- Mon Jan 02, 2017 4:39 pm
#192730
I bought four 20-bulb LED holiday light strings, each powered by 3 AA batteries (thus 4.5V DC). I use them to light up two very small spruce trees, two strings per tree. In addition to a switch, there is a single 20 ohm resistor inside the battery box for each string. I have to manually turn on/off each of the four strings, which is a pain. I want to wire all four strings to, say, a 4.5V DC 500mA AC adapter, plugged into a timer. Can I just connect the four strings (with resistor still in place) in parallel to the adapter? If so, what should I do about the resistors? Four 20 ohm resistors in parallel means 5 ohms total and that would make the current larger... In conclusion: does the 4.5V 500mA adapter look like the correct power source, can I connect the strings in parallel to the adapter and what resistance set-up should I include? Thanks!