Maintenance Of Incandescent Miniature Light Strings


Basic Lighting Rules of Thumb

All incandescent miniature lights work in the same fashion. They are comprised of circuits which may be from one circuit up to five. All miniature lights are now constructed with the ability to remain lit if one bulb burns out. This is because the circuit is not broken when a filament is burned out. Each bulb contains a "shunt" in its base which allows the electrical current to pass through the set if all bulbs remain seated in their respective sockets. If, however, a bulb is broken, loose, missing or several of the lights are burned out, the circuit will be broken and the lights will not work properly. It is also possible for the shunt to become damaged which would also cause the set of lights not to work properly.


If the strand of lights you are using is one-circuit (35 and 50 lights per strand), the entire light strand will not work. If you are working with two or more circuits (70, 100, 140 or more lights per strand), then only the circuit that is affected by the break in the circuit will not work and the others will remain lit. Keep in mind that problems can occur at the same time in different parts of the circuit causing more than one circuit to not work properly in the same light strand.

If you have checked your lights carefully and the strand will still not fully light, check the fuse in the male plug. Keep in mind that if the fuse in one set of lights is blown, then the other light strands plugged in after it will not work either.


Guidelines when working with incandescent miniature lights to enable the longest lifespan of lighting strands:


1.  ALWAYS replace burned out bulbs immediately. If you don't, the remaining bulbs will burn out quicker because the energy that was being used for the burned out bulbs is the transferred to the good bulbs. As the bulbs continue to burn, each light will burn out faster than the one before it until the entire circuit stops working.

2.  NEVER plug more than three sets together. The design of miniature lights only allows three sets to be connected together. If more than three circuits are connected, the fuse in the plug will blow, causing the entire strand to not work properly. 

3.  When lighting, be careful not to wrap the wire to taut, because this can cause the wire to become "crimped." This weakens the wire and can cause cracks in the wire insulation thus exposing the wire. 

4.  NEVER cut the wire. An exposed wire can cause short circuits and break the circuit causing the lights to work improperly. 

5.  ALWAYS replace bulbs with the same voltage bulb. Failure to do so causes the remaining the remaining bulbs to burn more quickly and will cause the light strand to work improperly.

    •  How to know what voltage of bulb you are using: You will notice the bulb you replaced burns brighter or dimmer that the other bulbs.
    •  An easy formula for calculating bulb voltage is: Take the number of lights on one circuit and divide that number into 120 (the voltage of the current of electricity) (35 light set = 3.5 volt; 50 light set = 2.5 volt; 100 light set; 2 circuits = 2.5 volt; etc.)