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gocats7
12-14-2008, 07:23 PM
OK, so I'm new to this so I know this will be a wtf question for most. I have a couple of strands of chasing lights that my wife loves and I have kinda let them go over the years because I didnt know much about it all. Well, this year I am trying to figure it all out and get them back in shape (there were probably close to 50 bulbs out between the two strands). Well I started replacing bulbs and some of them when I replaced them were very dim so I used "different" bulbs but I dont know exactly what the difference was or how to tell the difference until I put them in and see it.

I assume its different voltage bulbs, but how do you know which is which by looking at the bulbs and also can you just tell by looking at a set or something?

rstehle
12-14-2008, 11:03 PM
You would need to count the total bulbs, and the number of channels of chasing. 140 bulbs, and 4 channels is very common. That would mean that you have 35 bulbs per channel. You will want to replace your burned out bulbs with bulbs from a strand of the same count. Lowe's carries 35 count bulb strands (unless they are out due to end of season).

omzig
12-15-2008, 10:18 AM
I don't think that there is any way to tell what the voltage of a bulb is by looking at it. I just looked at a bunch of them that I have collected over the years, and the only one that looks any different are the 12V, which have a much longer filament.

Common mini light voltages and the string counts that use them:
2.5V - 50, 100, 150
3.5V - 35, 70, 105
6V - 20
12V - 10 (tree toppers)

When I open a box of mini's, I always put the replacement bulbs that come with them into separate containers according to what the voltage is.

bmcgeeny
12-15-2008, 11:19 AM
I don't think that there is any way to tell what the voltage of a bulb is by looking at it. I just looked at a bunch of them that I have collected over the years, and the only one that looks any different are the 12V, which have a much longer filament.

Common mini light voltages and the string counts that use them:
2.5V - 50, 100, 150
3.5V - 35, 70, 105
6V - 20
12V - 10 (tree toppers)

When I open a box of mini's, I always put the replacement bulbs that come with them into separate containers according to what the voltage is.

I don't know who else might have 10,000 plus spare bulbs, but I find pulling bulbs from bad strings, checking with a 2.5 v tester I made from a wall wart, sorting by color, voltage, brightness keeps me from eating popcorn while watching reruns of Gilligans Island.

That is the only way I know to check them. Power and resistance. With a little experience you can plug them in and tell just by the glow. 3.5v from a 35 light string are pretty dim at 2.5 v. 2.5 regulars look regular and 2.5 super brights look, well super bright. Mostly this is with clear bulbs, but I have seen a few 2.5v colored lights that very.

It is unlikely that you are putting a 2.5v bulb in a 3.5v string. That would be VERY bright and burn out very quickly.

rlilly
12-15-2008, 01:00 PM
Ernie posted a useful chart to help in identifying bulb voltages.

http://www.doityourselfchristmas.com/forums/showpost.php?p=44247&postcount=6

Photovor
12-15-2008, 01:08 PM
I don't know who else might have 10,000 plus spare bulbs, but I find pulling bulbs from bad strings, checking with a 2.5 v tester I made from a wall wart, sorting by color, voltage, brightness keeps me from eating popcorn while watching reruns of Gilligans Island.

That is the only way I know to check them. Power and resistance. With a little experience you can plug them in and tell just by the glow. 3.5v from a 35 light string are pretty dim at 2.5 v. 2.5 regulars look regular and 2.5 super brights look, well super bright. Mostly this is with clear bulbs, but I have seen a few 2.5v colored lights that very.

It is unlikely that you are putting a 2.5v bulb in a 3.5v string. That would be VERY bright and burn out very quickly.


Not to derail this conversation, but I've taken sets that may have bad sockets, and just pulled the bulbs too. I've also gone a step further, by cutting off the plug ends, and un-wrapping the traveler wire that goes the length of the set. Good for little spares here and there. I just can't bring myself to throwing anything away that still has bulbs in it :-)

gocats7
12-21-2008, 11:20 PM
First time back to the board, thanks to all that posted. This gives me something to go on for sure. Hope your shows are going well, Im really happy for 1st year.

dadams14
01-03-2009, 09:42 AM
I have some older 100 light sets (2 sets of 50 in parallel) and some newer ones and I cannot substitute bulbs from one to the other. One way it blows the filament out and the other way the light shows very dim.
The only explanation I can come up with is the resistance of the filaments is different . therefore the set using the lower resistance bulbs will have a higher current flowing through them and therefore use a higher wattage of power. (ohms law)
But each bulb in the correct circuit still drops approx 2.2volts
I puzzled over this for a while when I first encountered it.
Thanks
Dennis