSI pH1200 Laboratory pH Meter
YSI pH1200 Laboratory pH MeterYSI pH1200 Laboratory pH Meter YSI MultiLab 4010-3 with Three SensorsYSI MultiLab 4010-3 with Three Sensors YSI 6561 pH Sensor with guard for 6-Series sondes.YSI 6561 pH Sensor with guard for 6-Series sondes.

 

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YSI has Authorized Distributors all over the globe. View a map and find your closest contact for YSI pH products and accessories.

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Have a question about your YSI pH product? Check out the support page with resources compiled just for you.

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Product Service Centers

Want to return a product for service? Here you’ll find authorized service centers and instructions on how to send in your YSI pH product.

Product Service

pH is measured by a sensing electrode for Hydrogen and a reference electrode along with a meter to measure the electrode potential. The YSI pH sensor is a glass bulb filled with a solution of stable pH (usually 7), so the inside of the glass surface experiences constant binding of H+ ions. The outside of the bulb is exposed to a water sample where H+ varies. The resulting differential of H+ creates a potential which is read by the meter versus the stable potential of the reference electrode.

Presentation: How to Make Good pH Measurements
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Blog Posts of Interest

Extend the Life of Your pH Electrode in 3 Practical Steps

pH Meter Calibration Problems? Check Out These 12 Tips!

Making Better pH Measurements and How to Improve pH Data Quality

Manuals

TruLab Model 1320 & 1320P Operations Manual

TruLab Model 1310 & 1310P Operations Manual

TruLab Model 1110 Operations Manual

IQ SensorNet SensoLyt Sensor User Manual

IQ SensorNet SensoLyt Combination Sensors User Manual

pH1200 Operations Manual

pH1200 Operations Manual - Español

pH1200 Operations Manual - Portuguese

Guides

6-Series pH Sensors Overview

Feed Smart Feed Timer Overview

FAQs - Frequently Asked Questions

YSI EcoSense FAQs

Tips

6-Series Sonde Calibration, Maintenance & Troubleshooting Tips

Professional Plus Handheld Calibration Tips

Specification Sheets

TruLab pH/ISE 1320 & 1320P Laboratory Meters

TruLab pH 1310 & 1310P Laboratory Meters

TruLab pH 1110 Laboratory Meter

MultiLab 4010-1, 4010-2 and 4010-3 Laboratory Meters

YSI Pro1020 Dissolved Oxygen, pH or ORP Meter Specification Sheet

YSI pH1200 Laboratory pH and mV Instrument

YSI Pro1030 pH/ORP/Conductivity Meter

YSI 5200A Continuous System Monitor Specifications

YSI Professional Plus Water Quality Meter Specifications

Français - YSI Professional Plus qualité de l'eau Spécifications de l'instrument

Español - YSI Professional Plus de Calidad del Agua de instrumentos Especificaciones

YSI IQ SensorNet 182, 182 XT, 182 XT-4 Specifications Sheet

YSI IQ SensorNet 2020 XT Specifications Sheet

Fast-Response pH Sensor

Catalogs & Brochures

IQ SensorNet Wastewater Process Monitoring & Control Catalog

Aquaculture Monitoring & Control

YSI Vertical Profiling Systems

Application Notes

Watching the Watershed

IQ SensorNet and SCADA Combined to Reduce Costs and Improve Effluent

Network Monitors Water Quality in Shale Gas Drilling Region

Water Quality Is Key to the Success of Cardiff Bay Restoration

Understanding Ammonia in Aquaculture Pond Systems

Managing and Protecting Remote Source Water for the East Bay Area

Handheld Professional Plus Instrument Saves Time Measuring Ammonia in Aquaculture Ponds

Español - El portátil Professional Plus ahorra tiempo cuando no hay tiempo que perder

Pontoon-Mounted Autonomous Monitoring System Keeps Constant Watch on Harmful Algal Blooms

Technical Notes

Soil Sample Analysis for pH: Methods to Determine Soil pH with the EcoSense pH100

Cleaning and Reconditioning Instructions for pH100, 60/63 pH, 5564 pH and 5565 pH/ORP Probes

Cleaning and Reconditioning Instructions for the 6561 and 6031 pH, 6032 ORP, and 6565 pH/ORP Probes

YSI pH Sensor Performance

Care, Maintenance, and Storage of YSI 6-Series Probes and Sondes

MSDS

3823 Buffer Solution pH 10.00

3821 Buffer Solution pH 4.00

YSI 6600V2 Comprehensive Monitoring System - View of Sensor Configuration
 

6600V2

Make the most of your environmental monitoring.

 

The YSI 6600 V2 data sonde is the most comprehensive water quality monitoring equipment available with simultaneous measurement of conductivity (salinity), temperature, depth or level, pH/ORP plus...

