Ultrameter™ Operation Manual Model 6P MYRON L COMPANY 10 - 02 (WEB) EG
Instrument Illustration Reference Junction under Glass pH Bulb pH/ORP Sensor (Replaceable) ORP Electrode pH Glass Electrode Conductivity Cell (Built-in Electrodes) Temperature Sensor pH/ORP Sensor Protective Cap Preprogrammed variable conductivity/ TDS ratios USER mode for programming special temperature compensation factor and conductivity/TDS ratio LOBATT CAL MEMORY M K mS µS PPM PPT % / °C mV KCl NaCl 442 User RATIO BUFFER COND ORP RES pH TDS Units of Measurement Megohms - cm Ω Kilohms -
FEATURES and SPECIFICATIONS A. Features: Superior resolution 4 digit LCD displays full 9999 µS/ppm. Accuracy of ±1% of reading (not merely full scale). All electrodes are internal for maximum protection. Latest 4 electrode cell technology. Waterproof to 3 feet/1 meter. Autoranging conductivity/TDS/resistivity. Prompts for easy pH calibration. Memory saves 20 readings. Factory calibrations stored in microprocessor. 3 conductivity/TDS solution conversions preprogrammed into microprocessor.
TABLE OF CONTENTS VI. CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 A. Calibration Intervals . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 B. Rules for Calibration in the Ultrameter . . . . . . . . . . . . 14 1. Calibration Steps . . . . . . . . . . . . . . . . . . . . . . .14 2. Calibration Limits . . . . . . . . . . . . . . . . . . . . . . .15 C. Calibration Procedures . . . . . . . . . . . . . . . . . . . . . . . . 15 1.
XIV. TEMPERATURE COMPENSATION (Tempco) of Aqueous Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 A. Standardized to 25°C . . . . . . . . . . . . . . . . . . . . . . . . . .29 B. Tempco Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 C. An Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 D. A Chart of Comparative Error . . . . . . . . . . . . . . . . . . . .31 E. Other Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Operation of the Keys (See Instrument Illustration on page 1) 1. Measurement Keys in General Any of the 5 measurement keys in the upper part of the keypad turns on the instrument in the mode selected. The mode is shown at the bottom of the display, and the measurement units appear at the right. Pressing a measurement key does this even if you are in a calibration sequence and also serves to abandon a change (ref. Leaving Calibration, pg. 15). 2.
or at least a strong table salt solution. Not distilled water. (ref. pH and ORP Practices, pg. 24) 2. Rinse sensor well 3 times with sample to be measured. Shake out each sample to remove any residual liquid. IV. 3. Refill sensor well with sample. 4. Press 5. Take reading. 6. IMPORTANT : After use, fill pH/ORP sensor well with Myron L Storage Solution, a strong KCl solution or pH 4 buffer, and replace protective cap. Do not allow pH/ORP sensor to dry out.
conversion. Generally, using KCl for conductivity, NaCl for resistivity, and 442 (Natural Water characteristic) for TDS will reflect present industry practice for standardization. This is the setup as shipped from the factory (ref. Solution Characteristics, pg. 32). The USER selection allows a custom value to be entered for the temperature compensation of conductivity and also the conversion ratio if measuring TDS. Temperature Compensation, pg. 29). This feature does not apply to pH or ORP. a.
a. While in “USER” mode, press TDS . b. Press CAL MCLR Depending on what is being calibrated, there may be 1, 2 or 3 steps to the calibration procedures. twice (to skip over tempco adjustment), and KCl, NaCl or 442 “RATIO ” will appear (see Figure 4). c. Adjust with MS or MR keys until new conversion ratio is displayed. d.
b. Refill conductivity cell with same standard. c. Press press COND CAL MCLR µS 442 , “CAL” icon will appear on the display (see Fig. 5). d. CAL or TDS , then Press MS or MR °C COND Figure 5 4. Reloading Factory Calibration (Cond or TDS) If calibration is suspect or known to be wrong, and no standard solution is available, the calibration value can be replaced with the original factory value for that solution.
will be the uncalibrated sensor. annunciators will be lit (see Figures 7 and 8). CAL N O T E S : If a wrong buffer is added (outside of 6-8 pH),“7 ” and BUFFER ” will flash, and the Ultrameter will not adjust. The uncalibrated pH value displayed in step 4 will assist in determining the accuracy of the pH sensor. If the pH reading is above 8 with pH 7 buffer solution, the sensor well needs additional rinsing or the pH sensor is defective and needs to be replaced. CAL BUFFER BUFFER pH pH Figure 7 5.
for ORP are highly reactive and potentially hazardous, your Ultrameter has an electronic ORP calibration. This causes the zero point on the reference electrode to be set whenever pH 7 calibration is done. 7. Temperature Calibration Temperature calibration is not necessary in the Ultrameter. VII. MEMORY This feature allows up to 20 readings with their temperatures to be stored simultaneously for later recall. 1. A. Memory Storage While displaying a measurement, press displayed value.
