How to choose the right lights this Christmas & installation precautions

Image Source
http://hairloves.com/92-christmas-lights-sale-image-idea

Christmas is coming closer and its time to deck our homes up with decorations and lights to add to the Christmassy feeling. Today the market is loaded with a ton of variety of lights but the sad state of affairs is that most of the sellers out there neither have no proper knowledge of the products they are selling nor any electrical knowledge considering the power consumption and safety standards. The intent of this article is to educate the masses about decorative lights who don't have in depth electrical knowledge.

When we go out shopping for lights we try to get the best deal bargaining but many a times we don't realize the downsides after we actually use the lights. So considering the wide range of products that we have, I would broadly classify them as good quality long lasting types and the cheapy, unreliable and dodgy Chinese products. 


The Reliable and Lasting lights

Locally made lights

I would consider the LED serials that are locally manufactured in India as reliable and lasting because of their construction, better grade of wire as compared to Chinese lights and the ability to repair them. The look similar to the locally made tungsten bulb based lights which had coloured caps but transparent here because the LED's produce different coloured lights. Off course repairing them would need some basic tools like soldering iron, multimeter, wire snips etc. but there will be local repair shops who will fix them for a nominal amount. This is the main reason these lights are commonly used by commercial light decorators. Their constriction is robust and has room for some rough handling any suitable for outdoor use. These may cost almost double than the Chinese string but will be value for your money if you wan something long term. Unfortunately there are no branded decorative light manufacturers in India that sell such products at reasonable prices.



Cheapy, unreliable and dodgy Chinese lights

Apparently the Chinese know the Indian market well for lights and have successfully managed to sell their products because of the competitive pricing. But the fine print is that these products are not long lasting, reliable and most importantly unsafe. Cheaper the lights higher would be the safety risks. Most of these lights use a very low grade wire and insulation which is not up to the mark as per the electrical standards. The job of the wire insulation is just not to protect from electrical shock but should be fireproof to a an extent. Most of them are not fireproof at all and could be catastrophic if installed next to paper/cardboard/plastic material that can catch fire easily.

The lights above are the most notorious tungsten based (or regular bulbs) serial lights. They come in single colour and are very cheap (cost about 30 rupees a string at Crawford market). These produce excessive amount of heat and are more prone to fires if used over a long period of time. In addition the wire quality is poor that they don't last for more than a season.

Coming to LED lights now, it has been quite a while since they have flooded the Indian market. I would say most of the LED light stings are safer than the traditional one's mainly due to lesser heat being generated. But they suffer the same drawback, they cannot be repaired if they fail and have to be handled with extreme caution.

The traditional rope lights are also available in LED bulbs which serve as a good candidate for outdoor lighting. The drawback of these is that they are not repairable and have to be handled carefully. They are suitable for applications where the installation is permanent.

The traditional LED strings like the ones below are best suited for indoor use especially on Christmas trees. The use the mysterious box that has a reset button which has been used in many lights for nearly two decades. These also suffer the same problem of not being repairable as they bulbs have the insulation moulded around them. The wires are so thin that you cannot strip the insulation off.

Pixel LED lights

This is a different kind of LED lighting that is picking up in the consumer market in India recently. They are called pixels because each bulb can generate multiple colours. In addition it is possible to control the colours with simple controllers sold in market  or Arduino boards popularly used by electronic hobbyists.

Available with belt for easy installation

These can have controllers that produce beautiful effects with different colours as shown below. Its not necessary to have a setup like the building below even if you run a single strip along the border it will look good. These come in lengths of 8 or 16 feet and are little pricey. They work on 5 volts so its powered by a DC power supply. I would categorize this as safe and good construction Chinese lights. Although they may not be easily repairable they can still be fixed. The bulbs are connected in a parallel and controlled by a separate signal line.

Considerations while purchasing lights:

1. Power Consumption: If you are concerned about electricity bills then avoid lights that are on continuously and purchase the ones that flicker. These are recommended as they consumer lesser power & generate lesser heat.
2. Electrical safety: Ensure that the wires of the lights look strong and are not too fine.
3. Build quality: Do not buy if they look brittle or faded. These are indicators of old stock or poor quality lights. 
4. Length of light strings: Make sure you check the length of the light string is suited to your requirements. Most Chinese lights don't have these mentioned correctly on the box and most dealers just fire any lengths when asked. There are cases they quote length in meters once its actually feet. 
5. Light colour emitted out: LED's that are manufactured today have a lot of variance in terms of colours. Some colours are extremely unpleasant indoors. Avoid blue & white lights especially in mixed colour strings as they are extremely bright as compared to red, yellow and green.

Considerations while setting up lights: 

• Make sure the wires are not hung on sharp hooks where there are chances of wires getting cut.
• Ensure power supply boxes, extension cords and connections are placed in a dry area and not in the reach of any person.
• Would recommend using lights on extension boards with a fuse (2 amp rating for 2-3 serials). This would serve as an additional protection in event of any short circuit due to failure in the lights.
• Keep lights away from inflammable materials like dry grass, cardboards etc.
• Use electrical insulation tape to seal joint wires. Cello tape & masking tape are not fireproof and should not be used.

Some myths on Christmas lights:

"LED bulbs work on low voltage so they are safe to touch the contacts while testing" : Its true LED work on low voltage but the bulbs are connected in series so it get divided among the 50 odd bulbs and hence each bulb is comfortable with the right voltage. However you may think that what if I touch one of the bulb points....just don't be silly as your body resistance will be more than that of the bulb and hence you will have a larger voltage across your body relative to the series circuit. If you haven't got what I said then please don't touch the damm exposed wires in a serial set when powered.

"Serial lights can be repaired by shorting broken/burnt bulbs" : By theory the bulbs will light up, however you are increasing the strain on the remaining bulbs (the same way you would zap yourself touching any exposed wires in above myth). Also using the above technique to repair lights would increase the chances of slow burnout and in worse case start a fire. (Here's where the low quality insulation will be a catastrophe )