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dmx_basics:dmx_in_practice

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dmx_basics:dmx_in_practice [2013/03/12 22:03]
127.0.0.1 external edit
dmx_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