McMaster-Carr logo
    Filter by
    Maximum Automatic Temperature Compensation (ATC)
    Display Type
    Cable Length
    Maximum Oxidation Reduction Potential (ORP)
    Minimum Oxidation Reduction Potential (ORP)
    Oxidation Reduction Potential (ORP) Resolution
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    Material
    DFARS Specialty Metals
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Digit Height
    Battery Size
    Range Type
    Sensor Material
    pH Resolution
    Maximum Conductivity
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Comments
    E-mail address (if you would like a response)
    19 Products

    ORP Meters

    Measure a solution’s oxidation reduction potential (ORP) to determine its ability to break down contaminants. These meters are commonly used to monitor water quality in pools, spas, and other clean liquids. Use a Calibration Solution (not included) and the calibration adjustment screw to maintain accuracy.
    For Testing Oxidation Reduction Potential (ORP)
    Image of Product. Front orientation. Chemistry Meters. ORP Meters .
    Cannot Be Sold to Canada—Meters cannot be sold to Canada due to import regulations.
    Oxidation Reduction
    Potential (ORP)
    Sensor
    Material
    Range, mV
    Accuracy
    Ht.
    Wd.
    Dp.
    Batteries
    Included
    Cannot Be
    Sold To
    Display
    Type
    Each
    For Use With Dirty Liquids
    Plastic-999 to 999±2 mV7"1 1/2"1 1/2"YesCanadaLCD00000000000000
     

    Water-Resistant ORP Meters

    Since this oxidation reduction potential (ORP) meter has a housing that meets IP67 for complete resistance to dust and protection from temporary submersion, it’s often used to determine a solution’s ability to break down contaminants in harsh field conditions. For use with dirty liquids containing heavy metals, sulfides, and harsh chemicals, this meter is often used for wastewater treatment. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration button to maintain accuracy.
    For Testing Oxidation Reduction Potential (ORP)
    Image of Product. Front orientation. Chemistry Meters. Water-Resistant ORP Meters .
    Cannot Be Sold to Canada—Meters cannot be sold to Canada due to import regulations.
    Oxidation Reduction
    Potential (ORP)
    Sensor
    Material
    Range, mV
    Accuracy
    ATC Range,
    ° F
    Enclosure
    Rating
    Certification
    Ht.
    Wd.
    Dp.
    Batteries
    Included
    Cannot Be
    Sold To
    Display
    Type
    Each
    For Use With Dirty Liquids
    Glass-1,000 to 1,000±2 mV32 to 140IP67
    CE Marked
    8"4"3"YesCanadaLCD000000000000000
     
    Replacement Sensors

    Remote-Reading Multifunction Chemistry Meters

    Take multiple water-chemistry and temperature measurements in hard-to-reach places from up to 3 feet away. Often used in tap water and wastewater, these meters work in both clean and dirty liquids. Automatic temperature compensation standardizes readings to 77° F to prevent inaccurate results in changing temperatures. The data hold function freezes the current reading on the display. For easy viewing, temperature and chemistry measurements appear on the same screen. These meters are IP57 rated, so they resist dust and withstand temporary submersion.
    To maintain their accuracy, all have a calibration button and some also come with calibration solutions.
    For Testing Oxidation Reduction Potential (ORP), pH, and Temperature
    Image of Product. Front orientation. Chemistry Meters. Remote-Reading Multifunction Chemistry Meters , For Testing Oxidation Reduction Potential (ORP).
    Oxidation reduction potential (ORP), pH, and temperature meters take three measurements. ORP measures the amount of dissolved oxygen in liquids. It determines how efficiently a liquid breaks down contaminants.
    Cannot Be Sold to Canada—Meters cannot be sold to Canada due to import regulations.
    Oxidation Reduction
    Potential (ORP)
    pH
    Range, mV
    Accuracy
    Range,
    pH
    Accuracy
    Temp.
    Accuracy
    ATC Range,
    ° F
    Enclosure
    Rating
    Certification
    Ht.
    Wd.
    Dp.
    Batteries
    Included
    Cannot Be
    Sold To
    Display
    Type
    Each
    For Use With Clean and Dirty Liquids
    -1,000 to 1,000±0.2%0 to 14±0.01 pH±0.9° F32 to 212IP57
    CE Marked
    7 1/2"3 9/16"1 5/16"YesCanadaLCD00000000000000
     
