Water Quality Parameters: MyronLMeters.com

Posted by 15 Apr, 2014

TweetWater Quality Parameters Measuring Key Water Quality Parameters The right meter is essential for measuring any of several key water quality parameters: Conductivity is the ability of water to conduct an electrical current and is an indirect measure of the conductive ionic mineral concentration. The more conductive ions that are present, the more electricity can be […]

Water Quality Parameters

Measuring Key Water Quality Parameters

The right meter is essential for measuring any of several key water quality parameters:

Conductivity is the ability of water to conduct an electrical current and is an indirect measure of the conductive ionic mineral concentration. The more conductive ions that are present, the more electricity can be conducted by the water. This measurement is expressed in microsiemens per centimeter (µS/cm) at 25º Celsius. Myron L Meters carries a complete line of conductivity meters, including the Ultrameter II 4P.

Resistivity is the inverse of conductivity. Electrical conductivity is a measure of water’s resistance to an electric current. Water itself has a weak electrical conductivity. Electric current is transported in water by dissolved ions, making conductivity measurement a quick and reliable way to monitor the total amount of ionic contaminants in water. Myron L Meters carries a complete line of resistivity meters, including inline monitor/controllers like the 753II Resistivity Digital Monitor/Controller. Read more about Measuring Key Water Quality Parameters

The Ultrameter III 9P is the most comprehensive water meter on the market, measuring 9 parameters with a single instrument: Conductivity, Resistivity, TDS, Alkalinity, Hardness, Langelier Saturation Index,
ORP/Free Chlorine, pH, Temperature. Three parameters – LSI, hardness, and alkalinity require titration. Find out more about the Ultrameter III 9P

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Water Quality Parameters: MyronLMeters.com was originally published on Myron L Meters Blog

Categories : Uncategorized

Measuring Key Water Quality Parameters: MyronLMeters.com

Posted by 12 Apr, 2014

TweetThe right meter is essential for measuring any of several key water quality parameters:Conductivity is the ability of water to conduct an electrical current and is an indirect measure of the conductive ionic mineral concentration. The more conductive ions that are present, the more electricity can be conducted by the water. This measurement is expressed […]

The right meter is essential for measuring any of several key water quality parameters:

Conductivity is the ability of water to conduct an electrical current and is an indirect measure of the conductive ionic mineral concentration. The more conductive ions that are present, the more electricity can be conducted by the water. This measurement is expressed in microsiemens per centimeter (µS/cm) at 25º Celsius. Myron L Meters carries a complete line of conductivity meters, including the Ultrameter II 4P.

Resistivity is the inverse of conductivity. Electrical conductivity is a measure of water’s resistance to an electric current. Water itself has a weak electrical conductivity. Electric current is transported in water by dissolved ions, making conductivity measurement a quick and reliable way to monitor the total amount of ionic contaminants in water. Myron L Meters carries a complete line of resistivity meters, including inline monitor/controllers like the 753II Resistivity Digital Monitor/Controller.

Total Dissolved Solids (TDS) is also a measurement of the amount of dissolved minerals in the water. In this instance they would be called solids in solution. The quantity of dissolved solids in the solution is directly proportional to the conductivity. In this case, conductivity is the measurement but it is used to estimate TDS. It is measured with a conductivity meter but is reported as TDS in parts per million (ppm), via a complex algorithm. Myron L Meters carries a complete line of TDS meters, including the Ultrapen PT1.

pH is a measure of the concentration of hydrogen ions in the water, indicating the acidity or alkalinity of the water. On the pH scale of 0-14, a reading of 7 is considered to be neutral. Readings below 7 indicate acidic conditions, while readings above 7 indicate the water is alkaline or basic. Naturally occurring fresh waters have a pH range between 6 and 8. Myron L Meters carries a complete line of pH meters, including the Ultrapen PT2

Temperature is expressed in degrees Celsius (C) or Fahrenheit (F). Most digital handheld Myron L Meters include a temperature function.



Oxidation reduction potential (ORP)can correlate millivolt readings to the sanitization strength of the water. Microbes can cause corrosion, fouling, and disease, and oxidizing biocides are usually used to keep microbial levels under control. ORP is expressed in millivolts (mV). Myron L Meters carries a complete line of ORP meters, including the Ultrapen PT3

Free Chlorine refers to both hypochlorous acid (HOCl) and the hypochlorite (OCl–) ion or bleach, and is commonly added to water systems for disinfection. Free chlorine is typically measured in drinking water disinfection systems to find whether the water system contains enough disinfectant.  Myron L Meters Ultrameter II 6PFCe and Ultrapen PT4 can both be used to measure free chlorine.

