This circuit can monitor direct or alternating currents. Resistor R1 is calculated so that the voltage drop with the desired current is approximately 1.8 V if the LEDs are red. The maximum current must not exceed the capacity of the LED.
This circuit can monitor direct or alternating currents. Resistor R1 is calculated so that the voltage drop with the desired current is approximately 1.8 V if the LEDs are red. The maximum current must not exceed the capacity of the LED.