Shorten mini lights?

[James Hill]

Hello everyone,

I am by no means an electrician but here is what I want to know. I want to light my 'Tune Into' sign with a string of mini lights and have it connected to a controller. I want to shorten a length of mini incandescent lights. The string is in series using 50 lamps at 2.5v, 0.5w / lamp. I want to drop the string to 15 lamps. I understand I either need a resistor in line (but do not know how to figure out the size) or change the lamps to a different volt/watt. I don't know what size of new bulbs to use or what resistor required.

 

35 lights removed---35 x 2.5v = 87.5v

                                35 x 0.5w = 17.5w

 

But don't know what this tells me.

 

Thank you in advance everyone.

Edited October 14, 2015 by James Hill

[jerrymac]

Best be is go down to Walmart or Hobby Lobby. They sell 15 and 20 string lights.

[Little_b]

The Dollar Store sells short strands as well.

[Dennis Laff]

Christmas LEDs sells white lights starting at 10 bulbs per string and up from thelr

[Max-Paul]

Or put a sock around the 35 lamps and hide them in back of the sign. But what ever you do, let them breath or your going to have a real hot spot on your hands.

[jerry72]

You would need a 500 ohm resistor at 14 watts. I would do as the other suggested and go buy a 20 bulb set and just get some M5 caps and black out the other 5

 

http://www.gtsparkplugs.com/Dropping_Resistor_Calc.html

[James Hill]

Thanks everyone. I was thinking of using some of my scrap lights but will keep my eyes open for the 20ct lights...here in Thunder Bay everyone has the Halloween stuff right now...only orange and purple lights. Happy lighting everyone!!!