Salinity is simply a measure of the amount of salts dissolved in water, a measurement useful to pool service technicians and others.  You can measure salinity with a Myron L Pool Pro PS6.

Alkalinity is a measure of the capacity of water or any solution to neutralize or “buffer” acids. This measure of acid-neutralizing capacity is important in figuring out how “buffered” the water is against sudden changes in pH. Alkalinity is a titration function of the Ultrameter III 9PTKA.

Hardness is caused by compounds of calcium and magnesium, and by a variety of other metals.  As water moves through soil and rock, it dissolves very small amounts of minerals and holds them in solution. Calcium and magnesium dissolved in water are the two most common minerals that make water “hard.” Hardness is a titration function of the Ultrameter III 9PTKA.

LSI or Langelier Saturation Index helps you determine the scaling potential of water. LSI is a calculated number used to predict the calcium carbonate stability of water. It indicates whether the water will precipitate, dissolve, or be in equilibrium with calcium carbonate. LSI is a titration function of the Ultrameter III 9PTKA.

MyronLMeters.com is the premier internet retailer of accurate, reliable Myron L meters.  Save 10% when you order Myron L meters online at MyronLMeters.com. You’ll find reliable instruments for every water quality parameter mentioned above.



 

 

 

Categories : Uncategorized

DEIONIZED WATER APPLICATIONS: MyronLMeters.com

Posted by 11 Apr, 2014

TweetYears ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash.THE DEIONIZATION PROCESSThe vast majority of dissolved impurities in […]

Years ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash.

THE DEIONIZATION PROCESSThe vast majority of dissolved impurities in modern water supplies are ions such as calcium, sodium, chlorides, etc. The deionization process removes ions from water via ion exchange. Positively charged ions (cations) and negatively charged ions (anions) are exchanged for hydrogen (H+) and hydroxyl (OH-) ions, respectively, due to the resin’s greater affinity for other ions. The ion exchange process occurs on the binding sites of the resin beads. Once depleted of exchange capacity, the resin bed is regenerated with concentrated acid and caustic which strips away accumulated ions through physical displacement, leaving hydrogen or hydroxyl ions in their place.

DEIONIZER TYPESDeionizers exist in four basic forms: disposable cartridges, portable exchange tanks, automatic units, and continuous units. A two-bed system employs separate cation and anion resin beds. Mixed-bed deionizers utilize both resins in the same vessel. The highest quality water is produced by mixed-bed deionizers, while two-bed deionizers have a larger capacity. Continuous deionizers, mainly used in labs for polishing, do not require regeneration.

TESTING Dl WATER QUALITYWater quality from deionizers varies with the type of resins used, feed water quality, flow, efficiency of regeneration, remaining capacity, etc. Because of these variables, it is critical in many Dl water applications to know the precise quality. Resistivity/ conductivity is the most convenient method for testing Dl water quality. Deionized pure water is a poor electrical conductor, having a resistivity of 18.2 million ohm-cm (18.2 megohm) and conductivity of 0.055 microsiemens. It is the amount of ionized substances (or salts) dissolved in the water which determines water’s ability to conduct electricity. Therefore, resistivity and its inverse, conductivity, are good general purpose quality parameters.

Because temperature dramatically affects the conductivity of water, conductivity measurements are internationally referenced to 25°C to allow for comparisons of different samples. With typical water supplies, temperature changes the conductivity an average of 2%/°C, which is relatively easy to compensate. Deionized water, however, is much more challenging to accurately measure since temperature effects can approach 10%/°C! Accurate automatic temperature compensation, therefore, is the “heart’ of any respectable instrument.

RECOMMENDED MYRON L METERSPortable instruments are typically used to measure Dl water quality at points of use, pinpoint problems in a Dl system confirm monitor readings, and test the feed water to the system. The handheld Myron L meters have been the first choice of Dl water professionals for many years. For two-bed Dl systems, there are several usable models with displays in either microsiemens or ppm (parts per million) of total dissolved solids. The most versatile instruments for Dl water is the 4P or 6PFCE Ultrameter II™, which can measure both ultrapure mixedbed quality water and unpurified water. It should be noted that once Dl water leaves the piping, its resistivity will drop because the water absorbs dissolved carbon dioxide from the air. Measuring of ultrapure water with a hand-held instrument requires not only the right instrument, but the right technique to obtain accurate, repeatable readings. Myron L meters offer the accuracy and precision necessary for ultrapure water measurements.

