What is the name of this LED ?

Thread Starter

Zanac-X

Joined Dec 23, 2011
51
ok....so its a bulb but i didnt get any info about it like its resistance, its max voltage or can i operate it on AC-DC
 

t06afre

Joined May 11, 2009
5,934
A conventional light bulb can operate on both DC and AC. For AC use the RMS value. Regarding the specs. I do not have any clue at all.
 

ErnieM

Joined Apr 24, 2011
8,377
It's a standard Christmas light, possibly a blinker due to the lower darker arm. The arm heats up when the bulb is lit, so it moves and beaks contact. Bulb goes off, cools, arm moves back, bulb lights, cycle repeats.

An oft misunderstood part of these bulbs is the coil of wires around the two leads to the filament: these are there to short the bulb if the filament burns out. Note it is NOT a resistor, and if you compare the resistance of a burned out bulb to a working bulb the burned out one has a lower resistance!

This is due to some interesting physics: these bulbs run in a series circuit of (typically) 35 or 50 bulbs. When a bulb burns out and opens it blocks the passage of current, so instead of seeing 1/35th or 1/50th of the line voltage it sees the full line voltage. This causes an arc to the thin insulation on this coil, which then arcs and welds itself across the now open filament, thus letting the other 34 or 49 bulbs remain lit.

Obviously as more and more bulbs burn out the remainder run hotter and hotter. Eventually they will fail machine gun fashion but it does provide a more graceful degradation of functionality (and a chance for repair to the very observant).

The best way to get the voltage this bulb runs at is to get the light string it came from and count the bulbs. Divide the line voltage b that number and you have it's operating voltage.
 

MrChips

Joined Oct 2, 2009
30,810
It's a standard Christmas light...
...so instead of seeing 1/35th or 1/50th of the line voltage it sees the full line voltage.
When one filament blows, the one lamp will only see 1/35 or 1/50 of the line voltage.

Typically, such a Christmas tree lamp will run on 1.5 to 3V AC or DC.

You can tell if it is a flasher or not by looking closely to see if there is a bi-metallic circuit breaker in the bulb.

Ordinary Christmas tree bulb:





Christmas tree flasher:

 
Last edited:

DerStrom8

Joined Feb 20, 2011
2,390
The others are half-right. It is a standard incandescent christmas light bulb, not an LED. It is not a flasher, however. A flasher has a third "arm" that moves back and forth between the contacts, whereas yours only has two. This is basically what yours is:



You can generally assume that a christmas light bulb runs on about 2.5 volts, but it varies widely.
 

KJ6EAD

Joined Apr 30, 2011
1,581
The last time I bought incandescent Christmas lights (a long time ago) they were all wired in series groups of 20 so the bulbs were all 6V.
 
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