For all those that have an existing lamp base and are looking at buying a lampshade for it, this will be a very useful information. Before buying a shade for your existing lamp base, it is important to understand if the lampshade that you are buying will work with the lamp holder that you currently have. In almost all cases in India, a lampshade is fixed onto a lampbase by seating the shade holder ring onto the bulb / lamp holder and tightening it in place with a threaded screw that comes with the holder. Buying the wrong kind of shade would mean that your shade holder ring is too small that it does not fit into the holder or it is too big that it does not tightly fit into the holder.
Predominantly there are three types of lamp / bulb holders that are in use here in India :
Edison screw type holder (E27)
The E27 is the biggest of the holders that is in use and from what we have experienced, is being used prominently in all parts of India except south (where the traditional pin type holders are in use “most of the time”. As the name suggests, the holder comes with the threaded socket and the bulb comes with threads. The bulb is fit into the lamp holder socket by screwing the bulb into the socket through the threads.
For your lampshade to work with the holder, the lampshade holder inner ring should be atleast 41mm in diameter.
If you buy a lampshade that has a holder ring smaller in diameter than 41mm, it will not fit the holder.
Solution in case you do not want to return the lampshade : Change the bulb holder from E27 to E14 or B22 depending on what is the diameter of the holder ring. What are these E14 and B22 holders ? Continue reading to know more.
Small Edison screw type holder (E14)
This is very similar to the E27 holder, with the only difference that it is smaller in diameter. The E14 holder sockets are small in diameter and the bulbs themselves will have smaller threads that enable screwing in to the socket.
In the case of E14, the lampshade holder inner ring should be 27-28mm in diameter.
What if you have bought a lampshade with holder ring that supports E27 holder ? Fret not.
Solution : E27 to E14 adapters or converters are available in nylon and plastic. It is only a question of fixing the adapter into the 41mm holder ring to make it smaller to support E14 holders. Without hesitating, request your lampshade vendor to provide the adapter so that your lampshade can be used with your existing lamp base and holder. The Other option, is to change the bulb holder to E27.
B22 Pin type holder (B22)
If you notice, this is the most common type of holder that has been in use in India. The bulb comes with two pins and is inserted into the holder by pressing it in and turning it to lock it in place with the pins. These holders that are used on table lamps and floor lamps with me 100% of the time made of brass which makes it easier for you to identify.
Also, If you notice, the not so fancy white plastic holders that we use on our walls are mostly the B22 type holders. We would bet our bottom dollar on the fact that these types of holders would be used in almost every household in India. Just walk around your home, and am sure at least one of your wall fitting comes with B22 holders.
Now the important point. Your lampshade holder inner ring should be 25mm in diameter for the shade to snugly fit into the holder.
If in case your shade ring is meant for B22 and you have E14 or E27 holder, there is no two ways about it – You either have to change the holder to B22 or request your lampshade vendor for a replacement.
So before you buy your lampshade for an existing lamp, check the lamp for the holder in use and check with your vendor to ensure he is sending you a lampshade that will fit into your lampshade. E27, E14 and B22 – Just these and they can be easily identified.
Just remember – Wide thread is E27, Narrow thread is E17 and No thread is B22.