Inline Monitor/controllers are generally used in the more demanding Dl water applications. Increased accuracy is realized since the degrading effect of carbon dioxide on high purity water is avoided by use of an in-line sensor (cell). This same degradation of ultrapure water is the reason there are no resistivity calibration standard solutions (as with conductivity instruments). Electronic sensor substitutes are normally used to calibrate resistivity Monitor/controllers.

Myron L Meters carries a variety of inline instruments, including resistivity Monitor/controllers designed specifically for Dl water. Seven resistivity ranges are available to suit any Dl water application: 0-20 megohm, 0-10 megohm, 0-5 megohm, 0-2 megohm, 0-1 megohm, 0-500 kilohm, and 0-200 kilohm. Temperature compensation is automatic and achieved via a dual thermistor circuit. Monitor/controller models contain an internal adjustable set point, piezo alarm connectors and a heavy-duty 10 amp relay circuit which can be used to control an alarm, valves, pump, etc. Available options include 4-20 milliamp output, 3 sensor input, 3 range capability and temperature. Internal electronic sensor substitutes are standard on all Monitor/controllers.

Sensors are available constructed in either 316 stainless steel or titanium. All sensors are provided with a 3/4” MNPT polypropylene bushing and 10 ft./3 meters of cable. Optional PVDF or stainless steel bushings can be ordered, as well as longer cable lengths up to 100 ft./30 meters.

The following table briefly covers recommended Myron L meters for Dl water applications.

DEIONIZED WATER APP TABLE

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MyronLMeters.com is the premier internet retailer for all recommended Myron L meters above. Save 10% when you order online at MyronLMeters.com.

Categories : Uncategorized

DEIONIZED WATER APPLICATIONS: MyronLMeters.com

Posted by 11 Apr, 2014

TweetYears ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash. THE DEIONIZATION PROCESS The vast majority of dissolved […]

Years ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash.

THE DEIONIZATION PROCESS
The vast majority of dissolved impurities in modern water supplies are ions such as calcium, sodium, chlorides, etc. The deionization process removes ions from water via ion exchange. Positively charged ions (cations) and negatively charged ions (anions) are exchanged for hydrogen (H+) and hydroxyl (OH-) ions, respectively, due to the resin’s greater affinity for other ions. The ion exchange process occurs on the binding sites of the resin beads. Once depleted of exchange capacity, the resin bed is regenerated with concentrated acid and caustic which strips away accumulated ions through physical displacement, leaving hydrogen or hydroxyl ions in their place.

DEIONIZER TYPES
Deionizers exist in four basic forms: disposable cartridges, portable exchange tanks, automatic units, and continuous units. A two-bed system employs separate cation and anion resin beds. Mixed-bed deionizers utilize both resins in the same vessel. The highest quality water is produced by mixed-bed deionizers, while two-bed deionizers have a larger capacity. Continuous deionizers, mainly used in labs for polishing, do not require regeneration.

TESTING Dl WATER QUALITY
Water quality from deionizers varies with the type of resins used, feed water quality, flow, efficiency of regeneration, remaining capacity, etc. Because of these variables, it is critical in many Dl water applications to know the precise quality. Resistivity/ conductivity is the most convenient method for testing Dl water quality. Deionized pure water is a poor electrical conductor, having a resistivity of 18.2 million ohm-cm (18.2 megohm) and conductivity of 0.055 microsiemens. It is the amount of ionized substances (or salts) dissolved in the water which determines water’s ability to conduct electricity. Therefore, resistivity and its inverse, conductivity, are good general purpose quality parameters.

Because temperature dramatically affects the conductivity of water, conductivity measurements are internationally referenced to 25°C to allow for comparisons of different samples. With typical water supplies, temperature changes the conductivity an average of 2%/°C, which is relatively easy to compensate. Deionized water, however, is much more challenging to accurately measure since temperature effects can approach 10%/°C! Accurate automatic temperature compensation, therefore, is the “heart’ of any respectable instrument.