    Replacement Sensors

    Water-Resistant Multifunction Chemistry Meters

    Test different water-chemistry measurements in dirty, wet conditions. Often used in pools and spas, all of these meters are for use with clean liquids. They meet IP57 for protection from dust and temporary submersion in liquids. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a calibration solution (not included) and the calibration button to maintain accuracy.
    For Testing Chlorine, Oxidation Reduction Potential (ORP), and pH
    Image of Product. Front orientation. Chemistry Meters. Water-Resistant Multifunction Chemistry Meters .
    Chlorine, oxidation reduction potential (ORP), and pH meters come with three sensors that each take one chemistry measurement.
    Cannot Be Sold To—Import regulations restrict sales to the listed areas.
    Oxidation Reduction
    Potential (ORP)
    pH
    Sensor
    Material
    Range, mV
    Accuracy
    Range,
    pH
    Accuracy
    ATC Range,
    ° F
    Enclosure
    Rating
    Certification
    Ht.
    Batteries
    Included
    Cannot Be
    Sold To
    Display
    Type
    Each
    For Use With Clean Liquids
    Glass-999 to 999±1 mV0 to 14±0.01 pH23 to 194IP57
    CE Marked
    6 7/8"YesCanadaLCD00000000000000
     
    Replacement Sensors

    Multifunction Chemistry Controllers

    Image of Product. Front orientation. Multifunction Chemistry Controllers. LCD Display.
    Image of Product. Front orientation. Multifunction Chemistry Controllers. LCD Display, Washdown Environments.

    LCD Display

    Washdown Environments

    LCD Display

    Image of Product. Front orientation. Multifunction Chemistry Controllers. LED Display.
    Image of Product. Sensor. Front orientation. Chemistry Sensors.

    LED Display

    Sensor

    The same controller can actuate equipment based on pH or oxidation reduction potential (ORP). Using two SPDT (single pole, double throw) relays, these controllers can turn pumps, valves, and other equipment on or off when a reading reaches the actuation point. They also send output signals to a PLC or other receiving device to record data and control equipment. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. These controllers are often used for water treatment, electroplating, and chemical processing.
    They require a pH or ORP sensor (sold separately).
    LED Display—Controllers with an LED display are more visible in low-light conditions than those with an LCD display.
    Washdown Environments—Controllers for washdown environments are rated IP65 for protection against low-pressure washdowns and dust.
    Controllers
    pH Sensors
    ORP Sensors
    pH
    Oxidation Reduction
    Potential (ORP)
    No. of Control
    Relays
    Switch
    Designation
    Mechanical Relay Switching
    Current @ Voltage
    Analog Output
    Current
    Range,
    pH
    Accuracy
    Range, mV
    Accuracy
    Input Voltage,
    V AC
    Mount
    Type
    For DIN Panel
    Cutout Size
    Ht.
    Wd.
    Dp.
    Enclosure
    Rating
    Each
    Each
    Each
    LCD Display
    2SPDT
    5 amp @ 120V AC
    2.5 amp @ 240V AC
    4 mA to 20 mA0 to 14±0.05 pH-1,999 to 1,999±0.5%120
    240
    Panel1/43 3/4"3 3/4"4 3/4"00000000000000000000000000000000000000000000000
     
    LCD Display—For Washdown Environment
    2SPDT
    5 amp @ 120V AC
    2.5 amp @ 240V AC
    4 mA to 20 mA-2 to 16±0.17 pH-2,500 to 2,500±0.1%120
    240
    Panel1/43 3/4"3 3/4"6 5/8"IP65
    000000000000000000000000000000000000000000000
     
    LED Display
    2SPDT
    5 amp @ 120V AC
    2.5 amp @ 240V AC
    4 mA to 20 mA0 to 14±0.05 pH-1,999 to 1,999±0.5%120
    240
    Panel1/43 3/4"3 3/4"4 3/4"00000000000000000000000000000000000000000000
     

    Easy-Read Bench-Top Multifunction Chemistry Meters

    Don’t strain your eyes reading a scale—these bench-top meters indicate exact results on the digital display. For complete resistance to dust and protection from temporary submersion, these meters float and have a housing that meets NEMA 6 and IP67. They're for use with water and other clean liquids. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration button to maintain accuracy.
    For Testing Conductivity, Oxidation Reduction Potential (ORP), pH, Resistivity, and Total Dissolved Solids (TDS)
    Image of Product. Front orientation. Chemistry Meters. Easy-Read Bench-Top Multifunction Chemistry Meters .
    Cannot Be Sold To—Import regulations restrict sales to the listed areas.
    Conductivity
    Resistivity
    Oxidation Reduction
    Potential (ORP)
    pH
    Total Dissolved
    Solids (TDS)
    Sensor
    Material
    Range
    Accuracy
    Range
    Accuracy
    Range, mV
    Accuracy
    Range,
    pH
    Accuracy
    Range
    Accuracy
    ATC Range,
    ° F
    Enclosure
    Rating
    Certification
    Ht.
    Wd.
    Dp.
    Batteries
    Included
    Cannot Be
    Sold To
    Display
    Type
    Each
    For Use With Clean Liquids
    Glass0 to 9,999 μS
    10 to 200 mS
    ±1%10 kohm to 30 Mohm±1%-999 to 999±1 mV0 to 14±0.01 pH0 to 9,999 ppm
    10 to 200 ppt
    ±1%32 to 160IP67, NEMA 6
    CE Marked
    2 1/2"2 3/4"7 3/4"YesCanadaLCD000000000000000
     
    Replacement Sensors
    back to top