X. Figure 11 Figure 12 CAL 4. Press MCLR ; the display will change to the other unit. 5. Press COND ; all temperature readings are now in degrees last shown. N O T E : Tempco will still be shown in %/°C. IX. TOTAL RETURN to FACTORY SETTINGS “FAC SEL” There may come a time when it would be desirable to quickly reset all the recorded calibration values in the instrument back to the factory settings.
fluid washes into the conductivity cell. D. pH and ORP Practices to Maintain Calibration. 1. Keep the sensor wet with Myron L Storage Solution. 2. Rinse away caustic solutions immediately after use. ORP calibration solutions are not only caustic, but 5% is considered very accurate. By using the pH zero setting (0 mV = 7 pH) for ORP and precision electronics for detection, the Ultrameter delivers better accuracy without calibration than a simpler instrument could using calibration solutions. XI.
Leaving high pH (alkaline) solutions in contact with the pH sensor for long periods of time can damage it. Rinsing such liquids from the pH/ORP sensor well and refilling well with Myron L Storage Solution, a saturated KCl solution, pH 4 buffer, or a salty tap water, will extend the sensor’s useful life. Samples containing chlorine, sulfur, or ammonia can "poison" any pH electrode.
XII. TROUBLESHOOTING CHART Symptom Possible Cause Corrective Action No display, even though measurement key pressed Battery weak or not connected. Check connections or replace battery (ref. Battery Replacement, pg. 24). Inaccurate pH readings 1. pH calibration needed (ref. pH Cal., pg. 17). 2. Cross-contamination from residual pH buffers or samples in sensor well. 3. Calibration with expired pH buffers. 1. Recalibrate instrument. 2. Thoroughly rinse sensor well. 3.
XIII. ACCESSORIES A. Conductivity/TDS Standard Solutions Your Ultrameter has been factory calibrated with the appropriate Myron L Company NIST traceable KCl, NaCl, and our own 442 standard solutions. Most Myron L conductivity standard solution bottles show three values referenced at 25°C: Conductivity in microsiemens/micromhos and the ppm/TDS equivalents based on our 442 Natural Water™ and NaCl standards. All standards are within ±1.0% of reference solutions. 1.
D. A Chart of Comparative Error: In the range of 1000 µS, the error using KCl on a solution that should be compensated as NaCl or as 442, is shown in the graph below. 2.500% 2.400% 7% 2.300% 442 error with KCl tempco 6% 2.200% NaCl error with KCl tempco 5% 2.100% % / °C 2.000% 4% 3% 1.900% 1.800% KCl % / °C 1.700% 2% 1% 1.600% Temperature 1.500% 0 5 10 15 20 25 30 35 40 45 50 55 60 Chart 1 0% (1)% Temperature (2)% C.
to indicate a certain setpoint or minimum concentration or trend. The Ultrameter gives the user the capability to take data in “KCl conductivity units” to compare to older published data, in terms of NaCl or 442, or as may be appropriate. The Ultrameter can be used to reconcile data taken with other compensation assumptions, especially with its ability to allow custom characteristics through the USER mode. XV.
Another solution would have a different tempco because of its ionization activity. And, that tempco may be a little different at a different concentration or temperature. This is why the Ultrameter uses mathematically generated models for known salt characteristics that 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.
Glass surface significant migration of liquids through the plug material. Figure 14 H+ ions 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 is damaged by drying out because insoluble crystals may form in a Electrode wire layer, obstructing contact with test solutions. See pH/ORP, pg. 25. KCl solution 4.
XVIII. GLOSSARY Anions - Negatively charged ions. See Solution Characteristics, pg. 32. Algorithm - A procedure for solving a mathematical problem. See Temperature Compensation and TDS Derivation, pg. 33. Logarithm - An arithmetic function. See pH Units, pg. 35. ORP Oxidation-Reduction Potential or REDOX, See ORP/ Oxidation-Reduction Potential/REDOX, pg. 37. - Reduce - As in ORP. TDS Total Dissolved Solids or the Total Conductive Ions in a solution. See Conductivity Conversion to TDS, pg. 32.
Ultrameter™ Operation Manual Addendum Models 4P & 6P Software Versions 2.03, 2.10, 2.51 & Later* * See page 5 to determine the version of software of your Ultrameter™.
I. ENHANCED HIGH RESISTIVITY MEASUREMENTS The resistivity calculations in the Ultrameter have been improved for measuring waters greater than 10 Megohms. When the Ultrameter is in one of the solution modes (i.e. KCl, NaCl or 442) and the resistivity reading is greater than 10 Megohms, the Ultrameter performs automatic temperature compensation for high purity water. As such, the maximum possible value that should be displayed for water is 18.2. It may be possible to display readings higher than 18.
II. USER MODE CALIBRATION LINK 4. A new function has been added to the Ultrameter that makes calibration of the unit while in "User" mode easier, and more repeatable and accurate than other calibration methods. It is recommended that this calibration method be used to provide the highest degree of confidence when the Ultrameter is used in "User" mode. Press the CAL MCLR key. The instrument will display "S E L " and the “User” Icon. Fig. 7. User Figure 7 A. 1. 2.
4. Press the MR key until "User" is the only solution icon being displayed. CAL 5. Press the 6. The User mode calibration "Link" has now been canceled. MCLR key. NOTES: 1. To maintain repeatability, use the same standard solutions for future calibrations. 2. Calibration of the Ultrameter Gain Factor for User mode is not available when the calibration link has been established. The other calibration functions (i.e. Temperature Compensation %/C settings and TDS Ratio settings) are still intact.
