Why must TRUE-RMS

Nonlinear load requires measuring tool with features true-rms in order to read the signal accurately

Root Mean Square

Unlike the DC signal which has the actual value fixed, the actual AC signal has a value that is constantly changing periodically. AC signal measurements performed by searching for its DC equivalent value, equivalent value is known as the RMS or effective value. In electrical terms, the value would be equivalent to RMS AC DC its heating value.

The majority of measuring devices that currently circulating in the market is MEAN-tech measuring devices (Averaging Rectified). MEAN very popular method used because it has a calculation procedure which is easier and economical. In a pure sinusoidal signal, the value of the MEAN will be similar to the RMS value, so "can be said to be" worth the same. On the measurement of pure sine wave has a peak value of 1V (figure 1), showed that the value of 0.6366 (MEAN) approaches the value 0.7071 (RMS). MEAN-based measuring instrument will display the value obtained from MEAN calculation which is then multiplied by the number 1.11. The value of this multiplication results will be displayed on a display measuring tool.

When the signal is no longer sinusoidal...

Most modern electronic equipment using an AC voltage source that has been rectified. This load is commonly known as non-linear load. Non-linear load has a characteristic where the current signal drawn from the netting PLN no longer proportional to the sine wave voltage and distortion (figure 2b), compared with the image 2a.On development, the expansion of non-linear load has penetrated into the world along with the widespread use of industrial inverters and switching power supply. Form of the output signal of the inverter was no longer sinusoidal, but rather a series of square signals such as images 2c. Under these conditions, the process of trouble shooting will face problems if we do not use appropriate measuring instruments. Errors in the selection of measuring instruments can lead to inaccuracies in measurement results. For this reason measurement is required which is able to read the RMS value at all signal conditions without exception

Still Relevant? MEAN with RMS on condition of the electricity now...?

MEAN-based measurement tool designed to calculate the value of this approach to the RMS value of the linear loads such as induction motor, heater and incandescent lamps. Linear load will have a sinusoidal flow pattern so that the meter reading will be close to the RMS value of the signal. However, the MEAN method will not be accurate when applied to non-linear loads, why? The answer is simple, non-linear load current wave patterns that no longer sinusoidal. When the nonlinear load is measured with a measuring instrument tech MEAN, then the result will be much smaller readings. Some sources state that the deviation values can be read to reach up to 40% lower than the true RMS value.

Why should be read in RMS

Components in electrical systems such as fuse, circuit breaker, bus bars and the like ratified in RMS current. Ratification is associated with a particular aspect of endurance against heat dissipation. For example, we would inspect overloading the electrical path. So we should know in advance how the rms value of currents flowing on the path. The measurement results and then we compare with the value of ratification (rated value) is usually indicated on the label. When was the current that flows greater than the limit detectable ratification, we can conclude the line overload. This benchmarking process will not be a problem if when making a measurement, we use a true rms clamp-featured.True rms Clamp has the capability to perform calculations according to formulas rms heating value. That is, like any form of current signal will not affect the reading of the rms value. But the measure would cause new problems if we do this by using a measuring instrument based MEANS. MEAN-tech measuring instrument will give the value of reading with a margin of error of up to 40% lower, depending on the type of signal. We can imagine when a bus bar with a limit of 1000 A rms ratification energized distorted and detected by a clamp with a value of 800 A. MEANS Then the rms value of actual current flowing in bus bar can be reached up to 1000A.