Voltage Sensor Working and Its Applications

Generally, a sensor is an electrical device used to detect as well as respond to a particular type of signal like optical or electrical. Implementation of sensor techniques in voltage or current has become an outstanding option toward the measurement of voltage & current methods. The advantages of sensors over conventional methods for measuring mainly include less size and weight, high safety, high accuracy, nonsaturable, eco-friendly, etc. It is feasible to merge both the current and voltage measurement into a physical device with tiny and solid dimensions. This article discusses an overview of the voltage sensor and its working.

What is a Voltage Sensor?

This sensor is used to monitor, calculate and determine the voltage supply. This sensor can determine the AC or DC voltage level. The input of this sensor can be the voltage whereas the output is the switches, analog voltage signal, a current signal, an audible signal, etc. Some sensors provide sine waveforms or pulse waveforms like output & others can generate outputs like AM (Amplitude Modulation), PWM (Pulse Width Modulation) or FM (Frequency Modulation). The measurement of these sensors can depend on the voltage divider.


This sensor includes input and output. The input side mainly includes two pins namely positive and negative pins. The two pins of the device can be connected to the positive & negative pins of the sensor. The device positive & negative pins can be connected to the positive & negative pins of the sensor. The output of this sensor mainly includes supply voltage (Vcc), ground (GND), analog o/p data

Types of Voltage Sensors

These sensors are classified into two types like a resistive type sensor and capacitive type sensor.

1) Resistive Type Sensor

This sensor mainly includes two circuits like a voltage divider & bridge circuit. The resistor in the circuit works as a sensing element. The voltage can be separated into two resistors like a reference voltage & variable resistor to make a circuit of the voltage divider. A voltage supply is applied to this circuit. The output voltage can be decided by the resistance used in the circuit. So the voltage change can be amplified.


The bridge circuit can be designed with four resistors. One of these resistors can be subjected to the voltage detector device. The change in voltage can be directly exhibited. This difference alone can be amplified but the difference within the voltage divider circuit not only amplified.


Vout = (R1/R1 + R2) * Vin

2) Capacitor Type Sensor

This type of sensor consists of an insulator and two conductors within the center. As the capacitor is power-driven with 5 Volt, then the flow of current will be there in the capacitor. This can create revulsion of electrons within the capacitor. The difference in capacitance indicates the voltage and the capacitor can be connected within the series.


Vout = (C1/C1 + C2) * Vin


The applications of this sensor include the following.

  • Detection of power failure
  • Detecting of load
  • Safety switching
  • Controlling temperature
  • Controlling of power demand
  • Detection of fault
  • Variation of load measurement of Temperature

Thus, this is all about voltage sensor which can be used to detect the range of voltage in any device. It decides the electrical charge within any device. The working principle of this sensor mainly depends on the principle of either capacitive or resistive. Here is a question for you, what are the advantages of voltage sensor?