Alternator Current/Voltage Monitor

Wichit Sirichote,

Monitoring the DC electrical current/voltage from the alternator with Winson Hall sensor

The device for monitoring electrical current/voltage is built with nano328 board and the Hall senor Winson 1600. The sensor provides isolation measurement by detecting the magnetic field produced from DC electrical current. The current sensor, Winson 1600 is capable of detecting up to 100A. The sensor sensitivity is 22mV/A. The signal output from the sensor is measured by the analog input A0 of the nano328 board. The additional voltage measurement using simple voltage divider is also provided. The reading is displayed with 4-digit LED TM1637 board.

Winson 1600 current sensor and remote display

Hardware features:

Hardware schematic (click to enlarge)

Hardware: The current sensor, winson 1600 is connected to J2, VDD is supplied with +5V. The output signal VOUT is tied to A0, analog input of the nano328 board. The voltage sensor is simple voltage divider, R1 and R2. The voltage signal is tied to A1. SW1 selects display between Current and Voltage readings. The logic input 0 or 1 is detected by D9 digital input pin.

Remote display is TM1637 4-digit LED board. It needs two signals, TMCLK and DIO. The library TM1637 provides interface functions for displaying the readings in decimal units. Diode D1 prevents wrong power supply connection. The remote display is connected J1 using multicore or ribbon wire.


Detecting DC current, 5.2A


Remote display


TM1637 display board


Display 14.2V




U1 MEGA 328 NANO control board
D1 1N4001, Silicon diode

Resistors (all resistors are 1/8W +/-5%)

R1 10k
R2 1k

Additional parts

SW1 micro selector switch
Winson 1600, 0-100A Hall sensor
TM1637 Display module



Schematic , source code

More technical information, please contact Wichit Sirichote,



Last updated February 22, 2023