I can't remember how long ago it was I thought of utilising a computer power supply to provide power to the the solder-less breadboard that I have, but sometime after that I realised that I could actually just utilise the power supply to provide power to the solder station fan(s) and lights as well.
I originally was going to modify an AC/DC adaptor with an AC power switch, so that I could completely shut off the unit when not in use (which is a vast majority of the time), but this idea makes that obsolete. At the moment, that AC/DC adaptor is what I'm using to power my soldering station fan and lights (with all the connections going through the breadboard).
Finding the parts wasn't too bad, after a while of searching, I stumbled upon the ATX motherboard specification, which gave me a start with the part numbers for the headers that I would need.
Eventually I found the specifications for the power supply and was able to more part numbers. Though, with the last post, I'm sure you were able to tell because of the harness I made.
I spent my 3-day weekend (3-5 September) scouring, comparing, cross-referencing all sorts of parts for the project... Needless to say, it wasn't the ideal way to spend the extended weekend, even though I had all the parts I would need.
I slowly draw the PCB patterns over the week after for all the parts I gathered, and once I had them all drawn, I placed them all in the board designer and ran into a huge roadblock - I don't have space for the all the parts within the limitations of the freeware version of eagle (100 x 80mm).
I set the project aside and began working on one of the stories I was needing to write. But recently I've returned to this project a bit.
I suppose before I continue on, I should outline a bit of the project itself.
The project will use 4 fans at minimum, but will allow me to expand that amount to 30. There will be two sets of lights (I just realised now that I didn't set up two lines for the lights), a bright set of lights (one or two of the 48-LED arrays from MPJA.com), and a set of "dim" lights, which is an LED light strip that I had used to replace the trunk light of my car with (because something broke the stock light housing and I didn't want it to just dangle around). There's also a blower fan as well, which I also haven't considered, but that shouldn't be too much of a problem.
The power to the fans are split into three lines, so that I don't exceed the amperage load of the wire and/or connectors, and have a fuse on each line which is cheaper/easier to replace than anything else, if anything were to happen (which I highly doubt). All the other power lines will have an appropriate fuse as well.
The power supply will connect to the main distribution board, and supply the power from there to the fan/light board and to the breadboard. There will be a set of switches to control the power from the power supply (PS-ON), and the mainboard will attach to a aluminium plate that will attach to two of the mounting holes of the power supply.
There will also be indication LEDs as well, most of which won't be entirely necessary. The switch to turn the power supply will have a bi-colour LED above it, so if the switch on the power supply (which cuts the AC power into the power supply) is on, then it shows one colour, and then if the power supply is turned on, then it shows the other colour.
This is done with the 5VSB line, which always provides 5 volts, as long as the power supply is receiving AC power. When the PS-ON line is shorted to ground, then the 12 volt line engages one of the relay coils to switch the colour of that indicator LED.
The fan switch for the soldering station fans controls 3 relays, since the switch I chose would not be able to handle 10 amperes by itself (a close calculated maximum because the fans require a bit more amperes when starting up - about 10% more). I realised just now that I actually did include a switch for the blower fan which is separate from the switch to soldering station fans.
The indicator lights for the soldering station fans will show that all the fuses are fine, so if one of the fuses blows, the corresponding light would turn off - to do this, there is another relay on the other side of the fuse. I think I also did the same with the blower fan and the soldering station light... I can't remember that well right now.
I originally planned having all sorts of power-input connectors on the board, but after a realisation late last week, I've taken some out.
I realised I never thought about the rating of the solder-less breadboard, and wasn't really able to find anything definitive. I think I set the limits at about 2-3 amperes, since I probably wouldn't be working outside of that... If I was working on the breadboard anyway.
Because of the realisations, I've lowered the 7 ampere fuses for the lines to the solder station fans to 4 amperes, since it would be better for the fuse to trip much sooner. The reason why I initially chose 7 amperes was so that it would blow before the connectors/wires/traces melt, but still allowing maximum current. Though either way works, it's probably better to use something closer to the maximum load of the line.
With that realisation, I was able to change the connectors to something smaller, so that i would be able to save space as well as keep it sensible. I scoured last Friday after work (23 September) for the new connectors, and ended up with the new parts that night.
Since I realised that I forgot about the "dim" light, I'll have to replace one of those parts, but it shouldn't be all too hard, since it's just the header and the plug housing.
It took a while to find the parts, since I needed something that would be above the new fuse rating, but also priced decently, since this project won't be cheap at all (the parts total is already over 100 USD, and the PCB will be around that price as well). I remember when I was initially looking for parts, that I stumbled upon some connectors by Hirose, but couldn't use them because I wouldn't have been able to crimp them. Obviously that has changed since I've purchased a sort of general-purpose crimper.
So the "output" connectors I'll be using are all from Hirose if I remember correctly, with one of them being shared with the soundcard switchboard project that I'll post about later. (I had gotten that connector for the switchboard first, and then copied it to this project)
Because I'll be mounting the PCB to the mounting plate, I had to use some through-hole switches and SMD LEDs. I'll also be utilising some light pipes for those LEDs as well, since the LEDs will be far from the plate. I decided on the SMD LED and light pipe combination, since it would make it much easier than trying to solder LEDs at the correct height to protrude or whatever from the mounting plate.
I've actually gotten some light pipes and standoffs in the project list, but those will be replaced accordingly once I get to that point.
The mounting plate will be made with 6061-T6 aluminium alloy, which will be machined, since it will be hell trying to do it all by hand and maintain accuracy/precision. I'm debating whether to get 1.6mm or 2mm thick, since the 1.6mm is cheaper overall, but the 2mm thick has a lower price per volume. I also had 1.6mm 6061-O6 alloy in consideration because it's cheaper than the other two, but I think I will stick with the 'T6 instead.
I'm still fairly certain that the board size limitation is still a major roadblock, and hopefully I can figure something out. I'm considering splitting the main board into two boards, but I'd rather not have to.
The board for the soldering station fans and lights will be separate, but should be fit within EAGLE's limitation quite easily, so I'm not all too worried about it. Now that I think about it, I might move the appropriate fuses to this board to save some space on the main board, and then I would have to move the fuse-monitor relay to the ground line from that board, which isn't that big of a deal.
I think this is all on the project for now. It'll cost quite a bit, but it'll be quite nice to have, since it'll allow me to utilise just about any power supply and be fairly future-proof (or at least I hope it to be).
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