# Max length of running a dmx daisy chain.



## stonehedge99

Hi,

I want to run a single length 360' feet (120 meters) of dmx cable (actually high quality mic cable with a dmx terminator which i will be using at the end) for a season run install, it wont be permanant, just for a month and then ill have to store them till the next season at maybe a different venue.

This line of 360' is ofcourse made of certain lengths to accomodate 10 moving heads and 10 scrollers on the line. Will my line be reliable with 20 fixtures spread out over a length of 360' ?

Or is it better to split the signal (http://www.ebay.com/itm/XLR-cannon-...485?pt=LH_DefaultDomain_0&hash=item3a635bc005) at the beginning and then send one run for the backdrop trusses and one for the foreground lighting. This method reduces 70' on my 360' cable run so it will only be 290'. Would this make any difference at all ?

Regards


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## BillESC

First, welcome to Control Booth.

Second, you will need REAL DMX cable for this application since the run it long and connections are many.

Third, you can NOT split a DMX signal using an XLR twofer. It can only be done using an opto-isolator.


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## derekleffew

stonehedge99 said:


> ...Or is it better to split the signal (XLR(cannon)female to 2 XLR male y splitter adapter 10cm | eBay) at the beginning and then send one run for the backdrop trusses and one for the foreground lighting. This method reduces 70' on my 360' cable run so it will only be 290'. Would this make any difference at all ?




BillESC said:


> ...Third, you can NOT split a DMX signal using an XLR twofer. It can only be done using an opto-isolator.


And, even if you _could_ use a two-fer (again, emphatically stating that you *cannot*), the one you cited is going the wrong way. You'd need one with one male and two females.

The suggested limit of a DMX512 run, using proper DMX cable, is 1000'-1500', so your set-up, with 20 devices over 360', is not an issue. I have done several runs over 500' of mic cable with 20+ fixtures. Be sure to use a terminator, DMX. See also the rather lengthy recent thread http://www.controlbooth.com/forums/lighting-electrics/27615-ongoing-debate-mic-cable-dmx.html .


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## porkchop

You shouldn't use mic cable, but if that's what you've got then try and and make sure you use a terminator. Whether or not it will work reliably is going to depend on just how accurate you need it. If you're ok with a little bit of inconsistency and the possibility of seeing the lights wobble a little in cue then you ought to be fine. If you're not ok with that you might be calling up a rental house and getting some real DMX cable. Either way don't use a Y-cable to split the signal.


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## stonehedge99

Hi Bill,

Thanks for the warm welcome. Much appreciated.

Derek > Yes. I had no other option because the guys on my side of the globe dont sell technically specific DMX cable. So i had no other option but to buy high quality mic cable. I asked him which costliest variety he had and picked up that. I read the dmx debate, and it scares me more now . But im keeping my fingers crossed. I have not much time to R&D for the particular project im doing and so cannot locate the exact kind of cable. And here people who deal are like just traders who know nothing technically about the lights. The guy who sold me the moving heads doesnt know what a dmx terminator is. He doesnt know what kind of cable he has but he has cable that people use to control heads. Thats all they know.

I will DEFINTELY be using a terminator by making one myself. Thats why i mentioned ill be using one in my original post/question. Its not worth risking it for the price of a 120 ohms resistor.

But i have no option but to use this cable now. The ones on ebay are five times costlier. How much do you think i should pay for a 10 meter cable with connectors ? If you guys know any ebay item that ships worlwide do post in an item number or two that i can consider importing. But thats going to take time to reach me too.

Also to explain my plan a little more. From my control desk the signal first goes (thru this XLR cable that ive already got) for a distance of 70 feet after that it hooks up to the 10 moving heads and each head links to the next one using the cable set that came with the heads respectively. Then finally the 10th moving head sends the signal out via another 70 feet of the XLR cable in question which then links to the front lighting which are all daisy chained to each other using the cable bits that came with them originally. So the mic cable that ive bought is esentially 70' + 70' in this 360' feet run. I dont know if this pattern of usage matters but just thought ill mention it.

Brett > Like you said, at this moment i have nothing else but this option Brett. Ill still look out for some import options. Its very expensive to import these to my country. And if customs gets it they'd slap on another 50% duty fee as they've done to me before. Heavy and large sized boxes attract their attention. Imagine paying $200 for 50' of dmx cable.

