Digital thermometers are devices that are used to take temperature readings orally. Most of them are made such that they use their resistive aspects to take the readings.
As a result of this, they are the accurate and fastest. Digital thermometers may have different areas where they may come in handy. Some may use them for cooking and grilling, measuring the body temperatures or even the atmosphere temperature around you.
Most of the digital thermometers in the market use degrees Fahrenheit for their readings. And for this purpose, you may need to have knowledge in converting to degrees Celsius.
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Digital Thermometer Calibration: The Basics
For those who do not know the conversion here is a simple formula for this purpose:
(T (C) = (T (F) - 32) × 5/9). For this purpose, the thermometer needs to be calibrated often. It is an easy process and can be done personally. Below are some steps that one may use to do this.
T = Temperature
C = temperature in Centigrade
F = temperature in Fahrenheit
How To Calibrate A Digital Thermometer: When Should You Do It?
First of all, you have to know the right time that you need to calibrate your thermometer. Once you get your device for the first time, you need to calibrate it. This is to ensure that it will give accurate readings at all times.
Additionally, after being knocked or dropped, calibration is required to make sure it is still reading accurately.
After the impact, the calibration that was done on it may change. As a result, it is best to recalibrate it to the previous state. Different things may be measured at different extreme temperatures. When you are changing from very hot things to measure very cold things, it is best to also recalibrate the thermometer.
This will ensure that the next thing that you go to measure will not be slightly off from the correct reading. If you use it on a regular basis, it is best to often calibrate it to ensure it is not faulty.
Calibrating A Digital Thermometer: Initial Testing
In order to figure out if your thermometer is ok, there are two methods recommended to use. First, you have to check the freezing point. This may be done by filling a glass with ice that has been crushed.
Next, you have to add some clean water to the glass.
Stir it to ensure the ice dissolves. Give the mixture about three minutes and then insert the thermometer. You have to be careful that only the sensor is inserted. It is best to make sure that the sensor is fully immersed and in the midway point in the water.
One should avoid the thermometer touching the surfaces of the glass. This is to ensure that the reading is for the water and not the glass surfaces. After inserting the thermometer give it approximately thirty seconds and then remove see that the reading is 32 degrees Fahrenheit.
If the readings are as such this means that the thermometer is accurate. If this is not the case, then it is faulty and as such, it needs to be calibrated. It will give you a rough idea of how off the readings are. During the resetting process, you will have an idea of how much you need to calibrate it.
The second thing is checking for the boiling point. Here you will have to take about three cups of water. Put it in a pot and then boil it. As soon as the water is boiling, ensure that you insert the thermometer into the water. Ensure that the thermometer sensor is close to the center of the boiling water as possible.
It is best to place it away from the surface of the pot as possible. This will ensure that the readings are for the water specifically and not the surfaces. Give it about thirty seconds before you take the readings from the thermometer.
The thermometer should be reading 212 degrees Fahrenheit at this point. This will only be so for those at sea level. They may vary depending on the level above or below sea that you are in. The higher you go the lower the temperature that you may expect to have.
If the readings are as stated above, this means that your digital thermometer is accurate. If not so, there is the need for one to calibrate it. Depending on the reading achieved, you will know what amount you need to offset to attain correct readings.
Digital Thermometer Calibration Procedure
Here's a useful video on the calibration process. The thermometers will vary, but the basic concept is the same.
Different digital thermometers have different methods for the purpose of calibration.
First, there are those that have a nut or a screw for calibration. For this particular type, you have to adjust it manually to get the correct readings. During the testing, you will have got an accurate idea of how far away your thermometer is from an accurate reading.
The difference between the reading achieved and the expected reading is the one that you should use.
Using this particular figure, you will 'offset it' to get the right readings. It may be an addition or a subtraction. Some digital thermometers are able to recalibrate themselves with no more than press of a button, others will need manual actions.
Use your thermometer instruction manual to find out which type you have. For an automatic or manual model. you should retest after calibrating.
This will allow you to ensure that the readings that you have calibrated are the ones that reflect an accurate reading. If this is not the case you may be forced to repeat the whole process afresh.
Even when you have the correct results from the thermometer test, it is advisable to repeat the whole process regularly. This will be for the purpose of verification of the accuracy and precision.
The initial retest will give you an idea of how long you may need to wait to get a correct reading on your thermometer. Though most of the digital thermometers have been made to give results instantly, there may be an issue and the particular thermometer may have an internal delay. It is likely to me only a second or two, but it's worth knowing the limitations of your thermometer.