Quality DMX Cable? (and Pin Connectors)

gafftaper

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Putting together the sealed bid specifications for my lighting package. What brands should I consider "acceptable" for DMX and Scroller Cable?

Lex is the only one I know for sure. Who else?


OH!! Also what brands should I list as acceptable for Cheeseborroughs so I don't end up with a bunch chinese stuff?


OH OH... what about GSP Connectors... Anything I should specify there besides clear cover?
 
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Putting together the sealed bid specifications for my lighting package. What brands should I consider "acceptable" for DMX and Scroller Cable?
Lex is the only one I know for sure. Who else?

Belden makes some great cable, cant rememeber the DMX cable off the top of my head. Tourflex is also some really rugged stuff.
 
Belden, and I can't remember the exact number, is usually THE cable spec'd in the DMX protocol. I beleive it used to be Belden 5143 but don't quote me.
http://www.belden.com/pdfs/Techpprs/DMX-512.pdf
Here's an interesting link to the Belden website. has tables for suggested belden DMX cables as well as a discussion on the "proper" Belden ethernet cable to use.

clamps, http://www.clampsunlimited.net/products.htm#Double-Right_Angle_Coupler I can't guarantee that their not from china, but, all their clamps are rated and you can D/L the testing certificates from the website.

GSP's, I don't know about everyone else, but I hate the new "ferrule" type. I've had really bad experiences with this type of connector. I'd much rather be forced to install crimp connectors, than run the risk of shearing all wire strands with the ferrule getting crimped to hard.
 
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GSP's, I don't know about everyone else, but I hate the new "ferrule" type. I've had really bad experiences with this type of connector. I'd much rather be forced to install crimp connectors, than run the risk of shearing all wire strands with the ferrule getting crimped to hard.

Hmm... now I'm glad I asked. I was just wondering what brand to specify... I know Union Connector but that's it. Anyway, I see I have the option of "pressure plate" or "Crimp Lug"... I didn't know I had an option. I've always used the one where you crimp on a spade connector and screw it down... I guess that's "pressure plate". Am I right? Does anybody think the "crimp lug" style is a good idea?
 
I am so glad that we really only have one choice to make in this country. Do we buy Clipsal or the cheap knock off.
 
I am so glad that we really only have one choice to make in this country. Do we buy Clipsal or the cheap knock off.

You wouldn't believe my list. I'm at a state college and so because this equipment is going to be over $46,000 it has to go through a public sealed bid process. Because of that I have to have a specific manufacturer and model number for every single item. If I don't, someone will undercut the legitimate dealers with Chinese cheeseboroughs and some junk DMX cable... win the bid... and I have to buy from them because it is the lowest priced product. It's insane!
 
Belden 9842 or 9156, or equiv. A Google of "Belden DMX cable" is useful

There was recently a thread on the stagecraft list about this, where the current suggestion for in-conduit installation is to use Cat5e cabling for DMX. This is acceptable as per USITT standard and is somewhat cheaper then using the heavier jacketed Belden type cable. The recommendation is to limit any Cat5e cable used for DMX to 300ft. runs max., in the event the cable is later converted to ethernet use.

The recommendations is to use the Belden cables for all open-air usage, though heavier guage Cat6 (?) cable works well for DMX applications as well.

SB
 
it has to go through a public sealed bid process. Because of that I have to have a specific manufacturer and model number for every single item. If I don't, someone will undercut the legitimate dealers with Chinese cheeseboroughs and some junk DMX cable... win the bid... and I have to buy from them because it is the lowest priced product. It's insane!

Gaff

Be thankful that you can specify specific brands and models.

You might want to check the entire bid package. There may be clauses in the contract portion
that allows substitution. It may be “or equal” or “approved equal”, but find out if its there. If there is an “approved” equal, find out if you are doing the approving. If it just says “or equal”, that could be a problem.

There may be an “exceptions” section. A vendor may be able provide a bid for most of the exact items, but may be allowed to offer substitutes for others.

Do you know if there are vendors who can provide all of your items? (That is, is there a single vendor or supply house that can quote every single item.) Do you have any control over who can bid? (If it’s a public notice, then anyone can bid, but on the other hand, there may be a list of qualified bidders/vendors that the purchasing/procurement department uses.) Will vendors be allowed to bid on just part of the list? [I wrote all this on the assumption that there is just one bid package – Are there going to be multiple bid packages, based on general categories of equipment, such as one for cables/connectors, another for anything to do with lights, etc. Multiple bid packages will make a little more work for you and your purchasing department but it could make the overall bidding easier. For example, a cable supplier couldn’t bid on the lights if it was a single bid package, but he might try anyway, either taking an exception on the lights or trying to find a subcontractor.]

Do you know if you can purchase some items from one vendor and other items from another vendor? (I suspect not, but it would depend on how the bid is structured. For example, if the bid/contract was structured as lump sum for the whole list, you may not see individual prices or even be able to break it out.)


Joe
 
Duraflex for your DMX cable. Best by a mile with twisted pair and double shielding.

Lex pin connectors would be my choice. The pins are replaceable and insulated holes through the connectors allow them to be tied together.

Light Source, Optikinetics and Global Truss all offer quality rated Cheeseborroughs.
 