Thanks


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## icewolf08

There are many online dealers that sell theatrical products who would probably be happy to ship them to you. Going to eBay for theatre products often results in overpriced items. There are plenty of US and European based dealers who would be happy to help you out, and I am sure there are probably dealers closer to you as well.

Just food for thought.


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## josh88

icewolf08 said:


> There are many online dealers that sell theatrical products who would probably be happy to ship them to you. Going to eBay for theatre products often results in overpriced items. There are plenty of US and European based dealers who would be happy to help you out, and I am sure there are probably dealers closer to you as well.
> 
> Just food for thought.



What ice wolf says is true, and even amongst dealers one needs to remember that just because a product is the most expensive it isn't necessarily the
Highest quality. Don't use that as a judge of quality.


Sent from my iPod touch using Tapatalk


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## stonehedge99

I agree that just because its costly doesnt mean its good quality. Similarly the same applies the other way too. Just because its very cheap doesnt neccesarily mean its bad. In my industry ive purchased very expensive equipment pertaining to other industries / line of work etc and there have been instances when cheap non-brand items have exceeded the qaulity of the branded version or been designed better. Ive also bought expensive stuff that never even worked.

Any ideas which dealer in asia or USA would be able to internationally ship proper dmx cable at reasonable prices ?

I only found a lot of Chinese suppliers and they dont know squat about quality, they just know to replicate and sell, and they can replicate high quality or even low quality. But not all of them are that way maybe. But most of them ive dealt with are that way. They can hardly speak english if at all. And they will sell you standard mic cable and if you asked if its real DMX cable you'd get a shrill hi pitched voice yelling "yeah yeah" without even understanding what you asked.

Thanks


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## n1ist

Two other ideas come to mind:

- Do you have cat-5 cable available? Shielded stranded cat-5 works fine for DMX and may be easier to get
- Sticking an opto-splitter half way (say at one of the movers) will regenerate your signal.

/mike


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## JD

Do you know the impedance of the cable? (would be in the manufacturer's spec sheet.) For DMX, that is a more important factor then the cost. High quality mic cable usually has very low capacitance, so that is good, but look for that number. If it is 50 to 60 ohms, you may have problems. If it is 100 to 120 ohms, then you are good to go. 

Note: Impedance can not be measured with a common meter. It is a factor of the inductive and capacitive loading of a line used as a transmission line.


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## stonehedge99

Hi,

I actually just located a dealer in CAT5 cable (He said it has a 150 ohms rating) as i was seriously considering it as an option since many suggest it to be a good alternate.

How good is it ? Equal in performance to original DMX cable ? I also understand its the same thing used in LAN cabling. Plz do let me know. Also will this 150 ohms class be useful for DMX ?

Finally CAT5 has so many strands and i dont know how to get it soldered at the male and female connectors, any links or images that could point me to a clue would be useful when getting them soldered.

Thanks


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## derekleffew

See the video in this post. 

For the proper pin-out of DMX over Category cable, see Pathway Connectivity Inc. - Cat5 Pinout for DMX :

> Category wire is not recommended for loose or temporary cabling. The use of RJ45 connectors for DMX equipment should be restricted to patch bays in access controlled rooms and should not be used for the direct connection of portable equipment.


Same/similar information at ETC KnowledgeBase: DMX over CAT5 .

In my opinion, CAT5+ cable is not the magic solution to DMX transmission, for a variety of reasons:
1. If used outside of metal conduit, it must be STP rather than UTP, which is as rare as proper DMX cable.
2. For durability in portable use, must be stranded rather than solid. Again, rarer than DMX cable.
3. The RJ45 connector was never meant to be used on a daily basis. Terminating connectors other than IDC is problematic.

-----

It looks like The Lighthouse (Facebook page link) is the largest lighting company in Sri Lanka. Have you contacted them?


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## stonehedge99

OK so now even CAT5 is not good enough . Why does dmx happen to be so rare ?
Ive located a guy offering CAT5e STP. They told me they have the stranded type. Will this help ? Will these cables be easy to solder onto 3 pin dmx xlr connectors ?

Regards


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## FMEng

Shielded Cat 5 would be preferable, but I see no reason why unshielded Cat 5 wouldn't work. The balancing of the data signal is whan eliminates most electrical noise, not the shield. The impedance of Cat 5 is close enough to work well with DMX, especially compared to mic cable. 

