Sparky help

[VWD]

Attached circuit is my understanding of a Fluorescent ( not a flour one as I spelt it, so no Dough Jokes, please). That's for one either 8W or 15W tube. I'm struggling to make some PCB( that printed circuit boards ) using the iron method ,but professional light boxes cost an arm and a leg, and I need both my arms and my remaining good leg to walk ( well hobble on ) ,so as the most expensive bits are the tubes, I'll make my own.

Problem is -do/can I use a single starter /and or ballast ( AFAIK starters have no power problems, but ballast do) , or do I have to use one of each for each tube.

 

 

[GentleGiant]

Have you considered LED strip lights?? A lot less complicated, less power and probably last a lot longer.

 

And the box will be a lot lighter.

[StevesTruck]

You can get standard length fittings dirt cheap if you go to an electrical factors. Why not just get one and strip the bits you need out?

[Warrior193]

Hi VWD, from your circuit I assume that you are looking at "iron" ballasts (choke) rather than electronic - is that correct? I would second the suggestion to have a look at the LED option.

You will get a lot of flicker with the switch-start set up, if the LED option looks too expensive for you, why not consider high frequency electronic ballasts and slimline T5 tubes, there are a number of adaptable types of these ballasts out there. SS is so inefficient now. From memory, as it is ages since I have even seen one of these, you will require one starter switch per tube - but depending on the ballast, it is possible to run more than one tube (usually T8) on it. Go for the electronic T5 or the LEDs. 

Warrior193. 

[VWD]

You can get standard length fittings dirt cheap if you go to an electrical factors. Why not just get one and strip the bits you need out?

Steve- that was my idea, but I'd prefer to compare a diagram to my finished article. GG- Further research points me that way , IF I can get the correct FREQUENCY led strips at a decent price.

but years ago ,i started building one ,got as far as the box ,with glass & a lid and one tube, then got hit with redundancy and a forced home move, so lost interest.

[Coops]

I have some LED tubes at work doing nothing if you need them.

[GentleGiant]

Steve- that was my idea, but I'd prefer to compare a diagram to my finished article. GG- Further research points me that way , IF I can get the correct FREQUENCY led strips at a decent price.

but years ago ,i started building one ,got as far as the box ,with glass & a lid and one tube, then got hit with redundancy and a forced home move, so lost interest.

 

Also consider LED undercounter/trim lights on a flexible strip; I got some from Lidl 2 Christmas' ago and they were eye seeringly bright; about 3-5m in length in think they were (not got the decorations out yet).

 

Frequency or temperature?? LEDs are usually run on DC, so there shouldnt be any 50hz flicker, the shade of white is referenced by the colour temperature. 4000K, 6000K etc. But you already knew that.

[VWD]

Wave length of the EMITTED LIGHT is the crucial factor, to produce the desired effect on the photo resist on the PCB, and the light from a UV-A tube is harmful to eyesight.  Pro boxes cost upwards of about £150 or so , but the tubes & starters cost less than £20 , from RS, whose data sheet ( http://docs-europe.electrocomponents.com/webdocs/002c/0900766b8002c6dd.pdf) gives me the data for the ballasts in series and parallel . All I've got to find out now is the optimum distance between centres for the tubes and optimum distance tube to board .

i've already got a box designed for a 12" 8Wtube , so for little outlay ( tubes plus  either one or two cheapo 8W fittings, I'd have a light box ( or to give it it's Sunday title -UV Exposure unit for making PCB) for at the most around £30 .

Ironically, I could easily overcome the need for a ballast to drop the current once the tube has struck , by dropping the mains to something like 24v and inverting it up at HF via an IC & step up transformer , with current sensing to drop the inverter output voltage once the tube had struck. But like the song about the hole in the bucket- I'm having problems making PCB this weather .

[GentleGiant]

AHH! Sorry, when you were talking light box, I was thinking photography, not pcb design and masking.

[VWD]

Thought that GG. For photo /etc, I'd pop down to world of £ and get some low wattage LED LAMPS. But for this I've jumped into the deep end of the Fluorescent pool. Think I've got it sorted now . RS do the tubes/starters as a kit of two 8W and also a ballast ( electromagnetic ?????) and also a diagram to connect things up. If anyone can advise, it's RS 793-4679,

and connection 3 that I think will do the job .uNLESS ANYONE KNOWS DIFFERENT AND CAN ADVISE .

[GentleGiant]

You can get UV LED bulbs, but last time I looked, they were not cheap.

 

Mind you, I cant remember when blue LEDs were £12 each.

[Updown789]

Tridonic do a hf 8w ballast if you are looking to avoid 50hz flicker. Tridonic pc 1x8w basic Art no.22176026 if this is any use. No starter needed as it's HF

[GentleGiant]

You can get UV LED bulbs, but last time I looked, they were not cheap.

 

Mind you, I cant remember when blue LEDs were £12 each.

 

OOOP,s meant to say CAN remember.

(Its been a bad few days)

[VWD]

Tridonic do a hf 8w ballast if you are looking to avoid 50hz flicker. Tridonic pc 1x8w basic Art no.22176026 if this is any use. No starter needed as it's HF

Spotted that one, but i've got an RS about a mile from me , so no waiting time or carriage.