RECOMMENDED MYRON L METERS
Portable instruments are typically used to measure Dl water quality at points of use, pinpoint problems in a Dl system confirm monitor readings, and test the feed water to the system. The handheld Myron L meters have been the first choice of Dl water professionals for many years. For two-bed Dl systems, there are several usable models with displays in either microsiemens or ppm (parts per million) of total dissolved solids. The most versatile instruments for Dl water is the 4P or 6PFCE Ultrameter II™, which can measure both ultrapure mixedbed quality water and unpurified water. It should be noted that once Dl water leaves the piping, its resistivity will drop because the water absorbs dissolved carbon dioxide from the air. Measuring of ultrapure water with a hand-held instrument requires not only the right instrument, but the right technique to obtain accurate, repeatable readings. Myron L meters offer the accuracy and precision necessary for ultrapure water measurements.

Inline Monitor/controllers are generally used in the more demanding Dl water applications. Increased accuracy is realized since the degrading effect of carbon dioxide on high purity water is avoided by use of an in-line sensor (cell). This same degradation of ultrapure water is the reason there are no resistivity calibration standard solutions (as with conductivity instruments). Electronic sensor substitutes are normally used to calibrate resistivity Monitor/controllers.

Myron L Meters carries a variety of inline instruments, including resistivity Monitor/controllers designed specifically for Dl water. Seven resistivity ranges are available to suit any Dl water application: 0-20 megohm, 0-10 megohm, 0-5 megohm, 0-2 megohm, 0-1 megohm, 0-500 kilohm, and 0-200 kilohm. Temperature compensation is automatic and achieved via a dual thermistor circuit. Monitor/controller models contain an internal adjustable set point, piezo alarm connectors and a heavy-duty 10 amp relay circuit which can be used to control an alarm, valves, pump, etc. Available options include 4-20 milliamp output, 3 sensor input, 3 range capability and temperature. Internal electronic sensor substitutes are standard on all Monitor/controllers.

Sensors are available constructed in either 316 stainless steel or titanium. All sensors are provided with a 3/4″ MNPT polypropylene bushing and 10 ft./3 meters of cable. Optional PVDF or stainless steel bushings can be ordered, as well as longer cable lengths up to 100 ft./30 meters.

The following table briefly covers recommended Myron L meters for Dl water applications.

DEIONIZED WATER APP TABLE

Capture

 

MyronLMeters.com is the premier internet retailer for all recommended Myron L meters above. Save 10% when you order online at MyronLMeters.com.

Categories : Application Advice, Case Studies & Application Stories, Product Updates, Science and Industry Updates, Technical Tips

Ultrameter: Measuring Conductivity, TDS and Resistivity: MyronLMeters.com

Posted by 1 Mar, 2014

TweetPlease note:  These procedures apply to Ultrameters, Pool Pros, Tech Pros, and D-4 and D-6 dialysate meters. Measuring Conductivity & TDS 1. Rinse cell cup 3 times with sample to be measured. (This conditions the temperature compensation network and prepares the cell.) 2. Refill cell cup with sample. 3. Press COND or TDS. 4. Take […]

Please note:  These procedures apply to Ultrameters, Pool Pros, Tech Pros, and D-4 and D-6 dialysate meters.

Measuring Conductivity & TDS

1. Rinse cell cup 3 times with sample to be measured. (This conditions

the temperature compensation network and prepares the cell.)

2. Refill cell cup with sample.

3. Press COND or TDS.

4. Take reading. A display of [- - - -] indicates an over range condition.

Measuring Resistivity

Resistivity is for low conductivity solutions. In a cell cup the value may drift from trace contaminants or absorption from atmospheric gasses, so measuring a flowing sample is recommended.

1. Ensure pH protective cap is secure to avoid contamination.

2. Hold instrument at 30° angle (cup sloping downward).

3. Let sample flow continuously into conductivity cell with no aeration.

4. Press RES key; use best reading.

NOTE: If reading is lower than 10 kilohms display will be dashes: [ - - - - ]. Use Conductivity.

If you have further questions, please watch our Ultrameter 6P product overview video here: http://blog.myronlmeters.com/ultrameter-ii-product-review/

 IV. AFTER USING THE ULTRAMETER II

Maintenance of the Conductivity Cell

Rinse out the cell cup with clean water. Do not scrub the cell. For oily films, squirt in a foaming non-abrasive cleaner and rinse. Even if a very active chemical discolors the electrodes, this does not affect the accuracy; leave it alone.

