An attenuator voltmeter is defined as an instrument used for measuring the electrical potential difference, also known as voltage, between two points in the electronic circuit of different attenuators such as an optical attenuator and digital attenuator. Voltage is referred to as the electric potential energy per unit charge. It is responsible for driving a current from one electron to another electron. The corresponding International System of Units (SI units) for voltage is volt. The attenuator voltmeter can measure direct current (DC) or alternating current (AC).
In technical terms, all voltmeters are considered ammeters. This is because they measure electric current rather than voltage. Voltage is only measured when the electric current is transmitted in the electric circuit via resistance. Voltmeters are originally called galvanometers. Voltmeters are also known as multimeter because they also measure resistance and current.
The two types of attenuator voltmeter are the digital and analog voltmeters. A digital voltmeter usually features a voltage reference, an analog-to-digital converter, a power supply and a digital display unit. This kind of voltmeter directly displays numerals through the analog-to-digital converter. The digital display system could be a light emitting diode (LED) or a liquid crystal display (LCD) panel. There are several factors that may affect the accuracy of measurement of a digital voltmeter. Some of these factors include temperature and supply voltage variations. Users now prefer a digital voltmeter over an analog one because of its accuracy. To maintain its accuracy, periodic calibration of the voltmeter against a voltage standard is recommended.
Basically, an analog voltmeter contains a galvanometer, or current meter, which is in series with a high resistance. An analog voltmeter displays values on a dial, usually with a moving pointer or a needle. This kind of voltmeter may be employed to locate excessive resistance that may indicate an open circuit or ground. The impedance is the internal resistance of an analog voltmeter. This is commonly expressed in ohms per volt. An analog voltmeter is connected in parallel with the circuit being tested. This allows the meter to tap a small amount of electric current.
An attenuator is defined as a device which reduces the amplitude or power of a signal without distorting the signal’s waveform. This electronic device is used in audio and radio signal circuits. To measure the voltage difference in the attenuator circuit, the positive input terminal and negative input terminal are connected to a location in the electric circuit. When the attenuator voltmeter is already attached to the electric circuit, the circuit will be disturbed, which leads to change in the voltage being measured. The disturbance should be negligible enough so that it will not create significant change in the voltage. Some of companies that manufacture voltmeters are Onesto Electric Co. Ltd., China Electronics Zhejiang Co., Sunlogic Electrical Appliance Ltd., Tons International Ltd., People Ele. Appliances Group, Zhejiang Taizhou Wangye Power Co. Ltd., Shanghai Chenchang Power Technology Co. Ltd., Shaanxi Xieli Photo Electric Instruments Co. Ltd., Dongquan Zhengyang Electronic Mechanical Ltd. and Chac Technology Co. Ltd.