Water-Quality Meters | McMaster-Carr

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45 Products

Water-Resistant Multifunction Chemistry Meters

For Use with
Clean
Liquids

For Use
with Clean
and Dirty Liquids

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. 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.

IP57 meters are protected from dust and temporary submersion in liquids.

IP65 meters are protected from dust and low-pressure jets of liquids.

Chlorine, oxidation reduction potential (ORP), and pH meters come with three sensors that each take one chemistry measurement. They cannot be sold to Canada due to import regulations.

Conductivity, salinity, and total dissolved solids (TDS) meters come with one sensor that takes all three chemistry measurements.

Conductivity and total dissolved solids (TDS) meters come with one sensor that takes both chemistry measurements. You can also use them in aquaculture solutions, wastewater, and other dirty liquids.

Import regulations restrict sales to the listed areas.

For Testing Chlorine, Oxidation Reduction Potential (ORP), and pH

For Use With Clean Liquids
Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each
Glass	23° F to 194°	IP57	CE Marked	Yes	Canada	0000000	0000000

Replacement Sensor for Testing pH	Each	000000
Replacement Sensor for Testing Chlorine	Each	000000
Replacement Sensor for Testing Oxidation Reduction Potential (ORP)	Each	00000

For Testing Conductivity, Salinity, and Total Dissolved Solids (TDS)

Meters								Replacement Sensors
Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Nonglass	32° F to 149°	IP57	CE Marked	Yes	Canada	00000000	0000000	00000000	000000

For Testing Conductivity and Total Dissolved Solids (TDS)

For Use With Clean and Dirty Liquids
Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each
Nonglass	32° F to 122°	IP65	CE Marked	Yes	Canada	0000000	000000

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.

Import regulations restrict sales to the listed areas.

Meters									Replacement Sensors
For Testing	Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Conductivity, Resistivity, Total Dissolved Solids (TDS)	Nonglass	32° F to 160°	IP67, NEMA 6	CE Marked	Yes	Canada	000000	000000000	000000	00
Conductivity, Oxidation Reduction Potential (ORP), pH, Resistivity, Total Dissolved Solids (TDS)	Glass	32° F to 160°	IP67, NEMA 6	CE Marked	Yes	Canada	000000	00000000	000000	0000000

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. They cannot be sold to Canada due to import regulations.

To maintain their accuracy, all have a calibration button and some also come with calibration solutions.

Conductivity, salinity, temperature, and total dissolved solids (TDS) meters take four measurements at once. Conductivity measures the concentration of salts, nutrients, chemicals, and other substances. Salinity measures the amount of dissolved salts. TDS determines the contaminant levels. The stainless steel sensor is durable and resists breaking.

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.

For Testing Conductivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

For Testing Conductivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

Conductivity		Salinity			Total Dissolved Solids (TDS)
Range	Accuracy	Range	Accuracy	Temp. Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
0 to 19.99 µS 20 to 199.9 µS 200 to 1,999 µS 2 to 19.99 mS 20 to 199.9 mS	±1% ±1% ±1% ±1% ±1%	0 to 100 ppt	±1%	±0.9° F	0 to 0.1 ppm	±1%	32° F to 212°	Yes	Canada	0000000	0000000

For Testing Oxidation Reduction Potential (ORP), pH, and Temperature

Oxidation Reduction Potential (ORP)		pH
Range	Accuracy	Range	Accuracy	Temp. Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
-1,000 to 1,000 mV	±0.2%	0.0 to 14.0 pH	±0.01 pH	±0.9° F	32° F to 212°	IP57	CE Marked	Yes	Canada	0000000	0000000

Replacement Sensors

For Testing		Each
Conductivity, Salinity, Temperature, Total Dissolved Solids (TDS)	0000000	0000000
Oxidation Reduction Potential (ORP)	0000000	000000
pH	0000000	000000

Bench-Top Multifunction Chemistry Meters

Check the pH and conductivity of water and other clean liquids with one bench-top device. This meter has automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration knob to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters
	pH		Conductivity										Replacement Sensors
Sensor Material	Range	Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, ° F	Ht.	Wd.	Dp.	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Glass	2-12 pH	±0.2 pH	0 to 10 µS 0 to 100 µS 0 to 1,000 µS 0 to 10,000 µS	±2%	50° to 160°	4"	3 1/2"	4 1/2"	Yes	Canada	00000000	0000000	00000000	0000000

Remote-Reading Multifunction Chemistry Meters with PC Output

Test temperature, chemical concentration, contamination, and salt levels in liquid from up to 6 ft. away, then send the results to your computer for analysis. These meters include a USB cable that transfers up to 1,000 readings. Often used to test water quality, they work on both clean and dirty liquids—from tap water to wastewater. Conductivity tests measure the concentration of salts, nutrients, chemicals, and other substances. Total dissolved solids (TDS) tests report contaminant levels. Salinity tests determine the salt levels in liquid. The sensor is made of stainless steel, so it’s durable and resists breaking. IP67 rated, these meters are dust tight and withstand temporary submersion.