If you make a DMX cable with Cat 5, simply use the orange/white twisted pair for pins 2&3 and cut off the others. It'll solder in an XLR just fine. Pre-made Cat 5 jumpers are readily available and they are stranded conductors. Buy them and cut off the RJ-45 plugs. Bulk cable for installation is solid conductor, and should be considered a throw away after a use or two as repeated handling will damage it.


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## stonehedge99

Hi FM,

Ive found someone offering stranded type. I think what you mean by bulk cable is that the copper wire is a solid thick single wire right ? So they are good for permanant installs if im understanding right.

The stranded looks like typical braided hair or crossed type ? I also see some CAT5 cables listed as twisted or straight. Are they referring to the solid and stranded types ? When you say premade Cat5 jumpers are available and they are stranded conductors, are you basically reffering to the readymade computer RJ45 jack, and ur suggesting i buy the 10 mtr units and cut off the plugs right ?

Thanks


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## JD

I always take the other six conductors and solder them to pin 1. (Kind of a wee bit like a funky braided partial shield.) The impedance works fine. It is fully acceptable to use it in conduit. It is not recommended to use it out of conduit on it's own, but many do. The solid conductors have a limited amount of flexing they can do before they break. Stranded is better, but as said above, harder to find in bulk. Use ONLY one pair for the 2/3 data line, do not parallel. I'll let the 3 pin XLR connector part slide as I am guilty of this as well. (DMX is 5 pin only! Despite the fact that pins 4 and 5 are not used.)


stonehedge99 said:


> I think what you mean by bulk cable is that the copper wire is a solid thick single wire right ?



Just means a continuous length on a roll (Like 250, 500, or 1000 feet)


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## stonehedge99

Everywhere i read it says CAT5 is not to be used for portable installs. Im needing this for a touring show. But not often. Now i have a one month season run coming up. Next after that will be 3 months later and so on. But ill have to reuse my cables.

Also on a sidenote, i just noticed the printing on my existing dmx cables and it says AVVR 300/300 V. Does that mean its compatibile for DMX ?

Thanks


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## stonehedge99

I think CAT isnt for me because ill be taking down this setup and putting it back together at different locations for different seasons. So im thiking about buying something like this..can you guys give it a look and tell me what you feel. Secondly i think they dont ship internationally. So if any of you can tell me where i can buy this with international shipping and if preferably at a lesser cost ? Ill be buying about 10 nos of 25' packs.

Accu-Cable AC3PDMX25 3-Pin DMX Cable, 25 Feet

Any ideas about this brand and is it technically specific for a 120 meter run or say 140 meters allowing room for future proof addition of some fixtures. ANy sources that would offer this a little cheaper and with maybe reasonable shipping costs ?

Thanks


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## techieman33

That would work. But instead of just buying 25' pieces you need to think about your spacing. Your probably going to want a longer cable to get from the lighting console to backstage, having to attach lots of 25' pieces is just begging for problems in my opinion. 250'-300' is pretty standard length for something like that but it all depends on the kinds of venues you'll be playing in. You'll also probably want some 25'-50' lengths in case you need to go further than that, and for the longer gaps between fixtures. And also some 5'-10' lengths for the shorter gaps between fixtures. It all depends on what you need for your specific show and the venues that your going into.


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## church

JD said:


> Do you know the impedance of the cable? (would be in the manufacturer's spec sheet.) For DMX, that is a more important factor then the cost. High quality mic cable usually has very low capacitance, so that is good, but look for that number. If it is 50 to 60 ohms, you may have problems. If it is 100 to 120 ohms, then you are good to go.
> 
> Note: Impedance can not be measured with a common meter. It is a factor of the inductive and capacitive loading of a line used as a transmission line.



JD is correct the impedance is a factor of capacitance and inductance and the impedance of both of these is a function of the frequency of the signal. becomes interesting for data signals because a 100kHz square wave needs a cable that can easily handle the eleventh harmonic without the cable impedance changing dramatically. Cable construction can result in changes in inductance and capacitance at higher frequencies which appears as a significant impedance change to the higher frequencies resulting in an impedance mismatch. This results in signal reflections which appear as rounding of the slope and corners producing errors in the receivers which is why the impedance issue and the need for good quality cable becomes an issue.


