Wiring Smart Pixels - Revision history

ErnieHorning: Updated the Wiring Smart Pixels page to reflect current wiring practices used in DIY holiday displays. Added information about distributed ESP8266/ESP32 controllers, modern distributed power systems, updated voltage measurement recommendations, clarified the use of Ethernet cable versus standard PoE, and added guidance for current controller layouts while preserving the original engineering concepts and illustrations.

2026-07-20T11:11:23Z

Updated the Wiring Smart Pixels page to reflect current wiring practices used in DIY holiday displays. Added information about distributed ESP8266/ESP32 controllers, modern distributed power systems, updated voltage measurement recommendations, clarified the use of Ethernet cable versus standard PoE, and added guidance for current controller layouts while preserving the original engineering concepts and illustrations.

Ronp5683: /* Basic Recommendations */

2015-09-07T17:26:30Z

Basic Recommendations

Ronp5683 at 02:26, 8 July 2015

2015-07-08T02:26:04Z

Ronp5683 at 23:38, 5 June 2015

2015-06-05T23:38:56Z

Ronp5683 at 04:29, 5 June 2015

2015-06-05T04:29:15Z

Ronp5683 at 04:26, 4 June 2015

2015-06-04T04:26:02Z

Ronp5683: Created page with "The most important part of your show is the wiring. This heavily affects the cost, ease of setup/take down, and how easy it is to fix problems. It is important that you thorou..."

2015-06-04T01:19:42Z

Created page with "The most important part of your show is the wiring. This heavily affects the cost, ease of setup/take down, and how easy it is to fix problems. It is important that you thorou..."

New page

The most important part of your show is the wiring. This heavily affects the cost, ease of setup/take down, and how easy it is to fix problems. It is important that you thoroughly understand wiring, before you choose how you want to layout your show.

== How Many Pixels? ==

First, let me list some of the basic guideline that you should follow to ensure that you do not have issues with your hardware. These are guidelines which can be violated, but ensure that you clearly understand what you are doing.

1) Only drive fifty 5Vdc pixels without power injection.

2) Only drive one hundred 12Vdc pixels without power injection.

3) Do not use ground loops in your power.

== Wiring Methods ==

By far the least expensive method to drive smart pixels is with a large power supply powered through your controller. The only other components required is a power cable to the pixels. It is recommended that you use 16AWG extention wire in lengths of 10-15 feet, which is cheaper bought as an extension cord. The only cost for this layout is the controller and the wire.

[[File:Wiring_Direct_Power.PNG|600px|Left]]

If the pixels are further away from your controller, it is best to use a local power supply and Ethernet cable for the control lines. If you use Ethernet cable to drive the control signals, with 100 ohm source termination, it has been demonstrated to work at 100 feet. The drive chip used was an 74ACT541 versus the standard 74HCT541. The ACT parts have more current drive, which will improve your ability to drive the signal further.

[[File:Wiring_Local_Power.PNG|600px|Left]]

[[File:Wiring_Local_Pixel_Extender_.PNG|600px|Left]]

[[File:Wiring_POE.PNG|600px|Left]]

[[File:Wiring_POE_Pixel_Extender.PNG|600px|Left]]

[[File:Wiring_POE_Pixel_Extender.PNG|600px|Left]]