 

YSI 6920 V2-2 sensor view showing Temperature/Conductivity, Chloride, pH, as well as Optical DO and Turbidity.
 

6920 V2

Compact Data Sonde for Unattended Monitoring

 

The YSI 6920 V2 sonde is an economical water quality logging system, ideal for long-term in situ monitoring and profiling.

Real-time turbidity monitoring, dissolved oxygen monitoring, algae monitoring, and more.

 

YSI 6820 V2 showing sensors, starting clockwise from top: ROX Optical Dissolved Oxygen, Turbidity, pH, ISE, and temperature/condutivity.
 

6820 V2

Compact Sonde for Field Sampling

 

The YSI 6820 V2 is a cost-effective data sonde for profiling and spot-checking water quality in rivers, lakes, wetlands, wells, estuaries, and coastal waters.

     

    YSI 600XLM V2 shown without probe guard.
     

    600XL V2 and 600XLM V2

    Small Packages - Economical Sampling or Logging


    Both the YSI 600XL V2 (sampling) and the YSI 600XLM V2 (logging) data sondes offer economical solutions in small packages for surface water and ground water applications. Both models easily fit into 2-inch wells and measure a range of fundamental parameters, including oxygen - with the YSI ROX™ optical dissolved oxygen sensor - and level, using a highly-accurate vented sensor.

     

    The YSI 6600EDS showing Turbidity (center) with attached wiper brush, Clockwise from top: Chlorophyll, pH/ORP, Temperature/Conductivity, and Rapid Pulse Dissolved Oxygen Sensors.
     

    6600EDS

    Extended Deployment for Harsh Environments

     

    The 6600EDS multiparameter sonde accurately measures 10 parameters in severe fouling environments for extended periods. The sonde has two optical ports, conductivity/temperature port, Rapid Pulse DO port, and pH/ORP port. The 6600EDS also offers an extended brush that cleans the pH/ORP and Rapid Pulse DO sensors.

     

    YSI 600QS 'Quick Sample'
     

    600QS

    The Quick Solution to Handheld Sampling

     

    Combined for convenience, the YSI 650 MDS display-datalogger and the YSI 600R sonde allow you to collect 11 parameters simultaneously in real time.

     

    YSI 600R shown with probe guard attached.
     

    600R

    Water Quality Sampling Sonde

     

    The YSI 600R provides water quality sampling in a small package for surface water and ground water applications. With a diameter of less than two inches (4.2 cm), the 600R easily fits into wells.

     

    YSI 6920DW showing sensors, clockwise from top: pH/ORP, Temperature/Conductivity, Free Chlorine, Turbidity.
     

    6920DW

    Monitor Drinking Water in Distribution System

     

    The YSI 6920DW is a portable instrument which measures free chlorine, turbidity, and other parameters. Take readings at multiple points along a drinking water distribution system; the collected data gives you a comprehensive view of your water quality and can help you detect events of concern.

     

    YSI 600DW-B shown in profile with probe guard removed.
     

    600DW

    Sidestream measurements for distribution systems

     

    The YSI 600DW is a portable instrument which measures free chlorine and other parameters. Take readings at multiple points along a drinking water distribution system; the collected data gives you a comprehensive view of your water quality and can help you detect events of concern.

     

    YSI 6500 Process Monitor
     

    6500 Process Monitor

    Improve Operational Efficiency with Continuous Data

     

    With 8 scalable 4-20 mA current loop channels, 4 SPDT relays, and the ability to continuously monitor dissolved oxygen, conductivity, temperature, and pH via a YSI 6-Series sonde, the YSI 6500 helps you stay one step ahead in data collection.

     

    YSI 5200A Multiparameter Continuous Monitor and Control Instrument
     

    5200A

    Multiparameter Monitoring and Control Instrument

     

    Designed specifically for Aquaculture Systems, the YSI 5200A and AquaManager™ Software integrate process control, alarming, and data management into one product. Simple enough to monitor one tank, powerful enough to manage a full scale farming operation from anywhere in the world. Simultaneously measure dissolved oxygen, pH, conductivity, ORP, salinity and temperature.

     

    YSI Professional Plus Shown with Single Parameter Cable and Probe Assembly
     

    Professional Plus

    Handheld Multiparameter Instrument

     

    The YSI Professional Plus handheld multiparameter meter provides extreme flexibility for the measurement of a variety of combinations for dissolved oxygen, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, pH/ORP combination, ammonium (ammonia), nitrate, chloride and temperature. Also a very powerful lab instrument for BODs, pH and ORP.