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## stonehedge99

I located a chinese seller who says their cable is 3 pin dmx and rated @ 120 ohms. Will that be correct for a 360 ft run ?

Do let me know as in this case i wont have to mess around with soldering and risk any mistake.

Thanks


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## dramatech

Hi Stonehede99

Buy the Chinese DMX cable. The fact that you are using equipment that uses 3 pin XLR sort of desinates that it isn't the top of the line. The Chinese 120 ohm cable will be about as good as you are going to find, that you can get in, or shipped to Sri Lanka. 
You will have to forgive many who post on CB. They can tend to be a bit snobbish, when it comes to DMX and it's use. In an ideal world their snobishness is good. Also their comments are good and valid for many of the readers of this type of post. Especially those who live where they can get the best. Many of the CB readers are trying to function with a very tight budget. There are some things that can be cut in quality in order to save a buck or two. DMX is one of those things in theatre lighting that the user should go with the best they can afford. 
In the case of places where most of this equipment is not available or is just now becoming available, you go with the best that you can get. Many who have posted in this thread have no idea of the situation in Sri Lanka. While much of what has been posted is good advice, it ignores that your choices are probably Chinese DMX cable of slightly less quality, Cat 5, audio cable zipcord or fence wire. The Chinese DMX cable is probably your best bet of what is available to you.

Tom Johnson


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## stonehedge99

Hi Tom,

Thanks for understanding my situation and explaining. Will this chinese cable @ 120 ohms work for a 360 ft run with 20 fixtures on that line ?

I actually did feel the talk about inverse law and square wave went over my head in terms of understanding. I understand they exist, but like you said in places where they have access to the best. Here i dont even know if the dmx cable i order from the USA will even reach me. The technicians here at my place are mostly illiterate, can speak proper english, at least the tech guys in the dmx lighting world and suppliers etc are hardly well read, most of them actually manpower labourers.

I think anyhow the technical perfection detail will still help those that are looking for it when they visit this thread.

Regards


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## dramatech

The DMX standard says that with 120 ohm cable and proper termination that you should be able to daisy chain up to 32 receiving devices and for much greater distances than 360 feet.
Having said that, here are a few things to watch out for. The more connectors in the chain, the more possibility for problems. Not all devices that use DMX for control signals use the proper chips for that task. Some of the very cheap DMX devices use digital circuitry that is not RS485 tranceivers. The more of these type of devices in the chain, the greater the potential for problems. I personally don't know these devices, but they have been mentioned in general on the lightnetwork forum by Mats Karlsson, who I consider to be just about the most intelligent overall lighting person around.
The solution to your problem if 20 devices causes too much load, is an optosplitter. I realize that might not be the easiest thing to purchase in Sri Lanka. There are many different splitters available. The best is Doug Fleenor, but there are some pretty good Chinese units marketed under Elation, neo-neon and ohers. I think that your best bet might be an Enttec. That might not be the correct spelling, but I believe that it is built in Australia, so it might be easier to purchase than something from the US or Europe. It has one input and 4 outputs. It comes with either 3 or 5 pin XLRs, and sells for $100US in the US.
I would go with the Chinese cable, use the longest continuous lengths on the long distances, to reduce the number of connectors. Check each device to make sure there isn't a terminator switch that is turned on. Terminate the end of the line with a proper 120 terminator or a resistor across pins 2 and 3. Then if you have a chance, purchase an Enttec optosplitter and have it ready to upgrade your system to a greater reliability as you go along.
I hope this helps, just use common sense and check your install as you go.

Tom Johnson


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## Tex

dramatech said:


> The fact that you are using equipment that uses 3 pin XLR sort of desinates that it isn't the top of the line.



High End Systems would disagree. 3 pin connectors show up in all levels of dmx devices, even though they don't meet the standard.

Sent from my GT-P7510 using Tapatalk


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## dramatech

Tex said:


> High End Systems would disagree. 3 pin connectors show up in all levels of dmx devices, even though they don't meet the standard.
> 
> Sent from my GT-P7510 using Tapatalk



True, very true, but they are even changing and must have read the USITT standards.

Don't get me wrong, I have several items that started out 3 pin, but I have changed their connectors to 5 pin. There are many decent devices that use 3 pin XLR, but at the same time, the really crappy ones almost never use 5 pin XLR. The whole 3 pin versus 5 pin is a discussion/argument that will persist for ever and is really good material for folks that would rather argue lighting than actually spend all of their time doing it. Oops! did I just open a huge door to get flamed. Oh well, I have an asbestos suit made from all that wire I took out of Electro-Control fresnels, in order to bring them up to date.