@@ Line 15: / Line 15: @@
 ) Multiple small controllers around the yard minimize wiring and cost.
-) Finally, you should be able to measure the current to your strings and determine the voltage at the end of a string. For pixels without internal regulators the voltage drop at the end of the string should be no more than 10%, 4.5Vdc for 5Vdc and 10.8Vdc for 12Vdc. The maximum voltage drop for strings with built in regulators depends upon the minimum input voltage for the regulator, so check the specifications for your specific pixels.
+a) Wi-Fi controllers based on the ESP8266 and ESP32 have become a common alternative to Ethernet controllers for individual props. Placing small controllers close to each prop can greatly reduce wiring, power injection requirements, and setup time.
 == Wiring Methods ==
@@ Line 21: / Line 23: @@
 '''Direct Power'''
-By far the least expensive method to drive smart pixels is with a large power supply powered through your controller. The only other components required is a power cable to the pixels. It is recommended that you use 16AWG extension wire in lengths of 10-15 feet, which is cheapest bought as an extension cord. The only cost for this layout is the controller, large power supply and the wire.
+By far the least expensive method to drive smart pixels is with a large power supply powered through your controller. The only other components required is a power cable to the pixels. It is recommended that you use 16AWG extension wire in lengths of 10-15 feet, which is cheapest bought as an extension cord. The only cost for this layout is the controller, large power supply and the wire. This has become one of the most common wiring methods for medium and large displays because inexpensive controllers can be placed close to the props they control, minimizing voltage drop and reducing the need for additional power injection. Many modern displays use smaller distributed power supplies or power supplies integrated with individual controllers instead of one large centralized supply. This reduces long power cable runs and often simplifies installation and troubleshooting.
 [[File:Wiring_Direct_Power.PNG|600px|Left]]
@@ Line 33: / Line 35: @@
 '''Local Power Supply with Pixel Extender'''
-In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allowing the ground between your lights and controller to vary up to ±7Vdc. By far this is one of the best methods to drive strings. It will always work at any distance, the input to the display element is an Ethernet cable and power is through an extension cord. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
+In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allowing the ground between your lights and controller to vary up to ±7Vdc. By far this is one of the best methods to drive strings. It will always work at any distance, the input to the display element is an Ethernet cable and power is through an extension cord. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards. Differential pixel extenders continue to be widely used for long cable runs where controllers cannot be located close to the props. Many modern controllers also offer built-in differential outputs or expansion receivers using the same concepts described here.
 [[File:Wiring_Local_Pixel_Extender_.PNG|600px|Left]]
@@ Line 53: / Line 55: @@
 The Ethernet jacks are rated at 1.5 amperes, and normally two pins are used. Nominally for commercial equipment the connectors are derated by 15 percent to 3.0 x 0.85 = 2.5 amperes. This would be the peak current through the cable.
 When choosing a DC to DC converter make sure that the module can support 3 amperes of continuous current. The LM2596 is a good example of what not to buy, it supports 3 amperes peak, with 1 ampere of continuous current.
 [[File:Wiring_POE.PNG|600px|Left]]
@@ Line 62: / Line 66: @@
 [[File:Wiring_POE_Pixel_Extender.PNG|600px|Left]]
 == Wiring and Controllers ==
 Another aspect of wiring to consider is the type of controller you buy. A controller may support 1 to 4 universes of lights or 170 to 680 pixels per output. So this would affect your layout of your wiring. For example, in the picture below, you can wire four mini-trees with each using one output, or all four using the same output. The first version allows you to use a common power supply if the trees are close, and the second requires power to be injected into the string.
 [[File:Mini-Tree_Layout.PNG|600px|Left]]

@@ Line 5: / Line 5: @@
 First, let me list some of the basic recommendations as a starting point for your display.
-) Only drive fifty 5Vdc pixels without power injection.
+) Only drive fifty 5Vdc pixels without power injection (assumes standard 60mA per pixel).
-) Only drive one hundred 12Vdc pixels without power injection.
+) Only drive one hundred 12Vdc pixels without power injection (assumes standard 60mA per pixel).
 ) Do not use ground loops in your power.