To prevent inaccurate results from changing temperatures, these meters automatically standardize temperature readings at 77° F. Temperature readings appear on screen with other measurements, so you won’t have to scroll through multiple screens. A data hold function freezes the current reading on the display.

To maintain accuracy of the meters, they come with calibration solutions and have a calibration button.

These meters cannot be sold to Canada due to import regulations.

For Testing Conductivity, Resistivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

Meter

Conductivity		Resistivity		Salinity			Total Dissolved Solids (TDS)
Range	Accuracy	Range	Accuracy	Range	Accuracy	Temp. Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
0 to 200 mS	±1.5%	0 to 20 megohms	±1.5%	0 to 100 ppt	±1.5%	±0.9° F	0 to 100 ppt	±0.1%	32° to 212°	Yes	Canada	00000000	0000000

Replacement Sensors

Replacement Sensor

For Testing		Each
Conductivity, Resistivity, Salinity, Temperature, Total Dissolved Solids (TDS)	00000000	0000000

Water-Resistant pH Meters

Check pH in harsh field conditions. These floating meters that have a housing that meets IP67 for complete resistance to dust and protection from temporary submersion. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a calibration solution and the calibration button to maintain accuracy. They do not include Calibration Solution. Meters cannot be sold to Canada due to import regulations.

Meter for clean liquids is commonly used in pools and hydroponic solutions.

Meter for dirty liquids stands up to wastewater, plating bath solutions, and other harsh liquids.

Meters
	pH									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Glass	0 to 14 pH	±0.1 pH	32° to 122°	IP67	CE Marked	Yes	Canada	00000000	0000000	000000	00
For Use With Dirty Liquids
Glass	-2 to 16 pH	±0.01 pH	32° to 122°	IP67	CE Marked	Yes	Canada	00000000	000000	00000000	000000

pH Meters

More precise than test strips, these meters are often used to measure the pH of dirty liquids in agricultural systems, aquaculture tanks, and printing fountains. 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. Meters cannot be sold to Canada due to import regulations.

	pH
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Dirty Liquids
Glass	0 to 14 pH	±0.1 pH	32° to 122°	Yes	Canada	0000000	000000

Remote-Reading pH Meters

Monitor pH readings from your smartphone or tablet—download the app to view data up to 160 ft. away using Bluetooth. Made of durable nonglass, the sensor resists breaking. They are for use with dirty liquids, so they stand up to petrochemical, environmental, and agricultural testing. Rated IP67, they seal out dust and withstand temporary submersion. Use a calibration solution (not included) and the calibration setting in the app to maintain accuracy.

These meters cannot be sold to Canada due to import regulations.

Meters
	pH										Replacement Sensors		Calibration Solutions
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Data Connection Type	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each		Each
For Use With Dirty Liquids
Nonglass	0 to 14 pH	±0.02 pH	32° to 176°	Bluetooth	IP67	CE Marked	Yes	Canada	0000000	000000000	0000000	0000000	000000000	000000

Remote-Reading pH Meters with PC Output

Meter

LCD Display

Transmit pH readings to a PC for analysis. These meters have a sensor on a 6-ft. cable for taking remote readings of water and other clean liquids. They have automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate readings in fluctuating temperatures. Use the included calibration solution and calibration button to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters
	pH								Replacement Sensors
Sensor Material	pH Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Nonglass	-2 to 16 pH	±0.01 pH	-22° F to 260°	CE Marked	Yes	Canada	00000000	0000000	000000000	0000000

Water-Resistant Conductivity Meters

Don’t worry about dropping this meter in your tank when checking electrical conductivity—it floats and has a housing that meets IP67 for complete resistance to dust and protection from temporary submersion. For use with water, hydroponic solutions, and other clean liquids, this meter measures a liquid's conductivity to indicate the concentration of salts, nutrients, chemicals, and other substances. It displays temperature in addition to conductivity. 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.

Import regulations restrict sales to the listed areas.

Meters
	Conductivity									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
304 Stainless Steel	0 to 1,999 µS	±1.5%	32°F to 122°	IP67	CE Marked	Yes	Canada	00000000	0000000	00000000	000000

Bench-Top Conductivity Meters

Pour contaminated water, wastewater, printing fountain solutions, and other dirty liquids into the meter cup to test electrical conductivity levels that indicate the concentration of salts, nutrients, chemicals, and other substances. These meters have automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration knob to maintain accuracy.

	Conductivity
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, ° F	Ht.	Wd.	Dp.	Batteries Included		Each
For Use With Dirty Liquids
Nonglass	0 to 0.5 µS 0 to 5 µS 0 to 50 µS 0 to 500 µS 0 to 5,000 µS	±2%	32° to 120°	4"	3 1/2"	4 1/2"	Yes	0000000	0000000
Nonglass	0 to 10 µS 0 to 100 µS 0 to 1,000 µS 0 to 10,000 µS	±2%	50° to 160°	4"	3 1/2"	4 1/2"	Yes	00000000	000000

Optional Carrying Case

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Each

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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. Meters cannot be sold to Canada due to import regulations.