Tom Johnson


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## LXPlot

dramatech said:


> I think that your best bet might be an Enttec. That might not be the correct spelling, but I believe that it is built in Australia, so it might be easier to purchase than something from the US or Europe. It has one input and 4 outputs.
> Tom Johnson



The opto-splitter in question is this one. Enttec sells it for 125 USD. You will most likely also need a 3-pin to 5-pin adapter, for instance this one, if you want to use the opto-splitter with your 3 pin cable. I'm not familiar with the general price of shipping or customs to Sri Lanka, but I'm guessing it's probably a lot. Unfortunately, you won't find anything reliable cheaper (barring Chinese off-brand stuff, which is a dice roll).

Good luck with all of this.


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## stonehedge99

Will this product help. Its a little cheaper too. .

It splits one input into 8 outs and amplifies the signal too ???

Will this help ?

Thanks


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## dramatech

stonehedge99 said:


> Will this product help. Its a little cheaper too. .
> 
> It splits one input into 8 outs and amplifies the signal too ???
> 
> Will this help ?
> 
> Thanks



When it comes to splitters, there are ones that just split the signal by using multiple transceiver chips. One is used for the input or receiving the signal. The output of that chip is then sent to how many ever outputs through one chip per output in the transmission mode. This type of splitter uses only one power supply for all of the chips.
The most advanced splitter goes a bit further. It uses one chip for receive, one each chip for each output to transmit, but also uses and isolation chip on each of the output chips and uses separate power supplies to power the input circuitry, and one for each output. Those are referred to as Optoisolated splitters or generally in a shorter form as "optosplitter".
The advantage of the opto splitter is the security it provides to the devices attached. Let us say that you have many different types of devices that require the DMX signal. You may want to put all of the moving heads of one manufacture on one output. On another output, you may want to put all of your scroller power supplies. Other devices such as "shoebox dimmers" may go on several different outputs based on their location. Now if say one of the shoebox dimmers shorts internally putting mains power on the DMX line, It will only destroy the other devices on that output of the optosplitter. All of the devices on the other outputs will be protected because there is no direct signals with voltage on them that connect between ouputs.
The type that has no isolation through optical coupling risk the possibility of every device being damaged when one device shorts internally or cables shorting to higher voltages.
The device that you are looking at on ebay is almost for sure to be the non-optoisolation type distributor. Considering the price and the single power input. That having been said and considering the low cost and the 3 pin connectors, that you seem to have on the rest of your system, and the fact that they can probably ship from China to Sri Lanka, more easily than from the US or Europe, I would say that it would be worth your while. It mentions in the add and the broken english, "485". I think that means that it is splitting and distributing RS485, the transmission standard of DMX.
While isolation is desireable, having the ability to splitt some of your signals will certainly help with the distances. I think that I am going to buy one just to have as a backup for other things that I do at my theatre. I have 24 outputs of DMX, all isolated through out my theatre, and a couple of 4 output portable that I can use as neccessary. The price of that Chinese one is low enough for me to just buy one and take it apart to see how they have done it.

Tom Johnson


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## stonehedge99

Hey Tom,

I did a lot of searching and found that unit. It seems to be very cheap. But This unit seems to have protection for upto 1000v on the dmx line, something similar to opto isolation ????

Anyway heres one for almost the same price in the UK and this one is from a very prominent theatre supply house with the best part being this IS Opto Isolated. Check it out here. 

Thanks


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## dramatech

stonehedge99 said:


> Hey Tom,
> 
> I did a lot of searching and found that unit. It seems to be very cheap. But This unit seems to have protection for upto 1000v on the dmx line, something similar to opto isolation ????
> 
> Anyway heres one for almost the same price in the UK and this one is from a very prominent theatre supply house with the best part being this IS Opto Isolated. Check it out here.
> 
> Thanks



Both of the units that you indicated would probably be a better choice than the Chinese one that we discussed earlier. The one from the UK appears to have a drawing on the case, that would indicate that there is power isolation as well as the DMX signal isolation. It would be my guess that there are two seperate outputs that are power isolated, and each of those outputs has two seperate DMX outputs. This is common of the Elation splitters, only they do eight outputs divided into to four power isolations.

