Anyone remember Chroma Q Color Block Cable

lilricky

Active Member
I'm trying to hook up a set of DB4 Color Blocks. The short little cables that came with them has a pair of 22 ga wires and a pair of 14ga wires. If you can recall, how critical is that configuration? I found some shielded 16/4 here locally, but not that odd configuration. I did find a place online but they were really proud of it.
Thanks
 
I'm trying to hook up a set of DB4 Color Blocks. The short little cables that came with them has a pair of 22 ga wires and a pair of 14ga wires. If you can recall, how critical is that configuration? I found some shielded 16/4 here locally, but not that odd configuration. I did find a place online but they were really proud of it.
Thanks
@lilricky I have ZERO personal familiarity with your units but while you're waiting for a more knowledgeable poster I'll offer a few thoughts. I strongly suspect you're going to find the following: The 16 gauge pair likely conduct power and are most likely twisted as a separate pair. The 22 gauge pair most likely carry data. The two pairs will be individually twisted, possibly in different directions and / or different number of twists per foot to minimize cross-talk. Are either of the pairs shielded? If so, the shield would most likely enclose the smaller 22 gauge data pair, again to minimize coupling / cross-talk. If there is a shield it may be connected at one or both ends and most likely to whichever contact offers the lowest impedance path to ground and / or a metallic enclosure.
There you go Sir! My best pure guesstimates gratis and worth every penny I've charged.
Further thoughts: How long are the cables you have? How long are the cables you're hoping to fabricate? Twice as long or twenty times as long?? Do you have enough of your short cables to couple them together and test the longer length you're hoping to acquire? How expensive is the 16 / 4 cable with overall shield you've located locally? Are you able to purchase only the length you need or is it only available to you in 1,000' put-ups? Can you source the connectors you'd require to fabricate the longer cables you desire? How badly do you want your longer cables? How much do you value your time?
I suspect you see where I'm going. How much have you got to lose by making a cable, metering it carefully for correct connections, pin-outs and absence of any unintended shorts and giving it a go?
One last thought from my past for you.
Back in the early 1990's I was playing IA Head Electrician for a scenery and automation shop fabricating custom scenery for Canada, Broadway, London England's West End and even one opera set for Red China. Our shop provided the first automated AC Servo drives on Broadway when all the other shops were still doing DC drives.
Here's the pertinent part of this novella:
The manufacturer of the motors, resolvers and motor-drives we were using were more accustomed to controlling precision turret lathes and similar automated machinery often associated with CNC routers and automobile assembly lines. Based on their experiences in those environments they were recommending maximum cable lengths of 15 to 20 feet between their ACservo motors with their internal resolvers and their drive electronics. In their user manual they suggested contact the factory prior to considering any interconnecting cables longer than 25 feet.
The factory laughed A LOT when we contacted them asking about 50 foot cable lengths. This was for our first application in Toronto.
We worked with our dealer, fabricated our own 50 foot cables and perceived ZERO problems.
(There is a considerable difference in repeatably precise positioning required for a precision turret lathe machining automotive crankshafts and a system positioning theatrical scenery across a 50 or 60 foot proscenium.)
Over the course of approximately 100 automated AC servo drives in a dozen or so productions we'd extended our custom cables to 100' for many of the 24-ish automated AC servos in the first production our shop built of The Who's rock opera "Tommy". When we landed the contract to build "Tommy" again for Offenbach / Frankfurt, Germany in 1995 we visited the venue then headed home to fabricate our first 150' cables. One year later we were building all of "Tommy" AGAIN this time for London's West End, I believe "The Shaftesbury" was the theatre. My memory's getting a little hazy on the name of the theatre but I definitely remember having to fabricate 200' cables for the venue, back stage was tiny but we had drives everywhere from barely below grid level to down in the basement trap room below SL but all of our drive racks were stacked and clustered on a small mezzanine high above stage level on SR. Don't ask me to remember if SR is PS or OP (Prompt Side or Opposite Prompt) as we had to pre-label everything prior to shipping to England.
Our AC servo drive dealer was impressed and the manufacturers were incredulous but we kept on buying their drives, rarely ever requiring factory service and generally being happy campers.
Getting back to one of my theories for successfully making ever longer cables.
We were purchasing our raw cables wholesale, usually in 1,000 foot lengths and often in 5,000 foot lengths.
Every time the owner of our company'd get a lead on a new production and ask if I thought we could do cables of an even longer length, I'd neatly and correctly install connectors on the free end of a reel, spool off a length twice as long as our owner anticipated needing, chop the cable and temporarily add connectors to this double length, connect a servo motor and resolver to its drive electronics and see if, how well, it worked.
- If it worked flawlessly GREAT!
- If there was the slightest hint of a problem, I'd chop the cable in half down to the length the owner was requesting and test again. By using this approach our cables successfully got ever longer and longer until we were shipping 200' cables to Great Britain with complete confidence and zero loss of sleep.
Back to my point @lilricky What have you got to lose by trying?
Epilogue: The cables connecting most of our motors to their drives were stranded 12 gauge spiral twisted 4 conductors with an overall foil shield and stranded drain wire to minimize radiation of the drive's bridge power from escaping too far and annoying the sound lads with their wireless mics and keep our drives from bothering the pick-ups on the electric guitars.
The cables linking our resolvers to their drive electronics were a smaller gauge but again stranded and with an overall foil shield to minimize the intrusion of the sound lads' RF and lighting dimmer hash into the sensitive positioning input of each drive's drive electronics.
In addition to our bridge power and resolver cables, each automated axis also had a cable for a DC operated mechanical brake which was energized to release and de-energized to apply the brake. Normally the drives maintained their positions but the brake was de-energized and applied whenever the drives were being shut down and / or the E-stop applied. Experience taught us that gravity isn't your friend if you power down an AC servo while it's supporting several hundred pounds of scenery high overhead. The DC brake cable was another stranded twisted foil-shielded pair, this time to suppress radiation each time the brake was applied and the sudden collapse of the brake's magnetic field resulted in an intense spike similar to your grandfather's Ford model T's ignition coil. Of course we had suppression diodes across all of the DC brake coils as well for good measure.
Each automated axis also had a fourth cable which was normally four conductors, a common and one conductor for each of three mechanically operated rotary "hard" limit switches, one for each absolute end of travel and the last to provide an accurately repeatable homing reference location.
There you go @lilricky More than you NEVER wanted to know about automated AC servo drives and their associated control cables. All the best with your longer cables.
Toodleoo!
Ron Hebbard
 
