120 and 240Vac LED Indicator

Posted on Sep 9, 2012

This circuit, designed on request, has proven to be useful to indicate when the voltage in a power supply line is changing from 120V to 240Vac. It can be used in different circumstances and circuits, mainly when an increase in ac or dc supply voltage needs to be detected.

120 and 240Vac LED Indicator
Click here to download the full size of the above Circuit.

D3 illuminates when the line voltage is approaching 120V and will remain in the on state also at 240V supply. On the other hand, D6 will illuminate only when the line voltage is about 240V and will stay on because the latching action of Q1, Q2 and related

Leave Comment

characters left:

New Circuits



Popular Circuits

Beat frequency indicator
Automatic water tank level controller motor driver circuit
ADUC831 1.3MIPS 8052 MCU + 62kB Flash + 8-Ch 12-Bit ADC + Dual 12-Bit DAC
fm radio receiver
Digital Step-Km Counter
Radio Motor Controller Schematic
Discrete components stereo encoder circuit diagram