     

    YSI Pro1020 Dissolved Oxygen, pH or ORP Meter
     

    Pro1020

    Field dissolved oxygen / pH / ORP

    The Pro1020 provides everything you need in a handheld meter that measures dissolved oxygen and temperature along with either pH or ORP (redox). Rugged, simple and reliable.

    Measure pH or ORP, dissolved oxygen, and temperature.

     

    YSI 556 Handheld Multiparameter Sampling
     

    556MPS

    Handheld Multiparameter Instrument

     

    Rugged, reliable and waterproof, the YSI 556 MPS (Multiprobe System) combines the versatility of an easy-to-use, easy-to-read handheld unit with all the functionality of a multiparameter system.

     

    YSI 4010-1 Laboratory Instrument
     

    MultiLab 4010-1

    Laboratory Instrument for pH, ORP, conductivity and BOD in any combination

    Perform accurate lab pH, ORP, conductivity or BOD measurements with the YSI 4010-1.

     

    YSI MultiLab 4010-3 Laboratory Instrument
     

    MultiLab 4010-2 and 4010-3

    Laboratory Instruments for pH, ORP, conductivity, BOD and ISEs in any combination

    Perform accurate lab pH, ORP, conductivity, BOD or ISE measurements with the YSI 4010-2 or 4010-3 in any combination.

     

    YSI EcoSense pH10A pH Tester
     

    pH10A

    Pen-style pH Tester Instrument

    The pH10A is part of the EcoSense® family of products. It's the perfect instrument for economical spot sampling of pH and temperature in many applications including wastwater, surface water, aquaculture, hydroponics, pools, and education.

     

    YSI EcoSense pH100A pH Meter
     

    pH100A

    Handheld pH or mV Meter

     

    YSI's EcoSense® product line of compact, handheld instruments includes the pH100A pH meter. For simple, one handed operation for pH readings or mV values and temperature the pH100A is a logical choice.

     

    YSI IQ SensorNet 2020 XT Wastewater Monitoring System
     

    IQ SensorNet 2020 XT

    Improve Operational Efficiency with Continuous Data

    With an easily scalable solution, the 2020 XT allows for the connection of up to 20 sensors. This modular plug-and-play system allows you to monitor the water quality in your wastewater system continuously and accurately.

    "The simple cabling infrastructure - being able to run one cable that provides both power and data-transfer made so much sense."

     

    YSI IQ Sensor Net 182 XT Stacked on Modules
     

    IQ SensorNet 182 Models

    Improve Operational Efficiency with Continuous Data

    With an easily scalable solution the 182, 182 XT, and 182 XT-4 allow for the connection of 1-4 sensors depending on which terminal you choose. Add sensors at any time and at any location or change them out with ease. This completely modular plug-and-play system allows you to monitor the water quality in your wastewater or aquaculture system continuously and accurately.

     

    YSI Buoy-Based Vertical Profiling System
     

    Vertical Profilers

    For watersheds, source water and reservoir monitoring, YSI Vertical Profiling Systems provide automated data collection and telemetry throughout a water column. These water quality profilers are available in 3 different deployment configurations, each featuring:

    • Rugged, non-corrosive winch and drive mechanism
    • Software for easy set-up, deployment, water quality analysis and export
    • User-selectable sample intervals

     

    YSI TruLab Model 1110 for pH, mV, ORP in the Laboratory
     

    TruLab 1110

    Laboratory Instrument for pH, mV (ORP) and temperature

    Perform accurate lab pH, mV (ORP) and temperature measurements with the YSI 1110.

     

    YSI TruLab 1310 pH, mV, ORP and Temperature Lab Meter
     

    TruLab 1310 and 1310P

    Laboratory Instrument for pH, mV (ORP) and temperature

    Perform accurate lab pH, mV (ORP) and temperature measurements with the YSI 1310 and 1310P with printer.

     

    YSI TruLab 1320 pH, mV, ORP, ISE and Temperature Lab Meter
     

    TruLab 1320 and 1320P

    Laboratory Instrument for pH, mV (ORP), ISEs and temperature

    Perform accurate lab pH, mV (ORP), ISE and temperature measurements with the YSI 1320 and 1320P with printer.

