Digital of Volt Meter models gauging of DC or AC voltage in the form of number discrit in the place of deflection of continuing on a scale indicator needle like in analogue devices. In many directing usages with number is thing profiting because lessening read error of man and interpolation error, eliminates error paralaxtion, enlarges read speed and often complements output in the form of digital according to for processing and record-keeping hereinafter.
DVM is an instrument pledged and accurate which can be applied in many gauging usages in laboratory. Because development and retouching of modules integrated circuit (IC), scale, requirement of power and the price of DVM has decreased drastically so that DVM actively can compete to instrument of other conventional analogue, in portability and also price.
Quality Of DVM which is uppermost can be depicted by arising some of operation characteristics and performance characteristic that is typical. Specification of following not all applying at a certain instrument, but they really express valid information about this present condition:
1. Input ambit: from less lebih1, 000000 V to 1000, 000 V, with election of ambit automatically and indication of overload.
2. Accuracy of absolute equal to 0, 005% from read.
3. Stability line: short-range 0, 002% from read for period 24 hours; length reach 0, 008% read for period 6 month.
4. Resolution: inner 1 10 ranks 6 (1 micro uF can read at input ambit 1V).
5. Input characteristic: typical input resistance is 10 MOHM; input capacity is 40 pF.
6. Calibration: internal calibration standard enabling calibration doesn't base on measure circuit obtained from source of reference stabilized.
7. Output signals: shallow command enables output of towards printing unit ( printer) output BCD (Binary Coded Decimal = each decimal numbers of its(the number expressed with 4 beet) for digital processing or record-keeping.
DVM can be grouped through some categories:
a. DVM ramp ( ramp type DVM).
b. DVM merger type ( integrating DVM).
c. Balance DVM of continuant ( continues balance DVM).
d. DVM with approximate successively ( successive approximation DVM).
