Type of Multimeters
Points : Type of Multimeters, Analog Multimeter, Digital Multimeter
Basically there are two types of multimeters:
1. Analog Multimeter
2. Digital Multimeter
1. Analog Multimeter
The digital meters work on the principle of quantization. The analog quantity to be measured is first
subdivided or quantized into a number of small intervals up to many decimal places. The objective of the
digital instrument is then to determine in which portion of the subdivision the measure and can thus be
identified as an integral multiple of the smallest unit called the quantum, chosen for subdivision. The
measuring procedure thus reduces to one of the counting the number of quanta present in the measurand. The
digital instruments indicate the reading directly in decimal numbers. This is done by using a “digital
display device”.
2. Digital Multimeter
Basically the digital meters use the “Digital Voltmeter” (DVM). These display the value of a.c or d.c
voltages being measured directly as discrete numerals in the decimal number system. If current is to be
measured, it is passed through a standard resistor. The voltage appearing across the resistor is then
measured with a “DVM”. The value of current can thus be known from the counts appearing on the counters of
the readout system of DVM. Similarly a resistance is to be measured, a fixed current is first passed
through a resistor. The voltage drop across the resistor, which is proportional to the resistance is
measured through DVM. Other physical quantities may also be measured through DVMs by using suitable
transducers to feed the input of the DVM.
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