@@ Line 15: / Line 15: @@
 ) Multiple small controllers around the yard minimize wiring and cost.
-) Finally, you should be able to measure the current to your strings and determine the voltage at the end of a string. For pixels without internal regulators the voltage drop at the end of the string should be no more than 10%, 4.5Vdc for 5Vdc and 10.8Vdc for 12Vdc. The maximum voltage drop for strings with built in regulators depends upon the minimum input voltage for the regulator, so check the specifications for the pixels.
+) Finally, you should be able to measure the current to your strings and determine the voltage at the end of a string. For pixels without internal regulators the voltage drop at the end of the string should be no more than 10%, 4.5Vdc for 5Vdc and 10.8Vdc for 12Vdc. The maximum voltage drop for strings with built in regulators depends upon the minimum input voltage for the regulator, so check the specifications for your specific pixels.
 == Wiring Methods ==
@@ Line 21: / Line 21: @@
 '''Direct Power'''
-By far the least expensive method to drive smart pixels is with a large power supply powered through your controller. The only other components required is a power cable to the pixels. It is recommended that you use 16AWG extension wire in lengths of 10-15 feet, which is cheaper bought as an extension cord. The only cost for this layout is the controller, large power supply and the wire.
+By far the least expensive method to drive smart pixels is with a large power supply powered through your controller. The only other components required is a power cable to the pixels. It is recommended that you use 16AWG extension wire in lengths of 10-15 feet, which is cheapest bought as an extension cord. The only cost for this layout is the controller, large power supply and the wire.
 [[File:Wiring_Direct_Power.PNG|600px|Left]]
@@ Line 27: / Line 27: @@
 '''Local Power Supply'''
-If the pixels are further away from your controller, it is best to use a local power supply and Ethernet cable for the control lines. If you use Ethernet cable to drive the control signals, with 100 ohm source termination, it has been demonstrated to work at 100 feet. The drive chip used was an 74ACT541 versus the standard 74HCT541. The ACT parts have more current drive, which will improve your ability to drive the signal further. The local power supply adds some additional cost for power.
+If the pixels are further away from your controller, it is best to use a local power supply and Ethernet cable for the control lines. If you use Ethernet cable to drive the control signals, with 100 ohm source termination, it has been demonstrated to work to at least 100 feet. The drive chip used was an 74ACT541 versus the standard 74HCT541. The ACT parts have more current drive, which will improve your ability to drive the signal further. The local power supply adds some additional cost for power.
 [[File:Wiring_Local_Power.PNG|600px|Left]]
@@ Line 33: / Line 33: @@
 '''Local Power Supply with Pixel Extender'''
-In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allow the ground between your lights and controller to vary up to ± 7Vdc. By far this is one of the best methods to drive strings. It will always work at any distance, the input to the display element is an Ethernet cable and power is through an extension cord. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
+In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allowing the ground between your lights and controller to vary up to ±7Vdc. By far this is one of the best methods to drive strings. It will always work at any distance, the input to the display element is an Ethernet cable and power is through an extension cord. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
 [[File:Wiring_Local_Pixel_Extender_.PNG|600px|Left]]
@@ Line 53: / Line 53: @@
 The Ethernet jacks are rated at 1.5 amperes, and normally two pins are used. Nominally for commercial equipment the connectors are derated by 15 percent to 3.0 x 0.85 = 2.5 amperes. This would be the peak current through the cable.
-When choosing a DC to DC converter make sure that the module can support 3 amperes of continuous current. The LM2596 is a good example not to buy, it supports 3 amperes peak, with 1 ampere of continuous current.
+When choosing a DC to DC converter make sure that the module can support 3 amperes of continuous current. The LM2596 is a good example of what not to buy, it supports 3 amperes peak, with 1 ampere of continuous current.
 [[File:Wiring_POE.PNG|600px|Left]]

@@ Line 33: / Line 33: @@
 '''Local Power Supply with Pixel Extender'''
-In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allow the ground between your lights and controller to vary up to ± 7Vdc. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
+In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allow the ground between your lights and controller to vary up to ± 7Vdc. By far this is one of the best methods to drive strings. It will always work at any distance, the input to the display element is an Ethernet cable and power is through an extension cord. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
 [[File:Wiring_Local_Pixel_Extender_.PNG|600px|Left]]
@@ Line 44: / Line 44: @@
 V = 1.25 amperes
 V = 0.625 amperes
 V = 0.417 amperes
 V = 0.313 amperes
 The Ethernet jacks are rated at 1.5 amperes, and normally two pins are used. Nominally for commercial equipment the connectors are derated by 15 percent to 3.0 x 0.85 = 2.5 amperes. This would be the peak current through the cable.
 [[File:Wiring_POE.PNG|600px|Left]]
@@ Line 59: / Line 62: @@
 [[File:Wiring_POE_Pixel_Extender.PNG|600px|Left]]

@@ Line 1: / Line 1: @@
 The most important part of your show is the wiring. This heavily affects the cost, ease of setup/take down, and how easy it is to fix problems. It is important that you thoroughly understand wiring, before you choose how you want to layout your show.
-== How Many Pixels? ==
+== Basic Recommendations ==
-First, let me list some of the basic guideline that you should follow to ensure that you do not have issues with your hardware. These are guidelines which can be violated, but ensure that you clearly understand what you are doing.
+First, let me list some of the basic recommendations as a starting point for your display.
 ) Only drive fifty 5Vdc pixels without power injection.
@@ Line 10: / Line 10: @@
 ) Do not use ground loops in your power.
 == Wiring Methods ==
@@ Line 27: / Line 33: @@
 '''Local Power Supply with Pixel Extender'''
-In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. This adds additional cost for the buffer/receiver boards.
+In electronic engineering, best practice for signals that go more than a couple feet is to add a differential driver/receiver pair (RS-422/485). These drivers make the signal more immune to noise and allow the signal to be driven further. For pixel data rates (approximately 1MHz), the expected distance is 1000 feet. These also add the benefit of allow the ground between your lights and controller to vary up to ± 7Vdc. There are a couple controllers available with pixel extenders built in. This adds additional cost for the buffer/receiver boards.
 [[File:Wiring_Local_Pixel_Extender_.PNG|600px|Left]]
 '''Power Over Ethernet'''
 [[File:Wiring_POE.PNG|600px|Left]]
 '''Power Over Ethernet with Pixel Extender'''
 [[File:Wiring_POE_Pixel_Extender.PNG|600px|Left]]