The New Zealand unit uses USB power which is 5 volts DC, and is the same voltage required to operate the DMX tranceiver chips. I therefore doubt that it has power isolation.

If I were you, I would purchase which ever unit can be delivered to Sri Lanka the easiest and the quickest. I think any of them would do a Good job for you. If I had to prioritize them based on what I can read and observe, I would rate the one in the UK best, the New Zealand next and the Chinese last. Just looking at a map, I would think that the one from China would be the easiest transportation wise and the UK and new Zealand routes are about the same distance, but the UK route would have more land line transportation. Good Luck, I think that you are pretty well versed at this point to get the DMX installed and pretty reliable.

Tom Johnson


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## stonehedge99

Ive ordered the dmx splitter/booster box. Hopefully it will arrive soon.

Meanwhile a small question that cropped up. Now that ill be sending one dmx signal from my controller into the distro box and then the dmx splits into 8 outs. Ofcourse ill be just using about 3 out runs from there. So output 1 will run for 100 ft, output 2 for 100', and the third also the same. Im planning to terminate each run at the end of the 100' run. Is this ok or termination is only ideal for a one single length run ?

Thanks


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## MNicolai

stonehedge99 said:


> Ive ordered the dmx splitter/booster box. Hopefully it will arrive soon.
> 
> Meanwhile a small question that cropped up. Now that ill be sending one dmx signal from my controller into the distro box and then the dmx splits into 8 outs. Ofcourse ill be just using about 3 out runs from there. So output 1 will run for 100 ft, output 2 for 100', and the third also the same. Im planning to terminate each run at the end of the 100' run. Is this ok or termination is only ideal for a one single length run ?
> 
> Thanks



You treat each output of the opto-isolator as an individual DMX run. So if you use outputs 1-3, at the end of each chain on each output you'll want a terminator. Distance has no factor in regards to terminating your signals. If your total DMX cable run on a given output is 20' or 200', you'd still use a terminator at the end of each chain.

Example:

Output 1 ---> Dimmer Pack ---> Dimmer Pack ---> Dimmer Pack ---> Dimmer Pack ---> Terminator
Output 2 ---> Scroller PSU ---> Scroller PSU ---> Terminator
Output 3 ---> Scroller PSU ---> Scroller PSU ---> Terminator
Output 4 ---> LED ---> LED ---> LED ---> LED --> LED --> Terminator
Output 5 ---> Unused (no terminator needed)
Output 6 ---> Unused (no terminator needed)
Output 7 ---> Unused (no terminator needed)
Output 8 ---> Unused (no terminator needed)

The nice thing about a proper splitter such as this is if something quirky happens on output #4 -- a bad cable with a shorted wire that causes devices to do weird things, the problem will only be witnessed on the devices connected to that output. Devices on output #6, #2, or any other output will still function normally.


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## stonehedge99

Ok each branched out run should be terminated. That was my guess, but thanks for endorsing it. So id have to get male plugs (all my devices are 3 pin dmx) and just solder a 120 ohms half watt resistor across pins 2 and 3 to turn them into termination plugs right ?


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## dramatech

That is correct.


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## stonehedge99

Thanks to all of you. Ill let you all know how it went. Meanwhile i forgot to ask if the 120 ohms resistor should go with a prefered polarity on the (i mean a particular resistor leg to pin 2) 2 and 3 pins or the resistor can be solder on either way.


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## MNicolai

stonehedge99 said:


> Thanks to all of you. Ill let you all know how it went. Meanwhile i forgot to ask if the 120 ohms resistor should go with a prefered polarity on the (i mean a particular resistor leg to pin 2) 2 and 3 pins or the resistor can be solder on either way.



Resistors have no polarity bias. They can be soldered either lead to either pin.


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## stonehedge99

Hi Guys,

I have got the DMX booster splitter with me and i have bought a small 12v power adapter to power it. I wanted to ask. Is this power adapter meant only for optional backup or the dmx booster always needs power to work. This is the chinese one ive metioned above see here.

Can someone tell me if this needs to be powered all the time by 12v and any idea what they mean by "12v-24v" printed on the splitter ????


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## Chris15

It needs power all the time and will work happily with an input of anywhere between 12 and 24 volts.


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