These sounds like relatively standard 4 pin XLR cables. Standard is a bit of a taboo, because the pinout does vary between manufacturers of where the power and data lines land in connector. Call around to your local shops and see if they have scroller cable, or similar. Be *very* careful to check the pinout. I know I've got a bin of the stuff on a dusty backshelf since we don't run any of that equipment any more.
 
From the manual:
The Color Block utilises an XLR 4-pin cable system. This is used to supply power and control data. Pin 1 = 0VDC, pin 2 = control minus, pin 3 = control plus, pin 4 = +48VDC. The chassis should be ground bonded.
Only genuine Tourflex Datasafe cable is recommended for use with the Color Block system. Damage will occur if power connections short-circuit to data or ground shield connections. When assembling XLR4-pin cables, heat shrink should be used on each individual data pin and the drain wire to prevent short circuits.
The Color Block power supplies deliver power and data via XLR4. A maximum of five daisy-chained Color Block DB4 fixtures can be connected to one cable. Return lines are not required. The total cable length of each chain must not exceed 60 meters (200ft). It is recommended that a maximum 20m XLR4 cable length separates adjacent units as this can cause signal deterioration.

See also the thread https://www.controlbooth.com/threads/4-pin-scroller-cable-rules.20437/#post-184286 . Your 16/4 MAY work, IF the distance is short and not trying to daisy-chain many units.
 
Indeed all above for short distance, but than back to the rules. Scroller cable preferred with above notes. Such cable is still sold by say TMB, Lex, and many others. Recently did a quick job requiring scroller cable connections like yours. Took some 20 year old scroller cable and cut it up for the needs. Worst cable ever in oxidized in soldered... Just too old in later trying to connect in a new length. Something to keep in mind for re-purposing old cable. But certainly the voltage conductors are there for a purpose, as with the shielded from power data. Should follow that rule unless a very short length.
 
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I can't think of any reason why you couldn't substitute two-pair 16/4 for the cable you have, electrically, as long as any shielding necessities are observed. Now, that itself might be troublesome.

Short version: are they proud enough of it to make your investment of potential remake time worthwhile?

They call it 'gambling' because sometimes you lose...
 

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