by ericmark »
Sat Aug 01, 2015 8:35 am
Can it be done yes.
However how is another question.
To start low voltage = 50 ~ 1000 volt AC so I would assume you mean extra low voltage which is up to 50 volt AC?
You today rarely get simple transformers they may be called electronic transformers but in real terms they are switched mode power supplies often these have a range of wattage 50 ~ 150W is quite common.
You have not said if you supplied each light with a single transformer or one transformer each? But there is what is refereed to as inrush with standard transformers which can be 10x the normal current used. So a 10A switch can often only supply 100W of transformers, but maybe 500W of electronic transformers (switched mode power supplies).
Today extra low voltage is only really used in the bathroom many people are ripping out their transformers because of the problems using CFL and LED lamps.
In the UK the tungsten lamp worked well, in the summer our rooms are not that warm at night so the radiated heat from the tungsten bulb is not a problem and in winter they work very well as one can set the central heating to 18 degrees C and in the evening the radiated heat makes this feel like 20 degrees C so no need for electronic thermostatic radiator valves to adjust the room temperature day and evening. As a result we were slow to move to lights which did not give out heat.
In the rest of Europe the heat from the lamps was a problem so they moved much earlier than us. As a result they wired their houses 1/3 and 2/3 to two switches giving three levels of light no dimmers required and used hot air central heating so all rooms the same temperature they do not have the option to have each room temperature set according to it's use. So one central thermostat which can be programmed to raise the temperature in the evenings.
However the politicians seem not to realise we use different systems to rest of EU and started a campaign of getting rid of bulbs which both lit and heated our rooms.
So we have to change our simple TRV for electronic versions which can be programmed to alter the temperature at different times of day. This works well with the old boilers but where the boiler have condensating technology then the electronic TRV upsets the anti-cycle software of the boiler.
So back to lights. What we have to decide is if we still want tungsten lamps? Or for how long we want tungsten? In the main LED lamps are better running from our low voltage (230vac) supply direct. Where with tungsten lamps specially those using quartz using a regulated extra low voltage supply (12vac) makes the lamps last longer as long as no silly dimming switch is used. (quartz lamps should not be dimmed)
Distributing the low voltage (230vac) rather than the extra low voltage (12vac) means it is easy to swap between lamp types. The 2" (50mm) spot lamps using GU10 bayonet fitting can be swapped between tungsten, cold cathode, and LED by simply swapping the bulb. But the extra low voltage type often need the electronic transformers swapping to convert to LED and can't use cold cathode lamps.
Since you don't say if 230v or 12v is distributed can't say how you would add the extra two lamps. But it can be done. I would distribute the 230v personally with if using extra low voltage bulbs a dropper for each bulb.