Detection Technology
The precision of a digital megohm meter
It is important to use megabytes to provide correct measurements. It is even more important to know what these measures mean. Accuracy and precision ensure that the measurements you make will be useful; Higher precision allows for easier repeatability, and higher precision means your reading will be closer to perfect.
What is the accuracy of a digital megohm meter?
Accuracy is the maximum allowable error that occurs under certain operating conditions. It is expressed as a percentage of how close the measured value displayed is to the actual (standard) value of the measured signal.
The precision of a particular digital megogram is important, depending on the application. For example, most ac power lines vary in voltage range of ± 5% or more. An example of this variation is a voltage measurement at a standard 115 V AC socket. If only a digital megohm meter is used to check whether the socket is energized, it is suitable to use a digital megohm meter with measuring accuracy of ± 3%.
Some applications, such as automotive, medical aviation, or calibration of specialized industrial equipment, may require greater accuracy, with readings of 100.0v ranging from 98.0v to 102.0v with an accuracy of ± 2% on a digital Megabyte meter. This may be good for some applications, but it is unacceptable for more sensitive electronic devices.
Precision can also include the specified number of bits (counts) added to the base precision level. For example, an accuracy of ± (2% + 2) means that a 100.0v reading on a megohm meter can range from 97.8v to 102.2v. Many applications can be realized by using digital megohm meters with higher precision.
The basic dc accuracy range of Fluke portable digital megohm meter is 0.5% to 0.025%.
How accurate is the digital megohm meter?
Precision is the ability of an exponential Megabyte meter to provide the same measurements repeatedly.
A common example for explaining accuracy is the arrangement of holes in a target at a range. This example assumes that a rifle aims at the bull's eye of the target and fires from the same position each time.
If the hole is tightly packed but outside the bull's eye, the rifle (or shooter) can be considered accurate but inaccurate.
If the hole is tightly plugged into the bull's eye, the rifle is accurate and accurate. If the holes are randomly distributed over the entire target, they are neither accurate nor accurate (nor repeatable).
In some cases, accuracy or repeatability is more important than accuracy. If the measurements are repeatable, the error pattern can be identified and compensated.
What does measure resolution mean?
Resolution is the minimum increment that the tool can detect and display.
For the non-electrical example, consider two rulers. The resolution marked 1/16 inch is higher than that marked 1/4 inch.
Imagine a simple test of a 1.5 V household battery. If the digital megohm has a resolution of 1 mV in the 3 V range, you may see a change of 1 mV when reading the voltage. Users can see variations as small as one thousandth of a volt, or 0.001 in the 3 V range.
Resolution may be listed as the maximum resolution in the meter specification, which is the minimum that can be distinguished in the meter's minimum range setting.
For example, a maximum resolution of 100 mV (0.1 V) means that when the megotometer range is set to measure the highest possible voltage, the voltage will be displayed to the nearest tenth of a volt.
As long as the measured value is within the set range, the resolution can be improved by reducing the range setting of the digital megotometer.
What is the range of a megohm meter?
The range and resolution of a digital megohm are related and are sometimes specified in the specification of a digital megohm.
Many megabytes provide an automatic range feature that automatically selects the appropriate range for the range of measurements to be made. This provides both meaningful readings and optimal measurement resolution.
If the measured value is higher than the set range, the megotometer will display OL (overload) to obtain the most accurate measurement at the lowest possible range setting without overloading the megotometer.
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