LED Lighting

Are you running Express / Expression? What LED fixture are you using? When you say the LED is 8-bts, do you mean it is an 8-Channel LED?

Regarding your DMX: please confirm you have a 1-In 5-out opto-splitter? (a box of some kind that is splitting the DMS line)

Yes, each of the 512 addresses in a DMX universe is being sent a value consisting of 8 bits. If you understand binary, you will know why the maximum and minimum values are 255 and 0 respectively. When you enter a percentage intensity into the command line, the console is really outputting its binary equivalent, not a value between 1 and 100.

For instance:
0% is 0
50% is 127
100% is 255

Thanks Aaron. So if I wanted to send decimal 128 to me gizmo - I'd put it at 50% on the board(I.E. 50% of 255 - devices max)

Running Expression 3. Using a dirt cheap 'DualFire 18 LED Par Light'. "B bits" refers to the DMX512 data bits sent to the device with the appropriate address (DIM#) on that universe. My cheapo is a 7 channel device (takes up 7 CH on board). Each CH can take a values of 0-255 or a sub range within that. Ref the splitter. Yes - it is a professionally installed splitter.

That's exactly right. Many theatrical lighting desks adopted the percentage format back in the day as it was more intuitive for setting intensities on dimmers, as opposed to entering 64 for a quarter of fixture's full brightness.

Yeah, I think he was asking about the splitter because the way you described it made it sound like a splitter cable — something you never want to use in DMX chains.

Oh heavens forbid! I traced my neighbor poor TV reception to a spliced TV cable! His reply to my gasp of horror was "Well, I wanted to run two TV's!" Being deeply into digital comms (W4JPA) I actually had nightmares of his SWR ratio visiting me at night.

As soon as the theatre quietens down I'm going to sneak in with the LED and try it out. I know the book goes on about "Personalities" but I'm pretty sure for starters I can merely address the 1st and subsequent CH#'s, fire some numbers & to watch the action.

If desired, you could build a fixture personality for it in the offline editor.

Now that's a good idea. I bought a USB 3.5" floppy drive to be able to Tx stuff but the wretched thing didn't work and I sent it back. I'll download that program tonight. Just hung a couple more spots and having my lunch using a back stage amplifier to blast out my music. Being totally alone in a theatre is kinda cool.

Well - I got Freestyler and built a profile for this cheapo LED and had the thing up'n running at home in no time. Great DMX lesson. But alas the trip to the theatre with it was a bust. We have 3 universes leaving the board although we only connect to a single SENSOR 48 Dimmer rack. An outlet on the wall says DMX Port 2 but looks like it's "Y" 'd (Optically isolated) to the 1st universe. But setting dimmers and channels to say 128 and my gizmo to 121 then sending 50% to CH 6 and 7 (which worked fine in Freestyle) didn't do a thing! I would give my eye teeth to know who/how this wiring was run.

And really weird; On the console, I can set # of dimmers to say 1536 (512 x 3) fine but can ONLY set # of CH's to < 400 ! My idea was to use an address > 512 to see if that outlet really was in the 2nd universe. I thought I was getting pretty good at this stuff but now stalled. Pity because I wanted to buy a couple more LED's for some special effects in "Joseph and the . . . . coat" coming up. Thinking cap time.

Email me your venues name and full address and I’ll see if I can find the wiring diagrams for how the DMX was (at least) originally wired. mmeskill@etcconnect.com

Based on the submittal / field service drawings (I need to find the ‘as built to confirm):
3 DMX inputs in the Booth.
DMX 1 to the Sensor Rack
DMX 2 to the Stage on a plate with RFU
DMX 3 to the House
Based on this, DMX 2 from the board should be wired directly to the DMX 2 output on the stage. Try to remove any external splitter and plug directly to the Output and see if that works.
Also, I was a little unclear on your addressing. DMX Port 2 from the board would be dimmer 513 in patch; DMX 3 output would be dimmer 1025 in patch; Soooo Dimmer 513 will output from Port 2 as DMX 1. Try patching dimmer 513 to channel 101; 514 to channel 102; 515 to channel 103 and so on for the number of channels your fixtures needs. On the fixture end set your DMX start address to 1.