Wiring CCFL Fan and BayBus Questions

dugn

dugn

Limp Gawd
Joined
Aug 16, 2009
Messages
398
I need help and advice that I haven't been able to find elsewhere.

In my Corsair Obsidian 800d case, I'm going to have 2 12" Cold Cathode tubes to accent the motherboard from the side and bottom. I'll also have 3 Logisys 120mm fans on the top with their circular cathodes beaming down from above.

All will be controlled by 3 blue LED Vandal (Lamptron) switches: Switch #1 - will control the 2 tubes, Switch #2 will control the 3 circular fan CCFLs, Switch #3 for later use.

Questions:

Where do I get 3V to run the LED in the switch. I understand the LEDs can only handle 3V, so where do I get a 3V line - or do I need to use resistors to ratchet a 5V line own to 3V?

How do I control the 3 Fan CCFLs with a single switch. How do I rig all 3 fan CCs to run off of a single switch since they all came with 1 switch apiece and 3 individual transformers?

Any other tips?
Since this is my first step into running anything non-standard in my new rig, I wanted to learn any tips or tricks needed to get this right. So far, the FAQs and guides I've seen just step you through installing Cathodes from a kit, or rigging a baybus, but not the details needed to rig 2-3 kits together and drive them off a single switch and step down the voltage to keep LEDs from burning out.

Any tips or instructional links would be greatly appreciated.
 
You can use a 3.3V line, with a small resistor to get it down to 3V depending on the tolerance of the LED.

To use a common switch you can tie all the grounds together at the switch.
 
Elledan said:
You can use a 3.3V line, with a small resistor to get it down to 3V depending on the tolerance of the LED.

To use a common switch you can tie all the grounds together at the switch.
Click to expand...

Thanks for the reply! I'll tie the grounds together then at the switch. Thanks!

Unfortunately, I'm still a little dumb on the 3V part. I know the molex connectors have 5V/12V leads, so do I pull 3V off the mobo or from some other source I'm missing?
 
As near as I can tell, those lamptron switches are momentary, which means the lights will only be on as long as you hold the switch down :p

To solve the 3V problem, you need to know the LED current @ 3V, which is provided (20mA). Calculate the resistance needed to be wired in series with each led using ohm's law: R = (V-3)/0.02, where V is the source voltage (likely 12V in this case so R = 450Ω -> use a standard value of 470Ω).

To have a momentary switch turn devices on/off, you can go one of four routes: design an rs-232/parallel/usb interface, use a flip-flop, find an already-made device for this, or use relays (two for each switch). Latching relays exist as well but you need to energize one coil to latch on, and energize the other coil to turn it off, so it's not of much use here...

Here's a link to the circuit you need to build for each switch (with relays): http://picasaweb.google.com/lh/phot...?authkey=Gv1sRgCLCTqMqR5NH0Cg&feat=directlink The two relays will provide a latched output, on or off for each press of the switch. Relay K1 only needs to be DPST, even though a DPDT is shown in the schematic (see Pole and throw). Relay K2 can be a small-signal relay, since it only needs to switch coil current and not the load. This configuration will not have memory - the lights will always be off when power is first applied to the circuit.
 
PM650 said:
As near as I can tell, those lamptron switches are momentary, which means the lights will only be on as long as you hold the switch down :p

To solve the 3V problem, you need to know the LED current @ 3V, which is provided (20mA). Calculate the resistance needed to be wired in series with each led using ohm's law: R = (V-3)/0.02, where V is the source voltage (likely 12V in this case so R = 450Ω -> use a standard value of 470Ω).

To have a momentary switch turn devices on/off, you can go one of four routes: design an rs-232/parallel/usb interface, use a flip-flop, find an already-made device for this, or use relays (two for each switch). Latching relays exist as well but you need to energize one coil to latch on, and energize the other coil to turn it off, so it's not of much use here...

Here's a link to the circuit you need to build for each switch (with relays): http://picasaweb.google.com/lh/phot...?authkey=Gv1sRgCLCTqMqR5NH0Cg&feat=directlink The two relays will provide a latched output, on or off for each press of the switch. Relay K1 only needs to be DPST, even though a DPDT is shown in the schematic (see Pole and throw). Relay K2 can be a small-signal relay, since it only needs to switch coil current and not the load. This configuration will not have memory - the lights will always be off when power is first applied to the circuit.
Click to expand...

