Your "question" probably has most of the information required to 'get going' BUT it is very hard to read. Some people have trouble extracting questions out of such a complicated mixture and may vote to close the question rather than trying to understand it. Making the actual questions as clear as possible will help others to help you.
Can a pulse width modulator share the same return neutral
Yes, you can have a singe common conductor. This needs to be of low enough resistance that current changes from one colour do not produce so much change in voltage drop in the neutral lead that it affects the voltages that the other colours "see".
A particular smd led i was looking at seems to be a straight forward connection 6 terminals three at either side you would simply bridge three at one end connect them to positive and the three at the other end to neutral and you would do this for each colour
You need to look at the data sheet or see how they are connected internally by testing. In many cases such arrangements are indeed 3 independent LEDs and you can parallel them by connecting all the pins on a side together, as you suggested.
While ideally you DO need a resistor for each LED in such an arrangement, in practice the 3 LEDs within a single package are closely matched and may be "hard paralleled" without too much imbalance. Note that LDDs in different packages are NOT likely to be well matched and each group of 3 LEDs in the one package usually needs a resistor.
And do i need resistors for these as the website doesn't state.
You say "the website" -> please provide as much information as possible including links to datasheets and associated material. See above re needing resistors.
I originally looked at RGB smd led's but they share the same active and separate return neutrals in which case a PWM would not work as it needs to interrupt the supply to the led's.
You can probably find tricolour LEDs with common Cathode if you look for them.
and i guess my final question is would this work if the 1st two are a yes?
You seem to be describing using 3 strings of coloured LEDs, all LEDs in a string parallel connected and each LED or group of 3 in pkg having its own resistor.
So - YES such an arrangement would work if done properly.
If it would work is there an easier way to achieve the same task?
What can be easier. The system you describe is very simple. You could use linear feed but that would be less energy efficient.
I originally wanted to use a DJ styled sliding switch to modulate the intensity of each colour individually (one switch for each colour) and use premade clusters that i could wire up a supply to each colour red, green and blue. However after learning the active is shared that wont work.
As above. Find common Cathode RGB LEDS if you wish to have them combined.
However - you can but RGB LED strips - usually designed for 12V operation. These are liable to cost less per LED than a system that you build yourself.
Im kinda stuck I hope the message of what im trying to achieve gets across? Basically 240v a.c supplying my driveway and foot path lighting in which I can control the level (brightness) of green, red and blue individually whilst still maintaining this system to be as reliable as possible. (and the main aim of making a system I would like to buy or make which ever is necessary extra led cluster or which ever configuration i end up with so in the long run should one blow I can simply replace it, also should one blow it will not effect the rest of the circuit that being the reason its all in parallel.
More soon ...
Most light bulbs have a number of service hours designed in. This is achieved fairly accurately and on purpose during manufacturing. Consumer grade light bulbs burn out faster and the awful truth is that in that way the manufacturer ensures it can keep producing the light bulbs and make money. The main cause is the tungsten filament slowly evaporating until it gets too thin to carry the current. The trick during manufacturing is to etch the filament to a carefully designed thickness so the lifetime is reduced programmed.
The origins of programmed life light bulbs began with the Phoebus Cartel in 1924.
There are also light bulbs with a special stronger filament (basically they skip the 'etch-cycle'), these are for use in high reliable applications and last longer. They are commonly used in places that are hard to reach and are more expensive. Not sure about the proper name of these light bulbs. Because of the extended life time these bulbs are more expensive as a manufacturer has only limited room for producing spares. (What need is there for spares if the bulb doesn't fail?)
Where Australia and EU banned the consumer grade bulbs, the strengthened filament is not banned because of its specialized application. The latter type is just not available in your regular shop around the corner.
Best Answer
****WARNING: The tube drivers decsribed below make a very higher voltage to operate the tube. Hundreds of volts is typical. Over 1000V occurs on large CCFL units.
You can get a serious electric shock from these.**
I assume that you mean CCFLs "Cold Cathode Fluorescent Lights".
Like these -
IF they ran from the 12V from a SATA power plug you can run then from 12V. If so they will have had a controller which must be used with them. The controller converts the 12V to a higher voltage.
They may have run from the STA 5V supply - less likely. You need to connect to a SATA power supply socket and measure which voltages appear where ON THE INPUT TO THE CONTROLLER FROM THE SATA SOCKET. Do NOT try and measure the output voltages from the controller. Cheaper meters may emit magic smoke and meter users in some cases may emit magic smoke as well.
Useful CCFL page
CCFL driver IC datasheet - UCC3973 etc - shows what's involved. You do NOT want to build one of there. Commercial units are cheapish.