Need to drop 115VAC to 98.5VAC (or close to that)

Thread Starter


Joined Feb 28, 2021
I have 12 C7 bulbs wired 4 on 3 lines feeding from 1 AC line. I am turning each set of 3 bulbs ON or OFF using 4 SS Relays and a Arduino UNO controls the relay triggers. The problem is the bulbs are just a little to bright. So I used a motor controller to lower the AC voltage to get the look I wanted. I then unplugged the lights and measured the AC voltage coming out of the controller. 98.5 VAC to be exact. So I would like to drop the voltage close to that.
What would be the best way to do that? Dimmer switch maybe? Open to suggestions. Thanks


Joined Dec 29, 2008
... was thinking that you could simply insert a capacitor of appropriate size in series with each light bulb chain. ... Not too sure if you could find a suitable capacitor of the correct size and voltage capability for that purpose. ... The capacitor would be, in effect, an impedance, dropping the line voltage, in series with the light bulbs.
... just checked ... The price on AC capacitors that withstand that level of voltage seems to be prohibitive.
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Joined Feb 20, 2016
You could also use a transformer with a 20V secondary winding that is connected in series with the mains to the lamps, but in reverse phase so the 20V reduces the mains to the required level.