     

    YSI 5564 pH Sensor for the 556 Instrument
     

    5564 pH Sensor

    pH sensor for the YSI Model 556 instrument

     

    5565 pH and ORP  Sensor for the 556 Instrument
     

    5565 pH & ORP Sensor

    pH and ORP sensor for the YSI Model 556 instrument

     

    YSI Pro Plus BOD pH Lab Kit, US
     

    603166 Pro Plus BOD pH Lab Kit US

    Pro Plus meter, BOD probe, Lab quality pH probe, Lab dock, US power supply

     

    YSI Pro Plus Field Kit, 4-meter, Polarographic DO and pH
     

    603184 Pro Plus 4-Meter Field Kit Polarographic and pH

    Pro Plus meter, 4-meter cable with Polarographic DO probe, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus Field Kit, 10-meter, Polarographic DO and pH
     

    603186 Pro Plus 10-Meter Field Kit Polarographic and pH

    Pro Plus meter, 10-meter cable with Polarographic DO probe, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus Field Kit, 4-meter, Conductivity and pH
     

    603188 Pro Plus 4-Meter Field Kit Conductivity and pH

    Pro Plus meter, 4-meter cable with conductivity built-in, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus Field Kit, 10-meter, Conductivity and pH
     

    603189 Pro Plus 10-Meter Field Kit Conductivity and pH

    Pro Plus meter, 10-meter cable with conductivity built-in, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus Field Kit, 4-meter, Polarographic DO, Conductivity and pH
     

    603190 Pro Plus 4-Meter Field Kit Polarographic DO, Conductivity and pH

    Pro Plus meter, 4-meter cable with conductivity built-in and Polarographic DO probe, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus Field Kit, 4-meter, Galvanic DO, Conductivity and pH
     

    603191 Pro Plus 4-Meter Field Kit Galvanic DO, Conductivity and pH

    Pro Plus meter, 4-meter cable with conductivity built-in and Galvanic DO probe, field pH probe, carrying case, cable management kit

     

    YSI Pro Plus BOD pH Lab Kit, International
     

    603220 Pro Plus BOD pH Lab Kit International

    Pro Plus meter, BOD probe, Lab quality pH probe, Lab dock, International power supplies

     

    YSI Pro Plus Field Kit, 4-meter, Polarographic DO, Conductivity and pH/ORP
     

    603223 Pro Plus 4-Meter Field Kit Polarographic DO, Conductivity, and pH/ORP

    Pro Plus meter, 4-meter cable with conductivity, Polarographic DO probe, field pH, field ORP probe, carrying case, cable management kit

     

     YSI Pro Plus Field Kit, 4-meter, Galvanic DO, Conductivity and pH/ORP
     

    603224 Pro Plus 4-Meter Field Kit Galvanic DO, Conductivity, and pH/ORP

    Pro Plus meter, 4-meter cable with conductivity, Galvanic DO probe, field pH, field ORP probe, carrying case, cable management kit

     

    EcoSense 606110 pH Sensor Replacement
     

    606110 Replacement pH Sensor for the pH10 (gray)

    YSI replacement pH sensor for the pH10A pen-style instrument.

     

    YSI MultiLab Advanced BOD and pH Lab Kit
     

    MultiLab Advanced BOD and pH Lab Kit, 626574

     

    YSI MultiLab BOD and pH Lab Kit
     

    MultiLab BOD and pH Lab Kit, 626573

     

    YSI MultiLab pH Lab Kit
     

    MultiLab pH Lab Kit, 626572

     

    YSI MultiLab Line pH Electrode
     

    pH Electrode, Plastic, 103740Y (1.5 meter cable)

     

    YSI MultiLab Line pH Electrode
     

    pH Electrode, Plastic, 103741Y (3 meter cable)

     

    YSI pH Probe (Guarded Glass Bulb) and Flat-glass pH Probe
     

    pH Sensors (6-Series)

    Simple, accurate pH measurement in sensors designed for minimal maintenance in sampling, profiling, and long-term monitoring applications.

     

    There are no additional images related to pH.

    Measuring pH in polluted water
     

    Making Better pH Measurements in Sampling and Long-Term Monitoring Applications


    Archived Webinar:
    Making Better pH Measurements in Sampling and Long-Term Monitoring Applications


    Original Broadcast: Tuesday, June 7, 2011 —1:00-2:00 PM Eastern Time (US)


    YSI's Mike Lizotte and Tom Moeggenberg present an informative webinar about making accurate pH measurements in sampling and monitoring applications.

    Topics include:
    • Choosing the right sensor for your application
    - Sampling vs. long-term sensor options
    - Glass bulb, flat glass, and hemispherical bulbs
    -  New Amplified pH sensor technology
    -  Replaceable vs. refillable probes
    • How to make good pH measurements
    - Calibration procedures
    - Using millivolts to estimate sensor life and anticipate replacement
    - How to recondition and service a pH sensor
    - Field measurements in Low Ionic Conditions
    - Preventing biofouling on sensors

    Who should attend:
    • Those using submersible field sensors for water quality sampling and monitoring
    • Those measuring pH for water quality concerns, including climate change, ocean acidification, acid mine drainage, aquaculture and fisheries, and NPDES compliance

    Download Slide Presentation: Making Good pH Measurements

     

     

     

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