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dmx_basics:dmx_in_practice

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dmx_basics:dmx_in_practice [2013/03/12 22:03] – external edit 127.0.0.1dmx_basics:dmx_in_practice [2015/05/27 17:19] (current) russwig
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 If a fixture like above starts on address 20 and uses 12 addresses then the next fixture address must be at address 32 to avoid overlapping.\\ If a fixture like above starts on address 20 and uses 12 addresses then the next fixture address must be at address 32 to avoid overlapping.\\
 \\ \\
-The maximum no of fixtures in a chain are 32 and his is due to load on the driver circuit.\\+The maximum no of fixtures in a chain are 32 and this is due to load on the driver circuit.\\
 \\ \\
 The last fixture in the chain has to be terminated with a DMX end or terminator.\\ The last fixture in the chain has to be terminated with a DMX end or terminator.\\
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 **Why DMX end / termination**\\ **Why DMX end / termination**\\
 The DMX termination is a 120 ohm resistor.\\ The DMX termination is a 120 ohm resistor.\\
-DMX cable has a characteristic impedance of 120 Ohms. It is a bit complex to be described here but it is a complex high frequency calculation of inductorscapacitors, serial resistors and leak resistors in the cable is self. \\+DMX cable has a characteristic impedance of 120 Ohms. It is a bit complex to be described here but it is a complex high frequency calculation of inductioncapacitance, serial resistance and leakage resistance in the cable itself. \\
 The impedance 120 ohm can not be measured with a multimeter.\\ The impedance 120 ohm can not be measured with a multimeter.\\
-It is important to terminate the cable with 120 ohm to avoid reflection on the cable which courses the DMX signal to bounce back to the fixture.\\ +It is important to terminate the cable with 120 ohm to avoid reflection in the cable which causes the DMX signal to bounce back to the fixture.\\ 
-The reflected signal may course the fixture to mal function.\\+The reflected signal may cause the fixture to malfunction.\\
 See eventually: [[dmx_basics:dmx_measurements|]]\\ See eventually: [[dmx_basics:dmx_measurements|]]\\
-Some fixtures has a build in 120 termination that can be activated.\\+Some fixtures have a build in 120 termination that can be activated.\\
 \\ \\
 To build a DMX terminator/end see this link [[http://www.thedmxwiki.com/definitions/dmx_terminator| DMX Terminator]]\\ To build a DMX terminator/end see this link [[http://www.thedmxwiki.com/definitions/dmx_terminator| DMX Terminator]]\\
 \\ \\
-Additional for the optimal performance use cable with a characteristic impedance of 120 Ohms.\\ +Additionally, for optimal performance use cable with a characteristic impedance of 120 Ohms.\\ 
-Microphone cable can be used but for longer distance they may course the fixture to mal function.\\ +Microphone cable can be used but for longer distance may course the fixtures to malfunction.\\ 
-The reason is that audio cables has a higher capacitor part in the a characteristic impedance.\\+The reason is that audio cables has a higher capacitance and inherent impedance.\\
 \\ \\
-This reflection issue is also the reason for not to split the DMX signal with a Y cable.\\ +This reflection issue is also the reason for not splitting the DMX signal with a simple Y cable.\\ 
-Keep it in one line and if the signal are to be divided use a DMX splitter.\\+Keep it in one line and if the signal needs to be divided use a DMX splitter.\\
 \\ \\
 **Why Splitter**\\ **Why Splitter**\\
 Splitting the signal is the same problem as above.\\ Splitting the signal is the same problem as above.\\
-The load impedance don’t match 120 ohm and this course reflection and DMX signal bouncing forward and backward on the cable.\\+The load impedance don’t match 120 ohm and this causes possible reflection of DMX signal bouncing forward and backward on the cable.\\
 \\ \\
 The benefit of using a splitter that has building line drivers are that it is possible to have 32 fixtures on all the divided outputs.\\ The benefit of using a splitter that has building line drivers are that it is possible to have 32 fixtures on all the divided outputs.\\
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 \\ \\
 Finally if it is a optical/transformer isolated splitter then there are no electrical connection between the paths.\\ Finally if it is a optical/transformer isolated splitter then there are no electrical connection between the paths.\\
-This eliminate problems with ground loops and spikes when lamps are turned on.\\+This eliminates problems with ground loops and spikes when lamps are turned on.\\
 The controller is also protected this way.\\ The controller is also protected this way.\\
 \\ \\
dmx_basics/dmx_in_practice.txt · Last modified: 2015/05/27 17:19 by russwig

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