This is exrememly helpful. The drawing helps immeasurably.

But I got the latching switches - so they stay in either the closed or open circuit position once pressed. I guess that changes the diagram a bit, eh?

This is exactly the help and insights I needed since I can now see exactly how I have to switch and set up resistance.
 
dugn said:
This is exrememly helpful. The drawing helps immeasurably.

But I got the latching switches - so they stay in either the closed or open circuit position once pressed. I guess that changes the diagram a bit, eh?

This is exactly the help and insights I needed since I can now see exactly how I have to switch and set up resistance.
Click to expand...

Doh :rolleyes: Well, glad at least some of it was useful.

One small note: calculate the power dissipated in the resistor to make sure it won't burn up - P = VI = (12-3)*0.02 = 0.18W, 1/4W resistor should be fine (any more than this and margin is low enough to require 1/2W imo).
 
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dugn said:
Unfortunately, I'm still a little dumb on the 3V part. I know the molex connectors have 5V/12V leads, so do I pull 3V off the mobo or from some other source I'm missing?
Click to expand...

You could get 3.3V from SATA connectors, for example. Look for the orange wires :)
 
PM650 said:
Doh :rolleyes: Well, glad at least some of it was useful.

One small note: calculate the power dissipated in the resistor to make sure it won't burn up - P = VI = (12-3)*0.02 = 0.18W, 1/4W resistor should be fine (any more than this and margin is low enough to require 1/2W imo).
Click to expand...

You could get 3.3V from SATA connectors, for example. Look for the orange wires
Click to expand...

Excellent. Very thankful for the help - and the detail of all the responses. It really helps me dive into this new modding area with some much-needed help. Thanks!
 
You're most welcome :) Let us know if you need more help/something blew up. Pics in the latter case, please ;)
 
Stumped on one thing - still need some clarification:

I looked at the SATA power specifications to find 3V - and the spec says it's there. But when I look at teh SATA power lines coming out of my PSU (Corsair 1000HX), I only see 5 wires - which makes me think I'm missing the 3V line. Especially confusing is that places sell 4-pin Molex to SATA converter cables that - for what I'm seeing - just take the 4-pin 5V and 12V lines and move them to a SATA connector - where I (again) don't see a 3V line to pull from.

I'm sleeving and assembling now, but I'm still stumped on where to get my 3V (or 3.3V to step down) power for the CCFLs...

Any help?
 
or you could just use the standard power for IED devices and just tap off of the +5V rail and not be tapping into a more sensitive rails that provide power to the CPU or ram controllers........:rolleyes:

if memory serves me correctly with the logisys ccfl fans... each power converter box should be able to handle two ccfl..... also the power switch for the ccfl lights can be desoldered from one switch and added to another.... just make sure you don't exceed the current rating on the switch.:cool:
 
The 5V rail isn't the issue. I'm stepping 12V down using appropriate resistors, even though I could have just as easily used 5V with different resistors. Remember, this is for the 3.0 (not even 3.3V) LEDs - not the CCFLs. The CCFLs are running right off of a 12V line directly.
 
dugn said:
The 5V rail isn't the issue. I'm stepping 12V down using appropriate resistors, even though I could have just as easily used 5V with different resistors. Remember, this is for the 3.0 (not even 3.3V) LEDs - not the CCFLs. The CCFLs are running right off of a 12V line directly.
Click to expand...

we would like to see a pic when you are done as this build sounds interesting...:cool:
 
Most of these are spread throughout the Corsair Obsidian thread - and I'm still in the process of wiring the baybus (and I'm not electronically inclined).

