Lincoln Lights Posted October 16, 2012 Share Posted October 16, 2012 I need some formal explanation on this so I may better understand my layout and decripbe it correctly.What is the diff. between daisy chain and splitting something. Thanks Link to comment Share on other sites More sharing options...
Max-Paul Posted October 16, 2012 Share Posted October 16, 2012 Daisy chaining is when a single line goes from point A to B to C to Xn. Splitting is when a single line goes to A to B to C and D (thats two lines leaving B. One going to C and another going to D.In order for RS-485 to be able to go 1000' and to minimize reflected signal to interfere with other signals. RS-485 needs to daisy chain. If you understand how to tune a C.B. or Amateur Radio antenna. If the antenna is not the right length the energy wave will not reach the right lobe and power is reflected back into the transmitter. This is also seen with the signal on a RS-485 line. But not exactly but the concept is there. If you have long T taps or improperly ran splits. These can induce those reflections and the receivers at the controllers will see a mix of two signals and unable to decipher the true command. Link to comment Share on other sites More sharing options...
edvas69 Posted October 16, 2012 Share Posted October 16, 2012 (edited) Best explained with a picture (taken from the ACL e1.31 presentation) Edited October 16, 2012 by edvas69 Link to comment Share on other sites More sharing options...
Lincoln Lights Posted October 17, 2012 Author Share Posted October 17, 2012 so if i have the 3 way splitter is it possible to do one or the other...for example... -= or =- will represent a three way splitter."daisey chain"signial in bottom =- device one one the other side and continued line out top of =- side."splitting"signal in -= and two out puts going to to different devices? Link to comment Share on other sites More sharing options...
Tim Fischer Posted October 17, 2012 Share Posted October 17, 2012 so if i have the 3 way splitter is it possible to do one or the other...for example... -= or =- will represent a three way splitter."daisey chain"signial in bottom =- device one one the other side and continued line out top of =- side."splitting"signal in -= and two out puts going to to different devices?Max-Paul already answered this above:In order for RS-485 to be able to go 1000' and to minimize reflected signal to interfere with other signals. RS-485 needs to daisy chain. If you understand how to tune a C.B. or Amateur Radio antenna. If the antenna is not the right length the energy wave will not reach the right lobe and power is reflected back into the transmitter. This is also seen with the signal on a RS-485 line. But not exactly but the concept is there. If you have long T taps or improperly ran splits. These can induce those reflections and the receivers at the controllers will see a mix of two signals and unable to decipher the true command. Link to comment Share on other sites More sharing options...
Lincoln Lights Posted October 17, 2012 Author Share Posted October 17, 2012 please forgive my ignorance... But I am on the 5 yard line of understanding this, and the last bit of his answer is in "greek" and I am listening in "not greek"Is a t tap a three way splitter? I think I will buy a enttec splitter to imporve signal to various sections of my design, but I still need to run signal to my controllers. I was able to test my 16 channel section that is going to run my mega tree, and the results were "passing". 16 strips, only one flashing / not behavong. I used a terminator on that controller, and all was well. Link to comment Share on other sites More sharing options...
edvas69 Posted October 17, 2012 Share Posted October 17, 2012 (edited) You cant just split the signal as this will cause signal reflections which cause flickering, what you need is a DMX splitter like this one shown here that optically isolates the signal from eachother.You can get away with splitting the signal if the distance between the controller and the data split are close like what is done with the holiday coro controllers but the more connected in a circuit the higher chance that you may get this flickering and signal reflection or if you have the distnace to far away from where you split the data fromIf you are using many of the holiday coro controllers then i reakon that this would be a good reccomendation to minimse the amount of reflected data that may be generated with many of these controllers hooked up, plus it allows for any fault finding to be a lot easier if a controller or power supply was to create issues as the DMX data circuit is split up into sections. Edited October 17, 2012 by edvas69 Link to comment Share on other sites More sharing options...
Max-Paul Posted October 17, 2012 Share Posted October 17, 2012 Gee, there are differences I believe between the standard LOR RS-485 and this DMX stuff. I am not familiar with the needs and requirements of DMX. Sorry I might have given you bad info. Yet you are to blame for not fully presenting your question. It is natural to presume you where talking about the standard mode of communication, RS-485. Link to comment Share on other sites More sharing options...
Don Posted October 17, 2012 Share Posted October 17, 2012 LL,Check your PM's. Will get you going there. Link to comment Share on other sites More sharing options...
Lincoln Lights Posted October 17, 2012 Author Share Posted October 17, 2012 thanks for your help everyone... as my wife says, I will be locking myself in "Dr. Cockroach's Lab" tonight. As I layout and test, I will PM back. I will be ordering a splitter as well this month to improve layout design. Link to comment Share on other sites More sharing options...
Recommended Posts