by ericmark »
Mon Mar 07, 2011 10:37 am
The normal method I use is to replace the block connector in the florescent lamp with one with an extra terminal on it.
A standard ceiling rose has four connections.
Earth - Often a different type of terminal to rest of a clamp type.
2 connection Switch terminal often has black wire (should be sleeved with red or brown) this is from the switch to lamp and very important that it does not get mixed up with rest. Be careful to mark well.
3 connection line terminal centre this has the supply in, supply out to next lamp, and supply to switch. It does NOT connect to lamp and will need extra terminal when rose is removed. Exception is when an emergency lamp is used this is always live and is used to charge batteries.
3 connection neutral terminal this has neutral in, neutral out to next lamp and neutral to lamp. It normally does not connect to switch.
For a garage often we don't wire to lamp first and then to switch but go to switch and then to lamp. Also with a garage often we don't have a 6A supply so we need to fuse down. Plus going through a normal light switch gives no provision to connect neutral.
Hence with a garage we often use a switched fused connection unit (FCU) this does have a neutral connection, it also has provision for using a 3A fuse and you can lock off the light so you can work on it without switching off the whole supply.
There is not a right and wrong way just different ways of doing the same thing. Using the FCU means no permanent live at lamp so can't use an emergency fitting. Depends if you think in future you may want to fit an emergency light.
But unless you have a 6A supply from your consumer unit/fuse box then you still need a FCU to reduce the maximum supply.
Where the lamp is to be hung off chains then often a ceiling rose is still used. There are special ceiling roses made by Click for example which allow you to plug in your lamp. In a garage being able to unplug the whole lamp and change it without switching off the rest of the lamps is very handy so that may be best option.
Also in a garage you may have problems with rotating machinery looking still when in motion with florescent lamps. Hence why grind stones often have tungsten lamp above them. Today the HF (Electronic) type of florescent lamp gets around this problem they also last longer and give out more light per watt used so are common in garages.
You don't say how big the garage is, what it is used for, or if commercial or domestic so there is no best option. Look in Projects
