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

Ultrapen PT4 Free Chlorine Pen Maintenance: MyronLMeters.com

Posted by 4 Apr, 2014

Tweet how to maintain and clean free chlorine sensor for the ultrapen pt4 Ultrapen PT4 Free Chlorine Pen MAINTENANCEI. Routine Maintenance1. ALWAYS rinse the FCE sensor with clean water after each use.2. ALWAYS replace the soaker cap half filled with Sensor Storage Solution to prevent thesensor from drying out after each use.3. Do not drop, […]

how to maintain and clean free chlorine sensor for the ultrapen pt4 how to maintain and clean free chlorine sensor for the ultrapen pt4

Ultrapen PT4 Free Chlorine Pen

MAINTENANCEI. Routine Maintenance1. ALWAYS rinse the FCE sensor with clean water after each use.2. ALWAYS replace the soaker cap half filled with Sensor Storage Solution to prevent thesensor from drying out after each use.3. Do not drop, throw, or otherwise strike the PT4. This voids the warranty.4. Do not store the PT4 in a location where the ambient temperatures exceed its specified Operating/Storage Temperature limits.

II. Battery Replacement The PT4 display has a battery indicator that depicts the liferemaining in the battery. When the indicator icon is at 3 bars, the battery is full. When the indicator icon falls to 1 bar, replace the battery with an N type battery.

Capture

 

 

 

 

 

1. In a clean/dry environment, unscrew the pen cap in a counter-clockwise motion.2. Slide the cap and battery housing out of the PT4.3. Remove the depleted battery out of its housing.4. Insert a new battery into the battery housing oriented with the negative end touching the spring.5. Align the groove along the battery housing with the guide bump inside the PT4case and slide the battery housing back in.6. Screw the PT4 cap back on in a clockwise direction. Do not over tighten.

III. Sensor Cleaning (additional sensor cleaning methods at www.myronl.com) Cleaning the sensor: The Myron L Company recommends cleaning your sensor every two weeks, however this depends on application and frequency of use. Indications of a dirty sensor are slower and/or erroneous readings.There are three critical components in your PT4 sensor; a very sensitive glass pH sensor bulb, a platinum ORP electrode, and a temperature sensor encapsulated in a small glass noid. Use extreme caution when cleaning your PT4 sensor.To clean your sensor, select one of the following methods:• Basic Cleaning: Using a solution made of dish soap mixed with water and a cotton swab, gently clean the inside of the sensor body and platinum electrode, rinse thoroughly with clean water, then recondition the sensor.• Cleaning the pH Sensor Bulb: If the sensor becomes dirty, clean the sensor surface with an isopropyl soaked cotton swab. Then rinse thoroughly with clean water.• Deep cleaning the platinum ORP electrode: Using the ORP electrode cleaning paper and water, gently clean the platinum electrode, rinse thoroughly then recondition the sensor.To recondition the sensor: Rinse the sensor thoroughly with clean water, then allow it to soak in Storage Solution for a minimum of 1 hour (for best results allow the sensor to soak in Storage Solution overnight).

IV. FCE Sensor ReplacementCAUTION: Only Remove/Replace the FCE sensor in a CLEAN and DRYenvironment!To remove the FCE sensor: Remove the soaker cap; make sure the PT4 (including the FCE sensor) is clean and dry.Loosen the battery tray (to allow pressure equalization).Then firmly grasp the FCE sensor body and slowly pull the FCE sensor out.To install a new FCE sensor: Line up the alignment tabs on the FCE sensor with the alignment slots on the PT4 unit. Gently push the FCE sensor into position, then close the battery cap.

You will need: RPT4  Replacement FCE Sensor (with instructions)

MyronLMeters.com is the premier internet retailer of the Ultrapen PT4 and other reliable Myron L meters. Save 10% on Myron L meters when you order online HERE.

Categories : Uncategorized

Ultrapen PT4 Free Chlorine Pen Maintenance: MyronLMeters.com

Posted by 4 Apr, 2014

TweetUltrapen PT4 Free Chlorine Pen MAINTENANCE I. Routine Maintenance 1. ALWAYS rinse the FCE sensor with clean water after each use. 2. ALWAYS replace the soaker cap half filled with Sensor Storage Solution to prevent the sensor from drying out after each use. 3. Do not drop, throw, or otherwise strike the PT4. This voids […]

how to maintain and clean free chlorine sensor for the ultrapen pt4

how to maintain and clean free chlorine sensor for the ultrapen pt4

Ultrapen PT4 Free Chlorine Pen

MAINTENANCE
I. Routine Maintenance
1. ALWAYS rinse the FCE sensor with clean water after each use.
2. ALWAYS replace the soaker cap half filled with Sensor Storage Solution to prevent the
sensor from drying out after each use.
3. Do not drop, throw, or otherwise strike the PT4. This voids the warranty.
4. Do not store the PT4 in a location where the ambient temperatures exceed its specified Operating/Storage Temperature limits.

