EL Wire SCSI cable

[olePigeon]

I was wondering.  Is there enough power on a SCSI cable that if you used an EL Wire it'd glow?  I've seen SCSI terminators that light up an LED.  Would be cool if the termination wire was an EL Wire instead... glowing when you terminate a SCSI chain.

 

[bibilit]

I have got one of those, will make a picture if you want, enough LEDs on it that will make a christmas tree feel ashamed.

 

[olePigeon]

Sure.

I have an el wire at home.  I wonder if it'd work.  Suppose I can just try it.  I don't quite understand the SCSI cable layout, anyone here hazard a guess which wire I'd use?  Presumably the termination wire... or whichever two wires would be used to make an LED light up.

 

[Gorgonops]

So... it looks to me like EL wire requires an inverter to supply a high-frequency (and relatively high voltage at around 90v) current to it to glow. A small inverter capable of driving 1-8 feet of wire draws about 200ma @ three volts. In theory then, yes, I suppose you could drive that off the TERMPOWER line on a SCSI chain, as TERMPOWER is per standard supposed to be able to supply about one amp at five volts. (Although there are different figures for this; one source said 900ma, another said up to 2A, and there are also considerations related to voltage drop over long cable runs.)

Practically speaking, though, it sounds like a sort of crummy idea. It would probably be safer to tap your 5v more directly off, say, a SCSI enclosure's power supply and drive your blinkenlights indepenantly. A typical LED like you might find in a light-up external terminator only pulls about 20ma; that's a tenth of what an EL cable run will draw and I'd also worry a little about a cheap little inverter putting noise on the data lines if you pull from TERMPOWER.

 

[olePigeon]

El Wire power cables already exist.  I guess the actual SCSI cable itself would be problematic.  I was thinking maybe El Wire would be similar to a regular LED, but I suppose not.

 

[Gorgonops]

El Wire power cables already exist.

Are you talking about cables to power an inverter off a computer power supply, or a power cable that has EL wire in it?

In any case, EL wire has pretty much nothing to do with LEDs. It has more in common with a florescent light bulb.

 

[olePigeon]

A power cable that has an EL wire in it.  I was thinking of doing the same with a SCSI cable.

 

[Gorgonops]

I'm sure that power cable has the power supply for the EL wire embedded in the plug housing.

Really, if you want to make a SCSI cable like that there's nothing stopping you, assuming you can find or make a 20-something conductor cable with a clear outer insulation you can thread the EL wire into. I'm just skeptical that driving the inverter with termpower is a great idea. There are plenty of other places you can tap 5v or 12v in a chain of SCSI enclosures.

 

[olePigeon]

Could just piggyback it on the power cable.  Meh.  It was a neat idea in my head, just isn't practical in the way I wanna do it.

 

[bibilit]

Sure.

Here is my SCSI Bus tester...



As i said a lot of LEDS...

 

[olePigeon]

Very cool.