I am in the process of wiring up my control panel, and have decided that I want lamps to indicate which blocks I have on. I have figured out how to do it using DPDT switches, but now the only problem is the lamps.
I bought some 120VAC lamps from Radio Shack, thinking that I could use them from the AC terminal of my power pack (I have an older one that I am using to dedicate the power from).
However, after some trial and error, I have found that these will not work from the power pack, but must be plugged into a regular house socket.
I also found out that the AC terminal is too much for LED’s.
Are there any lamps that I can use that will work from the AC terminal?
Or is it possible or even safe to set up a distribution for the lamps using telephone wire(like is set up for blocking) to run off of a regular socket?
Thanks in advance for your help.
Ah well thats why your LED’s didn’t survive. LED’s always have to have a resistor in series with them to limit the current otherwise they’ll burn out instantly.
You only need a resistor in series with a light bulb if you’re running it on a higher voltage than it’s intended for (the resistor uses up some of the voltage so bulb gets less) The easyest way to decide is to just try a few different values of resistor untill you get the brightness you desire. I’m guessing that around 10 ohms would be right for a 12V light bulb on the 18V accessory terminals although you may need less.
A 1000ohm resistor works well for LED’s
Just a suggestion - I did this with my control panel using Light Emitting Diodes (LEDs) and a battery holder (for power) from Radio Shack. LEDs are cheap, last forever, and draw very little current. I get about 4+ months use from a pair of AA batteries. You could also buy an inexpensive AC/DC converter (like those used to power portable CD players) and do away with the batteries.
kornchex…Whatever you do, don’t run any lightweight wires [like telephone wires ] off a regular 110-120 volt household socket…This is EXTREMELY DANGEROUS. High risk of shock, rapid excess heat, and FIRE !
Best to have no 110-120v power in your panel anywhere, except main plug-in cords for power packs.Too dangerous, and the wire you need is too large…[the absolute minimum is lamp cord size. ]
You can get white or colored bulbs at a hobby shop, or at Radio Shack that are 12 volts, that will run off your AC terminals, or the fixed DC terminals of your power pack.See if you can return those high voltage lights.
Happy New Year & best regards / Mike
Thanks to both of you, especially the part about not using 110-120v. I was concerened, which is why I didn’t do anything yet.
So I am looking fot 12 volt bulbs…OK.
Thank you again.
What size resistor did you put in series with the LED when you tried it? You should be able to run the LED off of the AC termonal just fine.
Other option is get 12V bulbs from radio shack. Probably add a resistor to those too as most powerpacks give 18V to the ac terminals.
Resistors?
I am not familiar with how to use resistors.
Could you please give me some more information on their applications here.
I have installed 12V bulbs from RS, and they are working well.
Thanks.
Thanks Paul, I will certainly have to give that a try.