II. Battery Replacement The PT4 display has a battery indicator that depicts the life
remaining in the battery. When the indicator icon is at 3 bars, the battery is full. When the indicator icon falls to 1 bar, replace the battery with an N type battery.

Capture

 

 

 

 

 

1. In a clean/dry environment, unscrew the pen cap in a counter-clockwise motion.
2. Slide the cap and battery housing out of the PT4.
3. Remove the depleted battery out of its housing.
4. Insert a new battery into the battery housing oriented with the negative end touching the spring.
5. Align the groove along the battery housing with the guide bump inside the PT4
case and slide the battery housing back in.
6. Screw the PT4 cap back on in a clockwise direction. Do not over tighten.

III. Sensor Cleaning (additional sensor cleaning methods at www.myronl.com) Cleaning the sensor: The Myron L Company recommends cleaning your sensor every two weeks, however this depends on application and frequency of use. Indications of a dirty sensor are slower and/or erroneous readings.
There are three critical components in your PT4 sensor; a very sensitive glass pH sensor bulb, a platinum ORP electrode, and a temperature sensor encapsulated in a small glass noid. Use extreme caution when cleaning your PT4 sensor.
To clean your sensor, select one of the following methods:
• Basic Cleaning: Using a solution made of dish soap mixed with water and a cotton swab, gently clean the inside of the sensor body and platinum electrode, rinse thoroughly with clean water, then recondition the sensor.
• Cleaning the pH Sensor Bulb: If the sensor becomes dirty, clean the sensor surface with an isopropyl soaked cotton swab. Then rinse thoroughly with clean water.
• Deep cleaning the platinum ORP electrode: Using the ORP electrode cleaning paper and water, gently clean the platinum electrode, rinse thoroughly then recondition the sensor.
To recondition the sensor: Rinse the sensor thoroughly with clean water, then allow it to soak in Storage Solution for a minimum of 1 hour (for best results allow the sensor to soak in Storage Solution overnight).

IV. FCE Sensor Replacement
CAUTION: Only Remove/Replace the FCE sensor in a CLEAN and DRY
environment!
To remove the FCE sensor: Remove the soaker cap; make sure the PT4 (including the FCE sensor) is clean and dry.
Loosen the battery tray (to allow pressure equalization).
Then firmly grasp the FCE sensor body and slowly pull the FCE sensor out.
To install a new FCE sensor: Line up the alignment tabs on the FCE sensor with the alignment slots on the PT4 unit. Gently push the FCE sensor into position, then close the battery cap.

You will need: RPT4  Replacement FCE Sensor (with instructions)

MyronLMeters.com is the premier internet retailer of the Ultrapen PT4 and other reliable Myron L meters. Save 10% on Myron L meters when you order online HERE.

Categories : Care and Maintenance, Product Updates, Technical Tips

Ultrapen PT4 Free Chlorine Pen Calibration: MyronLMeters.com

Posted by 4 Apr, 2014

TweetIV. Calibration of the Ultrapen PT4 Free Chlorine Pen The manufacturer recommends calibrating twice a month, depending on usage. However, you should check the calibration whenever measurements are not as expected. For greatest accuracy, you should perform a 3-point wet pH calibration, and wet ORP calibration with the ORP Standard Solution closest in value to […]

how to calibrate free chlorine for the ultrapen pt4

how to calibrate free chlorine for the ultrapen pt4

IV. Calibration of the Ultrapen PT4 Free Chlorine Pen

The manufacturer recommends calibrating twice a month, depending on usage.

However, you should check the calibration whenever measurements are not as expected. For greatest accuracy, you should perform a 3-point wet pH calibration, and wet ORP calibration with the ORP Standard Solution closest in value to the solution you will be testing.

NOTE: If the measurement is NOT within calibration limits for any reason, “Error” will display. Check to make sure you are using a proper Myron L Company pH Buffer or ORP Standard Solution. If the solution is correct, clean the sensor as described in Sensor Cleaning section on page 4 of the operations manual. Restart calibration.