Myron L Meters is the premier internet retailer of Myron L meters, solutions, parts and accessories. Save 10% on the Ultrameter II 6PFCe when you order online at MyronLMeters.com.

Categories : Application Advice, Technical Tips

Cleaning The Ultrameter II 6P Sensors: MyronLMeters.com

Posted by 1 Mar, 2014

TweetConductivity/TDS/Resistivity The conductivity cell cup should be kept as clean as possible. Flushing with clean water following use will prevent buildup on electrodes. However, if very dirty samples — particularly scaling types — are allowed to dry in the cell cup, a film will form. This film reduces accuracy. When there are visible films of […]

Conductivity/TDS/Resistivity

The conductivity cell cup should be kept as clean as possible. Flushing with clean water following use will prevent buildup on electrodes. However, if very dirty samples — particularly scaling types — are allowed to dry in the cell cup, a film will form. This film reduces accuracy. When there are visible films of oil, dirt, or scale in the cell cup or on the electrodes, use isopropyl alcohol or a foaming non-abrasive household cleaner. Rinse out the cleaner and your Ultrameter II is again ready to use.

pH/ORP (6PFCE)

The unique pH/ORP sensor in your Ultrameter II  is a nonrefillable combination type that features a porous liquid junction. It should not be allowed to dry out. To keep it from drying out and to prolong the life of the sensor, use SS sensor storage solution found here: http://www.myronlmeters.com/Myron-L-pH-ORP-Sensor-Storage-Solutions-32-oz-p/s-ssq.htm.  However, if this occurs, the sensor may sometimes be rejuvenated by first cleaning the sensor well with Isopropyl alcohol or a liquid spray cleaner such as Windex™ or Fantastic™ and rinsing well. Do not scrub or wipe the pH/ORP sensor.

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Then use one of the following methods:

1.            Pour a HOT salt solution ~60°C/140°F — a potassium chloride (KCI) solution such as Myron L pH/ORP Sensor Storage Solution is preferable, but HOT tap water with table salt (NaCl) will work fine — in the sensor well and allow to cool. Retest.

or

2.            Pour DI water in the sensor well and allow to stand for no more than 4 hours (longer can deplete the reference solution and damage the glass bulb). Retest. If neither method is successful, the sensor must be replaced.

“Drifting” can be caused by a film on the pH sensor bulb and/or reference. Use isopropyl alcohol (IPA) or spray a liquid cleaner such as Windex™ or Fantastic™ into the sensor well to clean it. The sensor bulb is very thin and delicate. Do not scrub or wipe the pH/ORP sensor. Leaving high pH (alkaline) solutions in contact with the pH sensor for long periods of time is harmful and will cause damage. Rinsing such liquids from the pH/ORP sensor well and refilling it with Myron L Storage Solution, a saturated KCl solution, pH 4 buffer, or a saturated solution of table salt and tap water, will extend the useful life.

Samples containing chlorine, sulfur, or ammonia can “poison” any pH electrode. If it is necessary to measure the pH of any such sample, thoroughly rinse the sensor well with clean water immediately after taking the measurement. Any sample element that reduces (adds an electron to) silver, such as cyanide, will attack the reference electrode.

Replacement sensors are available here:  http://www.myronlmeters.com/Myron-L-RPR-Ultrameter-pH-ORP-Sensor-p/a-rpr.htm

Myron L Meters is your best internet source for Ultrameter 6P parts and accessories.  You can always save 10% on Myron L meters when you order online at MyronLMeters.com.

 

Categories : Care and Maintenance, Technical Tips

The Ultrameter III 9PTKA: MyronLMeters.com

Posted by 12 Jun, 2013

Tweet Myron l Meters Ultrameter III 9PTKA from Myron L Meters

Myron l Meters Ultrameter III 9PTKA from Myron L Meters
Categories : Product Updates, Uncategorized

The Ultrameter II 6P: MyronLMeters.com

Posted by 12 Jun, 2013

Tweet Myron l Meters Ultrameter II 6p from Myron L Meters

Myron l Meters Ultrameter II 6p from Myron L Meters
Categories : Product Updates

The Ultrameter II 4P: MyronLMeters.com

Posted by 12 Jun, 2013

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Categories : Product Updates

Deionized water

Posted by 9 Aug, 2012

Tweet     Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes –   even the final rinse  at the local car wash. THE DEIONIZATION PROCESS Most dissolved impurities in modern water supplies are ions like calcium, sodium, chlorides, […]

 

 

Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes –   even the final rinse  at the local car wash.

