- What is pH..?
The concentration of hydrogen ions is commonly expressed in terms of the pH scale. Low pH corresponds to high hydrogen ion concentration and vice versa. A substance that when added to water increases the concentration of hydrogen ions (while lowering the pH) is called an acid. A substance that reduces the concentration of hydrogen ions (while raising the pH), is called a base.
- What is a pH buffer..?
Some substances enable solutions to resist pH changes when an acid or base is added. Such substances are called buffers. Buffers are very important in helping organisms maintain a relatively constant pH.
- How does a Ph Monitor work..?
A Ph Monitor is designed to give a continuous readout of the solution pH value. Milwaukee Instruments has 3 different types of pH monitors, and some have user set point alarms. You can find all our monitors under the applications heading.
- How does a Ph Controller work..?
A pH Controller is designed to give a continuous readout of the solution, and has a user set point which allows the controller to turn power on and off to an attached device. Milwaukee Instruments offers 2 controllers.
- If I order a pH meter, what accessories do I need to use with it..?
Your Milwaukee Instruments meter will come with everything you need to get started. You should consider ordering at least two pH buffers, one at pH 7 and the other at either pH 4 or 10, as well as storage solution to prolong the life of your probe.
- Can I measure the pH of a gas..?
The only way to measure the pH of a gas is to dissolve it into distilled water and measure the mixture. Technically, the pH of the distilled water/gas mixture will be that of the gas.
- Is Automatic Temperature Compensation (ATC) really necessary..?
The necessity of ATC depends upon the required accuracy of a pH reading, because pH readings vary with temperature. For example a sample with a pH of 7 at 25 degrees Celsius may have a pH of 7.08 at 5 degrees Celsius, and a pH of 6.98 at 60 degrees Celsius. Many of our units come with ATC.
- Why does my SMS122 only come with 7.01 calibration solution..?
Because the SMS122 is used primarily in an aquarium environment, with both fresh and salt water aquariums operation is in the pH neutral zone which is 5.5 to 8.5. We strongly recommend that your unit be calibrated at the pH 7.0 position only, so we have included a starter pack of pH calibration solution 7.01.
- Why does my new pH probe have some type of salt around the cap..?
Salt build up around the probe when it is new is from probe protective shipping solution, and it is normal to see crusting around the protective cap. Rinse the salt off and let the probe soak for an hour in 4.01 calibration solution, storage solution or bottled water, then follow the calibration procedure instructions.
- How does one take soil pH measurements..?
Use a soil to water ratio, of 2 parts soil and 1 part bottled drinking water. Pack soil in cup, and always use a flat bottom measuring cup to assure proper proportions, then add the water. Stir or shake the soil and water mixture vigorously, then let sit for 1 to 2 minutes. Turn on your pH meter and be sure you have calibrated your meter before running the test, remove the cap to expose the sensor, and dip the sensor completely in the solution. Move the probe in the mix to be assured of good water to probe contact, and record the reading displayed on the meter.
- Why is a double junction electrode better than a single junction electrode..?
A double junction electrode is less likely to become clogged because the second junction is located higher up in the probe out of contact with the fluid.
- What pH calibration solution should I use..?
All manufacturers of meters and testers recommend that you use their specific calibration solution. Most meter and tester manufacturers use high quality calibration solution mix and quality control for their own meters, so always use our 7.01 or 4.01 for your Milwaukee Unit.
- Why is my pH reading jumping all over the place..?
If you're using your pH controller or moniter in either an electrolytic or saline environment, such as aquatic or hydroponic uses, try removing your pH probe and place it into a cup of the same solution you're trying to measure. If the numbers stop jumping around, then its likely that you have stray voltage in your system that is being picked up by the pH probe. Once you have isolated the source of this voltage and corrected it, your readings should be fine.
- What is the expected pH probe life..?
All Milwaukee Instruments probes are warranted for six months, and should last from 18 to 24 months if the probe is clean and kept wet in the proper storage solution.
- How do I test my pH probe to see if it needs replacing..?
A simple test can be performed using Windex glass cleaner with ammonia, and any type of soft drink. The procedure is as follows; turn your meter or tester on and place the probe in a soft drink, which is acidic, and the reading will be from 2.7 to 3.9. Then go to the Windex with ammonia which is alkaline. Your display should move very quickly up the scale to a point above 10.0. If the probe slowly moves up the scale, then it is time to consider replacing it.
- How do I clean my pH probe..?
You should use MA9016 cleaning solution for cleaning your probe, and MA9015 for storage of the probe when not in use.
- What is the difference between Single Point and Slope calibration..?
Single point is almost always done at the 7.0 position. Single point is fine as long as the area you are testing is within the neutral zone of 5.5 to 8.5. However, for accuracy in most applications, you need to have two point calibration. That is why most Milwaukee Instruments come with a 2 point calibration procedure, and most of our units are provided with both 7.01 and 4.01 calibration solution.
- How often should I do pH Calibration..?
To be the most accurate, you should calibrate before each use or set of uses. However, most units will hold calibration very well. If you are using your unit everyday, then check it once each day. If you get a reading that is above or below what you were expecting, then check the calibration at that point and retest your solution. You can find a Calibration and Probe reference chart on the Tech Tips page of this web site.
- How should I store my pH probe..?
You should use MA9016 cleaning solution for cleaning your probe, and MA9015 for storage of the probe when not in use. All pH probes use a cloth junction in the construction of the probe. This cloth is part of the diagnostic process in reading the pH. Never let the probe dry out. If the cloth becomes dry, the unit will not be able to read.
- Can I reuse my pH calibration solution..?
No, evaporation and contamination quickly change the mix.
- What are the symptoms of weak batteries..?
For the end user to be assured that the readings are accurate and not worry about battery strength, all Milwaukee Instruments units are designed to shut down when the batteries become too weak to give an accurate reading.
- During the calibration procedure, why does my PH52 or PH53 display keep blinking..?
During calibration, the 7.01 display number will keep blinking but the pH icon in the upper right corner will stop. When the pH icon stops blinking, press set, and the display will roll to 4.01 and start blinking. Wait for the pH icon in the upper right corner to once again stop blinking, then press set and turn your unit off. You are now calibrated. If the pH icon will not stop blinking during the calibration procedure described, then you need to soak the probe for a longer period. Remember, the PH 52 and PH 53 are waterproof an,d take several hours to condition before calibration.