NOTE: Small bubbles trapped in the sensor may give a false calibration. After calibration is completed, measure the pH Buffer or ORP Standard Solutions again in solution check mode “SOL ck” (see pages 3 and 4 of the operations manual) to verify correct calibration.

NOTE: If at any point during calibration, you do not submerge the sensor in solution before the flashing slows, allow the PT4 to power off and start over.
NOTE: You should always calibrate with pH 7 first.

A. Calibration preparation
For maximum accuracy, fill 2 clean containers with each pH Buffer and/or ORP Standard Solution. Arrange them in such a way that you can clearly remember which is the rinse solution and which is the calibration standard/buffer. If you don’t have enough standard/ buffer, you can use 1 container of each standard/buffer for calibration and 1 container of clean water for all rinsing. Always rinse the FCE sensor between standard/buffer solutions. Ensure the FCE sensor is clean and free of debris.

B. pH Calibration using pH 7, 4, and 10 Buffer Solutions.
NOTE: You should always calibrate with pH 7 first.
1. Thoroughly rinse the PT4 by submerging the sensor in pH 7 Buffer rinse solution and swirling it around.
2. Push and release the push button to turn the PT4 on.
3. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL”, “PAr SEL”, “SOL ck”, and “ESC”.
4. Release the button when “CAL” displays.
5. The display will alternate between “PUSHnHLD” and “CAL.
6. Push and hold the button, The display will alternate between “PH” and “ORP”.
7. Release the button when “PH” is displayed.
8. The display will indicate “CAL” and the LED will flash rapidly.
9. While the LED flashes rapidly, dip the PT4 in pH 7 Buffer Calibration Solution so that the sensor is completely submerged.
10. While the LED flashes slowly, the pH calibration point will display along with “CAL”.
Swirl the PT4 around to remove bubbles, keeping the sensor submerged.
11. If the pH 7 calibration is successful, the display will indicate “SAVEd”, then “PUSHCONT” will be displayed (“PUSHCONT” will NOT be displayed if only calibrated with pH 4 or 10).
12. Push and release to continue or let the unit time out to exit after a 1-point or 2-point calibration.
13. Repeat steps 9 through 12 with pH 4 and 10 Buffer Solutions. After the 3rd calibration point is successfully saved, the display will indicate “SAVEd” and power off.
14. Verify calibration by retesting the calibration solution in solution check mode “SOL ck”, see section V below.

C. ORP Calibration using 80mV Quinhydrone, 260mV Quinhydrone, or 470mV MLC Light’s ORP Standard Solution.
NOTE: The PT4 has automatic temperature compensation in ORP calibration mode (from 15ºC to 30ºC).
1. Follow pH calibration steps 1 through 6, using ORP Solutions.
2. Release the button when “ORP” is displayed.
3. The display will indicate “CAL” and the LED will flash rapidly.
4. While the LED flashes rapidly, dip the PT4 in ORP Standard Solution so that the
sensor is completely submerged.
5. While the LED flashes slowly, the ORP calibration point will display along with “CAL”.
Swirl the PT4 around to remove any air bubbles, keeping the sensor submerged.
6. If the ORP calibration is successful, the display will indicate “CAL SAVEd”, then time out.
7. Verify calibration by retesting the calibration solution in solution check mode.

V. SOLUTION CHECK
Solution check is provided to verify the proper calibration value was recorded when using pH Buffers and ORP Standard Solutions. To verify proper calibration, simply put the PT4 into solution check mode, select the mode to verify (pH or ORP), then dip the sensor into the pH Buffer or ORP Calibration Solution so that the sensor is completely submerged and swirl around to release any air bubbles, then verify displayed value matches the value on the bottle.

To perform Solution Check:
1. Push and release the push button to turn the PT4 on.
2. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL”, “PAr SEL”, “SOL ck”, and “ESC”.
3. Release the button when “SOL ck” displays.
4. The display will alternate between “PUSHnHLD” and “SOL ck”.
5. Push and hold the button, The display will alternate between “PH” and “ORP”.
6. Release the button when desired mode (pH or ORP) is displayed.
7. While the LED flashes rapidly, dip the PT4 in FRESH buffer/calibration solution so that the sensor is completely submerged and swirl the PT4 around to remove any air bubbles.
8. Verify value displayed is correct.
NOTE: To verify ORP calibration while in solution check mode, you must manually correct for temperature variations from 25ºC. See instructions that come with the ORP Standard Solutions for temperature chart.