THE DEIONIZATION PROCESS

Most dissolved impurities in modern water supplies are ions like calcium, sodium, chlorides, etc. The deionization process removes ions from water via ion exchange. Positively charged ions (cations) and negatively charged ions (anions) are exchanged for hydrogen (H+) and hydroxyl (OH-) ions,  respectively, due  to the  resin’s greater affinity for other ions. The ion exchange process occurs on the binding sites of the resin beads. Once depleted of exchange capacity, the resin bed is regenerated with concentrated acid and caustic which strips away accumulated ions through physical displacement, leaving hydrogen or hydroxyl ions in their place.

DEIONIZER TYPES

Deionizers exist in four basic forms: disposable cartridges, portable exchange tanks, automatic units, and continuous units. A two-bed system employs separate cation and anion resin beds. Mixed-bed deionizers utilize both resins in the same vessel. The highest quality water is produced by mixed-bed deionizers, while two-bed deionizers have a larger capacity. Continuous deionizers, mainly used in labs for polishing, do not require regeneration.

TESTING Dl WATER QUALITY

Water quality from deionizers varies with the type of resins used, feed  water  quality,  flow, efficiency  of regeneration, remaining capacity, etc. Because of these variables, it is critical in many Dl water applications to know the precise quality. Resistivity/ conductivity is the most convenient method for testing Dl water quality. Deionized pure water is a poor electrical conductor, having a resistivity of 18.2 million ohm-cm (18.2 megohm) and conductivity of 0.055 microsiemens. It is the amount of ionized substances (or salts) dissolved in the water which determines water’s ability to conduct electricity. Therefore, resistivity and its inverse, conductivity, are good general purpose quality parameters.

Because temperature dramatically affects the conductivity of water, conductivity measurements are internationally referenced to 25°C to allow for comparisons of different samples. With typical water supplies, temperature changes the conductivity an average of 2%/°C, which is relatively easy to compensate. Deionized water, however, is much more challenging to accurately measure since temperature effects can approach 10%/°C!  Accurate automatic temperature compensation, therefore, is the heart of any respectable instrument.

 RECOMMENDED INSTRUMENTATION

Portable instruments are typically used to measure Dl water quality at points of use, pinpoint problems in a Dl system confirm monitor readings, and test the feed water to the system. The handheld Myron L meters have been the  first choice of Dl water professionals for many years. For two-bed Dl systems, there are several usable models with displays in either microsiemens or ppm (parts per million) of total dissolved solids. The most versatile instruments for Dl water is the Ultrameter II 4P or Ultrameter II 6PFCE , which can measure both ultrapure mixed-bed quality water and unpurified water. It should be noted that once Dl water leaves the piping, its resistivity will drop because the water absorbs dissolved carbon dioxide from the air.  Measuring of ultrapure water with a hand-held instrument requires not only the right instrument, but the right technique to obtain accurate, repeatable readings. Myron L meters offer the accuracy and precision necessary for ultrapure water measurements.

In-line Monitor/controllers are generally used in the more demanding Dl water applications. Increased accuracy is realized since the degrading effect of carbon dioxide on high purity water is avoided by use of an in-line sensor (cell). This same degradation of ultrapure water is the reason there are no resistivity calibration standard solutions (as with conductivity instruments). Electronic sensor substitutes are normally used to calibrate resistivity Monitor/controllers.

Myron L Meters carries a variety of in-line instruments, including resistivity Monitor/controllers which are designed specifically for Dl water. Seven resistivity  ranges are  available to suit any Dl water application: 0-20 megohm, 0-10 megohm,

0-5 megohm,  0-2 megohm,  0-1 megohm,  0-500 kilohm, and 0-200 kilohm. Temperature compensation is automatic and achieved via a dual thermistor circuit. Monitor/controller models contain an internal adjustable set point, Piezo alarm connectors and a heavy-duty 10 amp relay circuit which can be used to control an alarm, valves, pump, etc. Available options include 4-20 milliamp output, 3 sensor input, 3 range capability and temperature.  Internal electronic sensor substitutes are standard on all Monitor/controllers.

 

Categories : Application Advice, Science and Industry Updates, Technical Tips