	Oxidation Reduction Potential (ORP)
Sensor Material	Range	Accuracy	Batteries Included	Cannot Be Sold To		Each
For Use With Dirty Liquids
Nonglass	-999 to 999 mV	±2 mV	Yes	Canada	0000000	0000000

Water-Resistant TDS Meters

Since these meters float and have a housing that meets IP67, they won’t be damaged by temporary submersion and have complete resistance to dust. They detect total dissolved solids (TDS) in water, hydroponic solutions, and other clean liquids to determine contaminant levels. 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.

Import regulations restrict sales to the listed areas.

Meters
	Total Dissolved Solids (TDS)									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
304 Stainless Steel	0 to 1,000 ppm	±1.5%	32° to 122°	IP67	CE Marked	Yes	Canada	00000000	0000000	00000000	000000

Bench-Top TDS Meters

Commonly used to test environmental samples, boiler condensate, wastewater, and other dirty liquids for contaminants, this bench-top meter determines the total dissolved solids (TDS) in a solution. It has automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration knob to maintain accuracy.

	Total Dissolved Solids (TDS)
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, ° F	Ht.	Wd.	Dp.	Batteries Included		Each
For Use With Dirty Liquids
Nonglass	0 to 50 ppm 0 to 500 ppm 0 to 5,000 ppm	±2%	50° to 160°	4"	3 1/2"	4 1/2"	Yes	0000000	0000000

Carrying Cases for Bench-Top Conductivity and TDS Meters

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Each

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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. Meters cannot be sold to Canada due to import regulations.

Meters
	Oxidation Reduction Potential (ORP)									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Dirty Liquids
Glass	-1,000 to 1,000 mV	±2 mV	32° to 140°	IP67	CE Marked	Yes	Canada	00000000	0000000	00000000	0000000

Water-Resistant Dissolved Oxygen Meters

Check the oxygen levels of water and other clean liquids in harsh field conditions. This meter has a housing that meets IP57 for good resistance to dust and protection from temporary submersion. It has automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use distilled water and the calibration button to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters
	Dissolved Oxygen									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Nonglass	0 to 20 ppm	0.4 ppm	32° F to 122°	IP57	CE Marked	Yes	Canada	00000000	0000000	00000000	0000000

Sanitary Conductivity Sensors

Sensor

Three-Color Display

Optional Quick-Clamp Adapter

Often used to save rinse water in beverage and pharmaceutical lines, these sensors test the amount of chemicals, cleaners, and other substances in liquids by measuring how well the liquid conducts electricity. They’re 3-A and European Hygienic Engineering and Design Group (EHEDG) certified, thanks to their design that’s easy to keep clean. Highly polished, they limit where bacteria could grow. They also withstand washdowns with hot water, chemicals, and cleaners common to sanitary lines because of their PEEK probe, stainless steel body, and IP ratings. Their IP ratings also mean they’re dust tight and won’t fail if briefly under water. All are FDA compliant to safely touch food.

These sensors work with 4-20 mA analog output to connect to remote displays and programmable logic controllers (PLCs), making them good for hard-to-reach areas and frequent application changes. This also means they’ll set off alarms and trigger cycles to start and stop in automated systems. With the touchscreen, program each color of the display to alert you to errors, completed cycles, and other events. Both the head and the display rotate to view readings from the best angle.

Highly accurate, these sensors test almost any liquid. They also measure temperature—no need for a separate sensor. To compare readings as temperature changes, they automatically standardize readings at 77° F. All meet European safety standards, since they’re CE marked.

Use quick-clamp adapters to connect these sensors to quick-clamp sanitary tube fittings.

Import regulations restrict sales to the listed areas.

For technical drawings and 3-D models, click on a part number.

	Sensor			Conductivity
Lg., mm	Material	Dia., mm	Lg., mm	Range	Accuracy	Electrical Connection Type	Pipe Size	Thread Type	Gender	Automatic Temp. Compensation (ATC) Range, °F	Environmental Rating	Specifications Met		Each
For Use With Liquids
37	PEEK Plastic	3.6	26	0 to 1,000 mS 0 to 500 mS 0 to 500 µS	±1.5% ±1% ±1.5%	Threaded M12 Plug (Two 4-Pole Connections)	1	BSPP	Male	-4° to 302°	IP67, IP69K	3-A Certified 74-07, CE Marked, EHEDG Certified, FDA Compliant 21 CFR 177.2415	0000000	000000000
60	PEEK Plastic	3.6	26	0 to 1,000 mS 0 to 500 mS 0 to 500 µS	±1.5% ±1% ±1.5%	Threaded M12 Plug (Two 4-Pole Connections)	1	BSPP	Male	-4° to 302°	IP67, IP69K	3-A Certified 74-07, CE Marked, EHEDG Certified, FDA Compliant 21 CFR 177.2415	0000000	00000000

Optional Quick-Clamp Adapter

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Each

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