VI. Factory Calibration
When pH Buffers are not available, the PT4 can be returned to factory default calibration using the FAC CAL function. This will erase any stored wet calibration.
NOTE: Default factory calibration resets the electronics only and does NOT take the condition of the sensor into consideration.
To return your PT4 to factory calibration:
1. Push and release the push button.
2. Push and hold the button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL”, “PAr SEL”, “SOL ck”, and “ESC”.
3. Release the button when “FAC CAL” displays. The display will alternate between “PUSHnHLD” and “FAC CAL”.
4. Push and hold the push button. “SAVEd FAC” displays indicating the pen has been reset to its factory calibration.

MyronLMeters.com is the premier internet retailer of the Ultrapen PT4 and other reliable Myron L meters. Save 10% on Myron L meters when you order online HERE.

Categories : Application Advice, Care and Maintenance, Product Updates, Technical Tips

Ultrapen PT4 Free Chlorine Pen Measurement: MyronLMeters.com

Posted by 4 Apr, 2014

TweetOPERATING INSTRUCTIONS Ultrapen PT4 Free Chlorine Pen NOTE: Selecting “ESC” from any menu immediately powers the PT4 off without saving changes. I. Temperature Unit Selection The PT4 allows you to select the type of units used for displaying temperature: ˚C (Degrees Celsius) or ˚F (Degrees Fahrenheit). To set the preference: 1. Push and release the push […]

how to measure free chlorine with the ultrapen pt4

how to measure free chlorine with the ultrapen pt4

OPERATING INSTRUCTIONS Ultrapen PT4 Free Chlorine Pen
NOTE: Selecting “ESC” from any menu immediately powers the PT4 off without saving changes.

I. Temperature Unit Selection
The PT4 allows you to select the type of units used for displaying temperature:
˚C (Degrees Celsius) or ˚F (Degrees Fahrenheit).
To set the preference:
1. Push and release the push button to turn the PT4 on.
2. Push and hold the button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL”, “PAr SEL”, “SOL ck”, and “ESC”.
3. Release the button while “ºCºF TEMP” is displayed. The display will alternate between “PUSHnHLD” and “ºCºF TEMP”.
4. Push and hold the button. The display will alternate between “˚C”, “˚F” and “ESC”.
Release the button when desired unit preference displays.
5. “SAVEd ºC” or “SAVEd ºF” will display; then the unit will power off.

II. FCE Mode Selection
The PT4 allows you to select the FCE measurement mode you prefer:
Hold Mode (default) — will display real-time readings until stable or 2 minutes, which ever
comes fi then display fi readings.
LIVE Mode — real-time readings are displayed continuously for up to 5 minutes, a push and release of the button will turn your PT4 off immediately.
To set the FCE measurement mode preference:
1. Push and release the push button to turn the PT4 on.
2. Push and hold the button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL”, “PAr SEL”, “SOL ck”, and “ESC”.
3. Release the button when “ModE SEL” is displayed. The display will alternate between “PUSHnHLD” and “ModE SEL”.
4. Push and hold the push button. The display will alternate between “Hold”, “LIVE” and “ESC”.
5. Release the button when desired mode displays.
6. “SAVEd” will display, then the PT4 will power off.

III. FCE Measurement
The following table explains what the LED Indicator Light signals indicate and gives the duration of each signal:

Capture

 

 

 

CAUTION: To measure solution at the extremes of the specified temperature or FCE range, allow the PT4 to equilibrate by submerging the sensor in the sample solution for 1 minute prior to taking a measurement.

NOTE: If you cannot dip the PT4 in the sample solution, pour the sample into a clean container. If you don’t have a container or need to test a vertical stream of solution, use the scoop to hold sample solution.
1. Rinse the pen 3 times in a sample of the solution.
2. Push and release the push button.
3. While the LED flashes rapidly, dip the PT4 in FRESH sample solution so that the sensor is completely submerged. If you do not submerge the sensor in solution before the flashing slows, allow the PT4 to power off and retake the reading.
4. While the LED flashes slowly, swirl the PT4 around to remove any air bubbles, keeping the sensor submerged.
a. In Hold mode when the LED turns on solid, remove the PT4 from solution. The display will alternate between the final FCE and temperature readings. Note the readings for your records.
b. In LIVE mode allow the PT4 to remain in solution while the LED flashes slowly. The display will alternate between live FCE and temperature readings. Note the readings for your records. LIVE measurement will time out after 5 minutes OR push and release the push button to turn the PT4 off at any time during LIVE measurement.