Gaff
Be thankful that you can specify specific brands and models.
You might want to check the entire bid package. There may be clauses in the contract portion
that allows substitution. It may be “or equal” or “approved equal”, but find out if its there. If there is an “approved” equal, find out if you are doing the approving. If it just says “or equal”, that could be a problem.
There may be an “exceptions” section. A vendor may be able provide a bid for most of the exact items, but may be allowed to offer substitutes for others.
Do you know if there are vendors who can provide all of your items? (That is, is there a single vendor or supply house that can quote every single item.) Do you have any control over who can bid? (If it’s a public notice, then anyone can bid, but on the other hand, there may be a list of qualified bidders/vendors that the purchasing/procurement department uses.) Will vendors be allowed to bid on just part of the list? [I wrote all this on the assumption that there is just one bid package – Are there going to be multiple bid packages, based on general categories of equipment, such as one for cables/connectors, another for anything to do with lights, etc. Multiple bid packages will make a little more work for you and your purchasing department but it could make the overall bidding easier. For example, a cable supplier couldn’t bid on the lights if it was a single bid package, but he might try anyway, either taking an exception on the lights or trying to find a subcontractor.]
Do you know if you can purchase some items from one vendor and other items from another vendor? (I suspect not, but it would depend on how the bid is structured. For example, if the bid/contract was structured as lump sum for the whole list, you may not see individual prices or even be able to break it out.)
Joe

Hey Joe,
The bad thing is that state law is really tight on most of this. The good thing is that our purchasing department has welcomed my full participation. I believe I am going to be able to stipulate that any substitutions must be approved by me. I'm writing the package so it's flexible where acceptable (like DMX cable and Cheesboroughs) but locked in tight where I want (only Source 4 ellipsoidals).
I had a meeting with my preferred local dealer's custom sales guy yesterday and I know that they can supply everything on my list... unfortunately they still have to win a sealed bid. The truth is everything is pretty standard and there are many larger dealers who should easily be able to provide everything in the package.
I have no control over who can bid. It all gets published on a state website so that anyone can bid. I believe we have to purchase everything that is in the same bid package from the same vendor. I'm trying to break it up into several packages so that my favorite Audio Vendor for example gets a shot at part of it. I'm hoping that our friend Bill can have a crack at some of my money... but even the small packages need to have at least a woman owned business, a minority owned business, and three other businesses bid.
So the most important thing for me is to specify with as much detail as possible.
 
Going back to GSP connectors... I'm guessing that the "pressure plate" is the style that I'm used to where you crimp 3 spade connectors on and screw them down. I've never seen the Crimp Lug. Van doesn't seem to like them. Do I have the two styles named correctly? Can someone describe Crimp Lug to me? Anyone think I should go with crimp lug instead of Pressure plate?

I should have just started one thread called "Gaff's personal problems"...
 
The problem with a thread like that gaff is half of it would be filled with your war on metric voodoo and you'd never get any answers.
 
The problem with a thread like that gaff is half of it would be filled with your war on metric voodoo and you'd never get any answers.

True... I have a lot of problems...

Pressure Plates vs Crimp Lugs anyone?
 
What I was calling the "crimp Lugs" is the kind that has about a 3/16" hole at the back of each pin. You strip the insulation off the wire, put this little steel ferrule < sp?> over the end of the wire strands then insert it into the hole, then you tightten the screw. My issue arises from the fact that, if you over tighten the screw, even a little, the walls of the ferrule break, and then cut through, strands of wire. I have worked on instruments, straight from the factory, that had as few as 2 sttrands of wire remaining in a given conductor. Some were cut completely. Pressure plate sounds a whole lot more like the style of mechanism you see on a twistlock.
 
What I was calling the "crimp Lugs" is the kind that has about a 3/16" hole at the back of each pin. You strip the insulation off the wire, put this little steel ferrule < sp?> over the end of the wire strands then insert it into the hole, then you tightten the screw. My issue arises from the fact that, if you over tighten the screw, even a little, the walls of the ferrule break, and then cut through, strands of wire. I have worked on instruments, straight from the factory, that had as few as 2 sttrands of wire remaining in a given conductor. Some were cut completely. Pressure plate sounds a whole lot more like the style of mechanism you see on a twistlock.

Yeah I've seen some things similar to what you describe as crimp lug in the dash of my car. No thanks. I'll take the old fashioned route. It's really easy to see if they are in good shape or not.
 
True... I have a lot of problems...
Pressure Plates vs Crimp Lugs anyone?

I've bought and installed at least 6 brands/types of GSP connectors and hands down the best (and easiest to install) were the BATES connectors. They offer clear tops, and have the easiest method of attaching the wires.

Unlike the Union connectors where you have to crimp the wire into a spade or ring connector first, and then balance the little screw and lock washer on top (Ugh!!), the Bates allow you to slide a little nickel sleave over the wire, and just insert it into the backs of the pin, and you tighten the little screw down onto it to secure it in place. They are SOOOOOO easy to use.

Once you buy BATES, you'll never go back. Spend the $5 and try one to see.
 
I've bought and installed at least 6 brands/types of GSP connectors and hands down the best (and easiest to install) were the BATES connectors. They offer clear tops, and have the easiest method of attaching the wires.

Unlike the Union connectors where you have to crimp the wire into a spade or ring connector first, and then balance the little screw and lock washer on top (Ugh!!), the Bates allow you to slide a little nickel sleave over the wire, and just insert it into the backs of the pin, and you tighten the little screw down onto it to secure it in place. They are SOOOOOO easy to use.

Once you buy BATES, you'll never go back. Spend the $5 and try one to see.

Those are exactly what I've been talking about! I can see them being useful, speedy even, but you have to drive home the idea that Over tightening the screw results in carnage.
 
Hmm... I think maybe I better just stay with the product I know. It takes a while to crimp on those extra spades but you know it's all done really well.
 
<but even the small packages need to have at least a woman owned business, a minority owned business, and three other businesses bid.>

Ahhh... there is nothing like American free enterprise where the market determines the outcome...
 

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