Here are the best pictures consolidated for this still-in-progress build. The completed items are:
  • All PCI backplanes powder black coated and re-installed on cards
  • EVGA GTX 275's modded from red to white
  • All cables either sleeved (the small ones) or black vinyl dyed (the 20/24 pin and the PCIe)
  • White CCFL fans mounted (above)

Remaining work
  • Wiring and testing baybus to control all lighting from 3x 22mm latching Vandal switches (white ring LED to match the Corsair white power and HDD LEDs) into a 5 1/4" bay
  • Add 2x 12" tube CCFLs (below) with black shield to reduce their brightness and direct the light into the case
  • Cleaning up the rat's nest of cable routing in the back

dsc01015medium.jpg


dsc01011medium.jpg


Before the black dye

dsc01078medium.jpg


Close-up of the white modded cards

dsc01097medium.jpg


Dyed black cables and better shot of the whole thing

dsc01094medium.jpg
 
dugn said:
Stumped on one thing - still need some clarification:

I looked at the SATA power specifications to find 3V - and the spec says it's there. But when I look at teh SATA power lines coming out of my PSU (Corsair 1000HX), I only see 5 wires - which makes me think I'm missing the 3V line. Especially confusing is that places sell 4-pin Molex to SATA converter cables that - for what I'm seeing - just take the 4-pin 5V and 12V lines and move them to a SATA connector - where I (again) don't see a 3V line to pull from.
Click to expand...

The SATA standard has 3.3V but it's not widely used. Since IDE-SATA power adapters would most likely become fairly popular and a lot of early SATA drives were actually converted IDE drives, they didn't need 3.3V and didn't want to rely on it too much (since the adapters had no easy way to provide it).

Actually, that's right in the Wikipedia link at the bottom of the section...
Adapters exist which can convert a 4-pin Molex connector to a SATA power connector. However, because the 4-pin Molex connectors do not provide 3.3 V power, these adapters provide only 5 V and 12 V power and leave the 3.3 V lines unconnected. This precludes the use of such adapters with drives that require 3.3 V power. Understanding this, drive manufacturers have largely left the 3.3 V power lines unused.
Click to expand...
 
InvisiBill said:
The SATA standard has 3.3V but it's not widely used. Since IDE-SATA power adapters would most likely become fairly popular and a lot of early SATA drives were actually converted IDE drives, they didn't need 3.3V and didn't want to rely on it too much (since the adapters had no easy way to provide it).

Actually, that's right in the Wikipedia link at the bottom of the section...
Click to expand...

Thanks for the assist InvisiBill. I got frustrated at trying to pull a reliable 3.3V line from a SATA connector that I decided to use the more pervasive and prevelant 12V lines all ov er the place. It worked out well since I ended up learning enough about electricity to know how to step these down and which resistors to do it.

So, I'm effectively stepping down 3 12V lines to 3V for each of the 3 switch-based LEDs.
  1. Switch one consolidates 3 switches for CCFLs at the top of the case
  2. Switch two simply replaces a single switch for 2 12" CCFLs at the bottom of the case
  3. Switch three will be wired to nothing (future use) but will have the 3V LED like the others for on/off visual response

I'm a few days away still, but once I wire this up, I'll take some pix and post them here.
 
One could use 1 12V line as well for 3 3V LEDs. Seems easier to wire to me if there's enough Amps on the 12V line, plus it produces less heat (resistance-based step-down, switching PS would be more efficient. And complex).
 
Elledan said:
One could use 1 12V line as well for 3 3V LEDs. Seems easier to wire to me if there's enough Amps on the 12V line, plus it produces less heat (resistance-based step-down, switching PS would be more efficient. And complex).
Click to expand...

Agreed. I'm still learning. So if I feel comfortable doing it that way (a few more calculations), then that's how I'll do it. stepping everything off of a single 12V and powering all 3 LEDs is the way to go. I just need to map it out to be sure I get it right.

Thanks for the encouragement, help and insights.
 
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this reminds me that i will be starting several math threads where i will explain how the math works and answer questions.....
 
thaltek said:
this reminds me that i will be starting several math threads where i will explain how the math works and answer questions.....
Click to expand...

Please ping/PM me when you do. I'd love to latch on and learn + validate what I've picked up so far...
 
tommorow i hope to expand on resistors, capacitors, and inductors...... which reminds me that i have been thinking about setting up a board in the front part of my clear case with vacuum tubes and have them illuminated from underneath....
 
Sounds good. I'll watch for it...and for pix of your upcoming creation...
 
i will keep you aprized but the project won't move into action until i get some uni work done and get about 20 other projects wrapped up....
 
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