MyronLMeters.com is the premier internet retailer of the Ultrapen PT4 and other reliable Myron L meters. Save 10% on Myron L meters when you order online HERE.

Categories : Application Advice, Product Updates, Technical Tips

Ultrapen PT4 Free Chlorine Pen Features: MyronLMeters.com

Posted by 4 Apr, 2014

TweetThe Myron L ULTRAPEN™ PT4 Free Chlorine Pen is designed to be extremely accurate, fast, and simple to use in diverse water quality applications. Advanced features include automatic temperature compensation in calibration mode; highly stable microprocessor-based circuitry; user-intuitive design; and waterproof housing. A true one-handed instrument, the PT4 is easy to calibrate and easy to […]

The Myron L ULTRAPEN™ PT4 Free Chlorine Pen is designed to be extremely accurate, fast, and simple to use in diverse water quality applications. Advanced features include automatic temperature compensation in calibration mode; highly stable microprocessor-based circuitry; user-intuitive design; and waterproof housing. A true one-handed instrument, the PT4 is easy to calibrate and easy to use. To take a measurement, you simply push a button then dip the PT4 in solution. Results display in seconds.

Capture

FEATURES
1. Push Button — turns PT4 on; selects mode and unit preferences.
2. Battery Cap — provides access to battery for replacement.
3. pocket Clip — holds PT4 to shirt pocket for secure storage.
4. Battery Indicator — indicates life remaining in battery.
5. Display — displays measurements, menu options, battery indicator, and firmware revision
(during power-up).
6. LED Indicator Light — indicates when to dip PT4 in solution, when measurement is in progress, and when to remove PT4 from solution.
7. FCE Sensor — measures Free Chlorine Equivalent of a solution.
8. Soaker Cap — contains Sensor Storage Solution to maintain sensor hydration. To remove, twist the soaker cap while pulling off using caution not to spill the Storage Solution. To replace, fill the soaker cap half full with Storage Solution. Twist the soaker cap while pushing back on, using caution, as excess Storage Solution may squirt out.
CAUTION: Do NOT push the soaker cap beyond the Cap Stop as sensor damage WILL
occur.
NOTE: The formation of KCl crystals around the soaker cap is normal. These crystals do not affect the sensor life, performance, or accuracy provided they are rinsed off with water prior to a test.
9. Scoop — used to hold sample solution when dipping is not possible. To install, push the scoop onto the sensor while shifting side-to-s
scoop off while shifting side-to-side. Verify the fully inserted into the PT4. If not, reinstall per FCE Sensor Replacement section on page 5. To use, hold the scoop directly under a vertical stream during measurement, avoiding bubbles.
10. Holster — run your belt through the strap in the back of the holster for hands-free portability.
11. Lanyard — attach through hole in top of pocket clip.
12. ORP Electrode Cleaning paper — for deep cleaning the platinum electrode.

Specifications
Free Chlorine: 0.00 – 10.00ppm
Free Chlorine Accuracy: < 5.00ppm ±0.3ppm, ≥ 5.00ppm ±0.5ppm
Free Chlorine Resolution: 0.01 ppm
Temperature Range: 0 – 71° C / 32 – 160° F
Temperature Accuracy: ± 0.1 ºC / ± 0.1 ºF
Temperature Resolution: 0.1ºC/0.1ºF
Time to Reading Stabilization: 10 – 45 seconds
Power Consumption: Active Mode 37 mA, Sleep Mode 2 μA
Temperature Compensation: Automatic In Calibration Mode From 15ºC to 30ºC
Physical Dimensions: 17.15 cm L x 1.59 cm D or 6.75 in. L x .625 in. D
Weight: 50.4 g / 1.78 oz. (without soaker cap and lanyard)
Case Material: Anodized Aircraft Aluminum with Protective Coating
Battery: One N type, Alkaline, 1.5V
Operating/Storage Temperature: 0 – 55ºC or 32 – 131ºF
Calibration Standard Solutions: pH4, pH7, pH10, ORP80, ORP260, ORP470
Enclosure Ratings: IP67 and NEMA6
EN61236-1: 2006 – Annex A: 2008: Electrostatic discharge to the PT4 may cause it to spontaneously turn on. If this occurs, the PT4 will turn off.

MyronLMeters.com is the premier internet retailer of the Ultrapen PT4 and other reliable Myron L meters. Save 10% on Myron L meters when you order online HERE.

