NIST thermometer calibration: Temperature is a critical measurement for ensuring the safety and quality of many food products. Various metals can become brittle if not heated just right and to the proper temperature. (Graduation Day: Calibration of a Thermometer. Water Bath Procedure: Place certified calibrated thermometer and thermometer to be calibrated in a water bath. By doing the calibration lab, we can now calibrate a balance. 1.3 Experiment 1a - Procedure and Results Firstly two lengths of nickel chromium (Ni-Cr) wire and 1 length of pure nickel (Ni) wire, each measuring 30cm were cut from spools of the respective wires using a wire cutter. Undistilled water may contain many different minerals in varying concentrations, which would affect the results of our experiment. Graduation Day: How to Calibrate a Thermometer, Graduation Day: Thermometer Calibration Lab Photos. ( Log Out /  Record the results, using actual values, on the thermometer calibration log, along with the date and initials of the person performing the calibration procedure. Then place the thermometer with the plastic card in the water. Remove the thermometer and check for the temperature on the display. Gently submerge the thermometer on the plastic strip 2 inches into the iced beaker. Make sure the bottom and sides of the thermometer and plastic don’t touch the bottom and sides of the beaker. Fill a glass with ice and then fill it with cold tap water. This beaker of boiling water will help determine the 100˚C calibration on our thermometer. The thermometer we used in this lab, as well as the most common types of lab, indicate the temperature of certain things through the expansion of a liquid, usually alcohol or mercury. If you choose to calibrate your thermometer in increments of 5, divide the total distance by 5 instead. Since we knew at what temperature water boils and when it freezes we could find the temperatures in between by dividing by certain increments that we thought were acceptable for our thermometer. Request A Quote Learn More Micro Precision’s accredited in-lab and onsite calibration services for a wide range of RF Test Equipment. Alcohol thermometers have low accuracy for 2 main reasons. Take a beaker with 250 ml of distilled water. Just like watches can run slow or fast, food thermometers are subject to... 2. …and calibration of laboratory instruments and routinely used thermometers. Stir the ice water and let it sit for 2 minutes. -Rectangular piece of plastic (2 inches wide, 11 inches long). We have always had our lab set at 70 just to maintain a 71 DegF temp. Place the tip of the thermometer under the armpit. Although my lab partner and I tried our hardest to complete this experiment flawlessly, there were are few errors that could have possibly contributed to decreasing the accuracy of our thermometer. The smaller the increments, the more accurate your estimates of temperature will be. Locate 2 beaker that your chemistry teacher has set up in your classroom. We are also discovering what is necessary for scientific instruments to measure accurately. Placed the beaker onto hot plate to allow water to get to melting point. Temperature plays an important role within many industries and the processes they use on a day-to-day basis. Carefully take the thermometer out of the water and mark the top of the red fluid on the plastic strip with a black sharpie. These three errors contributed to much of the discrepancies. As a chemistry student, it is important to know the purpose of a thermometer and how it works. Set ruler and thermometer aside, and use beaker tongs to grab the beaker with hot water on the hot plate. Thermistors can be approximated by assuming a third-order function called the Steinhart-Hart approximation [ source on thermistor calibration ]: where T is the temperature calculated from the thermistor change in resistance, R . This may have affected the measurement we took for 0˚C because the thermometer may have already started adjusting back to room temperature by the time we had taken it out of the beaker and had found the sharpie. Heat bath to desired range. The number obtained tells you the difference in cm for every 5°C. To find the increments of measurements in between your two main calibrations, obtain a ruler and measure the distance between your 0˚C and 100˚C measurements. By now, the water on the hot plate should be a rolling boil. Meanwhile, write next to the bottom line 0°C and next to the second line 100°C. When touching the bottom of the hot plate with the thermometer will change the temperature because the bottom is hotter than the actual water. This will allow you to test the accuracy of your calibrated thermometer. Related Products: Water Thermometer. 5.1.3 Put the beaker in an oil bath fitted with a stirrer. thermometers) need only be identified with their unique identification number for traceability to their associated records. Make sure the bottom of the thermometer (the red glass bulb) lines up with the bottom of the plastic. Our finished scale went up by increments of 5. Some values in the table should have an associated unit, please make sure to note that unit in your table. While you wait for the water to start boiling, to save time, place ice in your other beaker. Many thermometers have a nut under their temperature dial that allows them to... 3. Remove thermometer from water and dry it off. Calibration is the act of comparing a device under test (DUT) of an unknown value with a reference standard of a known value. This is the 10°C line. Change ), You are commenting using your Twitter account. Ice water method for thermometer calibration The Ice-Water Method: An easy way to calibrate your thermometer is to put it in ice water and adjusting it to read. Applied Technical Services (ATS) regularly performs thermometer calibration services. You first determine the measurement deviation of the infrared thermometer from the correct temperature. Turn the heat on to high level. The purpose of this lab was to calibrate a thermometer by using the boiling and freezing point of water. The built-in precision reference sensor works as an accurate temperature reference. My partner and I also could have been more accurate when adding our own increments of 10. Micro Precision’s accredited thermodynamic & chemical calibration lab services with temperature, humidity, life science, and pharma capabilities. (e.g. Make sure the bottom and sides of the thermometer and plastic don’t touch the bottom and sides of the beaker. Alcohol also tends to wet the sides of the stem’s bore, which causes part of the liquid to remain along the sides of the bore when the temperature drops. The purpose of a thermometer is to indicate the temperature of various materials, whether the temperature in a certain place (the classroom for example), or the temperature of a substance, the temperature of water, the temperature of the oven, the temperature of our body (so that we know whether we are sick or not), etc. Patience is crucial when collecting accurate data, especially when using that data to create a measurement device. Write down temperature that your calibrated thermometer indicates. The more increments you have on a thermometer, the more accurate your estimates of temperature will be. Experiment No1 [Calibration of Thermometers] - Free download as PDF File (.pdf), Text File (.txt) or read online for free. Wait until the alcohol in the thermometer has stopped dropping and is at a steady level (this is called thermal equilibrium), and then mark with the marker where the alcohol is at. 2.1 Associated materials and equipment Repeat Steps 19-20 with water at a different temperature (preferably, significantly different). triple point of water 0.010 ºC) 6. This will be the distance between each increment of 10. Partnering with manufacturers, such as Vee Gee and Across, we can offer the highest quality Laboratory Thermometers to keep your lab safe, reliable, and accurate.