Categories : Product Updates, Technical Tips

Conductivity Conversion to TDS in the Ultrameter: MyronLMeters.com

Posted by 1 Mar, 2014

TweetElectrical conductivity indicates solution concentration and ionization of the dissolved material. Since temperature greatly affects ionization, conductivity measurements are temperature dependent and are normally corrected to read what they would be at 25°C. A.           How It’s Done Once the effect of temperature is removed, the compensated conductivity is a function of the concentration (TDS). Temperature […]

Electrical conductivity indicates solution concentration and ionization of the dissolved material. Since temperature greatly affects ionization, conductivity measurements are temperature dependent and are normally corrected to read what they would be at 25°C.

A.           How It’s Done

Once the effect of temperature is removed, the compensated conductivity is a function of the concentration (TDS). Temperature compensation of the conductivity of a solution is performed automatically by the internal processor with data derived from chemical tables. Any dissolved salt at a known temperature has a known ratio of conductivity to concentration. Tables of conversion ratios referenced to 25°C have been published by chemists for decades.

B.           Solution Characteristics

Real world applications have to measure a wide range of materials and mixtures of electrolyte solutions. To address this problem, industrial users commonly use the characteristics of a standard material as a model for their solution, such as KCl, which is favored by chemists for its stability.

Users dealing with sea water, etc., use NaCl as the model for their concentration calculations. Users dealing with freshwater work with mixtures including sulfates, carbonates and chlorides, the three predominant components (anions) in freshwater that Myron L calls “Natural Water”. These are modeled in a mixture called “442™” which Myron L uses as a calibration standard, as it does standard KCl and NaCl solutions.

The Ultrameter II contains algorithms for these 3 most commonly referenced compounds. The solution type in use is displayed on the left. Besides KCl, NaCl, and 442, there is the User choice. The benefit of the User solution type is that one may enter the temperature compensation and TDS ratio by hand, greatly increasing accuracy of readings for a specific solution. That value remains a constant for all measurements and should be reset for different dilutions or temperatures.

C.           When does it make a lot of difference?

First, the accuracy of temperature compensation to 25°C determines the accuracy of any TDS conversion. Assume we have industrial process water to be pretreated by RO. Assume it is 45°C and reads 1500 µS uncompensated.

1.         If NaCl compensation is used, an instrument would report 1035 µS compensated, which corresponds to 510 ppm NaCl.

2.         If 442 compensation is used, an instrument would report 1024 µS compensated, which corresponds to 713 ppm 442.

The difference in values is 40%.

In spite of such large error, some users will continue to take data in the NaCl mode because their previous data gathering and process monitoring was done with an older NaCl referenced device.

Selecting the correct Solution Type on the Ultrameter II will allow the user to attain true TDS readings that correspond to evaporated weight.

If none of the 3 standard solutions apply, the User mode must be used.

TEMPERATURE COMPENSATION (Tempco) and TDS DERIVATION

The Ultrameter II contains internal algorithms for characteristics of the 3 most commonly referenced compounds. The solution type in use is displayed on the left. Besides KCl, NaCl, and 442, there is the User choice. The benefit of User mode is that one may enter the tempco and TDS conversion values of a unique solution via the keypad.

A. Conductivity Characteristics
When taking conductivity measurements, the Solution Selection determines the characteristic assumed as the instrument reports what a measured conductivity would be if it were at 25°C. The characteristic is represented by the tempco, expressed in %/°C. If a solution of 100 µS at 25°C increases to 122 µS at 35°C, then a 22% increase has occurred over this change of 10°C. The solution is then said to have a tempco of 2.2 %/°C. Tempco always varies among solutions because it is dependent on their individual ionization activity, temperature and concentration. This is why the Ultrameter II features mathematically generated models for known salt characteristics that also vary with concentration and temperature.

B. Finding the Tempco of an Unknown Solution

One may need to measure compensated conductivity of some solution unlike any of the 3 standard salts. In order to enter a custom fixed tempco for a limited measurement range, enter a specific value through the User function. The tempco can be determined by 2 different methods:

1. Heat or cool a sample of the solution to 25°C, and measure its conductivity. Heat or cool the solution to a typical temperature where it is normally measured. After selecting User function, set the tempco to 0 %/°C as in Disabling Temperature Compensation, pg. 15 (No compensation). Measure the new conductivity and the new temperature. Divide the % decrease or increase by the 25°C value. Divide that difference by the temperature difference.

2. Heat or cool a sample of the solution to 25°C, and measure its conductivity. Change the temperature to a typical measuring temperature. Set the tempco to an expected value as in User Programmable Temperature Compensation, pg. 15. See if the compensated value is the same as the 25°C value. If not, raise or lower the tempco and measure again until the 25°C value is read.

C. Finding the TDS Ratio of an Unknown Solution

Once the effect of temperature is removed, the compensated conductivity is a function of the concentration (TDS).

There is a ratio of TDS to compensated conductivity for any solution, which varies with concentration. The ratio is set during calibration in User mode as in User Programmable Conductivity to TDS Ratio, pg. 16.
A truly unknown solution has to have its TDS determined by evaporation and weighing. Then the solution whose TDS is now known can be measured for conductivity and the ratio calculated. Next time the same solution is to be measured, the ratio is known.

ph and ORP (6PFCE)

1. pH as an Indicator (6PFCE)

pH is the measurement of Acidity or Alkalinity of an aqueous solution. It is also stated as the Hydrogen Ion activity of a solution. pH measures the effective, not the total, acidity of a solution.
A 4% solution of acetic acid (pH 4, vinegar) can be quite palatable, but a 4% solution of sulfuric acid (pH 0) is a violent poison. pH provides the needed quantitative information by expressing the degree of activity of an acid or base. In a solution of one known component, pH will indicate concentration indirectly. However, very dilute solutions may be very slow reading, just because the very few ions take time to accumulate.

2. pH Units (6PFCE)

The acidity or alkalinity of a solution is a measurement of the relative availabilities of hydrogen (H+) and hydroxide (OH-) ions. An increase in (H+) ions increases acidity, while an increase in (OH-) ions increases alkalinity. The total concentration of ions is fixed as a characteristic of water, and balance would be 10-7 mol/liter (H+) and (OH-) ions in a neutral solution (where pH sensors give 0 voltage).
pH is defined as the negative logarithm of hydrogen ion concentration. Where (H+) concentration falls below 10-7, solutions are less acidic than neutral, and therefore are alkaline. A concentration of 10-9 mol/liter of (H+) would have 100 times less (H+) ions than (OH-) ions and be called an alkaline solution of pH 9.

3. The pH Sensor (6PFCE)

The active part of the pH sensor is a thin glass surface that is selectively receptive to hydrogen ions. Available hydrogen ions in a solution will accumulate on this surface and a charge will build up across the glass interface. The voltage can be measured with a very high impedance voltmeter circuit; the dilemma is how to connect the voltmeter to solution on each side.
The glass surface encloses a captured solution of potassium chloride holding an electrode of silver wire coated with silver chloride. This is the most inert connection possible from a metal to an electrolyte. It can
still produce an offset voltage, but using the same materials to connect to the solution on the other side of the membrane causes the 2 equal offsets to cancel.
The problem is, on the other side of the membrane is an unknown test solution, not potassium chloride. The outside electrode, also called the Reference Junction, is of the same construction with a porous plug in place of a glass barrier to allow the junction fluid to contact the test solution without significant migration of liquids through the plug material. Figure 33 shows a typical 2 component pair. Migration does occur, and this limits the lifetime of a pH junction from depletion of solution inside the reference junction or from contamination. The junction may be damaged if dried out because insoluble crystals may form in a layer, obstructing contact with test solutions.

Capture

Figure 33

 

Glass Surface

H+ ions

Junction plug
Platinum button

 

KCl solution

 

 

Glass

 

 

Electrode wires

 

 

 

4. The Myron L Integral pH Sensor (6PFCE)

The sensor in the Ultrameter II (see Figure 34) is a single construction in an easily replaceable package. The sensor body holds an oversize solution supply for long life. The reference junction “wick” is porous to provide a very stable, low permeable interface, and is located under the glass pH sensing electrode. This construction combines all the best features of any pH sensor known.

5. Sources of Error (6PFCE)

The most common sensor problem will be a clogged junction because a sensor was allowed to dry out. The symptom is a drift in the “zero” setting at 7 pH. This is why the Ultrameter II 6PFCE does not allow more than 1 pH unit of offset during calibration. At that point the junction is unreliable.

b. Sensitivity Problems

Sensitivity is the receptiveness of the glass surface. A film on the surface can diminish sensitivity and cause a long response time.

c. Temperature Compensation

pH sensor glass changes its sensitivity slightly with temperature, so the further from pH 7 one is, the more effect will be seen. A pH of 11 at 40°C would be off by 0.2 units. The Ultrameter II 6PFCE senses the sensor well temperature and compensates the reading.

B. ORP/Oxidation-Reduction Potential/REDOX (6PFCE)

1. ORP as an Indicator (6PFCE)

ORP is the measurement of the ratio of oxidizing activity to reducing activity in a solution. It is the potential of a solution to give up electrons (oxidize other things) or gain electrons (reduce).
Like acidity and alkalinity, the increase of one is at the expense of the other, so a single voltage is called the Oxidation-Reduction Potential, with a positive voltage showing, a solution wants to steal electrons (oxidizing agent). For instance, chlorinated water will show a positive ORP value.

2. ORP Units (6PFCE)

ORP is measured in millivolts, with no correction for solution temperature. Like pH, it is not a measurement of concentration directly, but of activity level. In a solution of only one active component, ORP indicates concentration. Also, as with pH, a very dilute solution will take time to accumulate a readable charge.

3. The ORP Sensor (6PFCE)
An ORP sensor uses a small platinum surface to accumulate charge without reacting chemically. That charge is measured relative to the solution, so the solution “ground” voltage comes from a reference junction – same as the pH sensor uses.

4. The Myron L ORP Sensor (6PFCE)

Figure 34, pg. 45, shows the platinum button in a glass sleeve. The same reference is used for both the pH and the ORP sensors. Both pH and ORP will indicate 0 for a neutral solution. Calibration at zero compensates for error in the reference junction. A zero calibration solution for ORP is not practical, so the Ultrameter II 6PFCE uses the offset value determined during calibration to 7 in pH calibration (pH 7 = 0 mV). Sensitivity of the ORP surface is fixed, so there is no gain adjustment either.

5. Sources of Error (6PFCE)

The basics are presented in pH and ORP, pg. 44, because sources of error are much the same as for pH. The junction side is the same, and though the platinum surface will not break like the glass pH surface, its protective glass sleeve can be broken. A surface film will slow the response time and diminish sensitivity. It can be cleaned off with detergent or acid, as with the pH glass.

C. Free Chlorine

1. Free Chlorine as an Indicator of Sanitizing Strength Chlorine, which kills bacteria by way of its power as an oxidizing agent, is the most popular germicide used in water treatment. Chlorine is not only used as a primary disinfectant, but also to establish a sufficient residual level of Free Available Chlorine (FAC) for ongoing disinfection.

FAC is the chlorine that remains after a certain amount is consumed by killing bacteria or reacting with other organic (ammonia, fecal matter) or inorganic (metals, dissolved CO2, Carbonates, etc) chemicals in solution. Measuring the amount of residual free chlorine in treated water is a well accepted method for determining its effectiveness in microbial control.

The Myron L  FCE method for measuring residual disinfecting power is based on ORP, the specific chemical attribute of chlorine (and other oxidizing germicides) that kills bacteria and microbes.

2. FCE Free Chlorine Units

The 6PIIFCE is the first handheld device to detect free chlorine directly, by measuring ORP. The ORP value is converted to a concentration reading (ppm) using a conversion table developed by Myron L Company through a series of experiments that precisely controlled chlorine levels and excluded interferants.

Other test methods typically rely on the user visually or digitally interpreting a color change resulting from an added reagent-dye. The reagent used radically alters the sample’s pH and converts the various chlorine species present into a single, easily measured species. This ignores the effect of changing pH on free chlorine effectiveness and disregards the fact that some chlorine species are better or worse sanitizers than others.

The Myron L 6PIIFCE avoids these pitfalls. The chemistry of the test sample is left unchanged from the source water. It accounts for the effect of pH on chlorine effectiveness by including pH in its calculation. For these reasons, the Ultrameter II’s FCE feature provides the best reading-to-reading picture of the rise and fall in sanitizing effectivity of free available chlorine.

The 6PIIFCE also avoids a common undesirable characteristic of other ORP-based methods by including a unique Predictive ORP value in its FCE calculation. This feature, based on a proprietary model for ORP sensor behavior, calculates a final stabilized ORP value in 1 to 2 minutes rather than the 10 to 15 minutes or more that is typically required for an ORP measurement.

The Myron L Ultrameter II 6PFCe is available at MyronLMeters.com, the premier internet retailer of Myron L products. Save 10% on the Myron L Ultrameter II6 PFCe when you order online here: http://www.myronlmeters.com/Myron-L-6P-Ultrameter-II-Multiparameter-Meter-p/dh-umii-6pii.htm

 

Categories : Application Advice, Technical Tips