Very long digital led strip ...

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peterpan69
 
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Very long digital led strip ...

Post by peterpan69 »

Hi,

We have an huge project, in a brand new building we want to made one digital led strip on each levels (6) on vertical position near the elevator door for mark the elevator level
when it's on move.

For each level an 2.3 meters segement of led strip x 6 = 13.8 meters x 32(led) = 441 pixels .....

Of course we want to made 6 lengths of led strip connect together by wiring and powered by an Arduino Mega, could you think we could use only one power supply on the middle of this segments ?

Do you think we are risk to lost RGB power signal between the lengths ?

Warmest regards.

Peter

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adafruit_support_bill
 
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Re: Very long digital led strip ...

Post by adafruit_support_bill »

could use only one power supply on the middle of this segments ?
You could probably get by with one power supply in the middle of each 2.3 meter segment. You might get a little fading toward the ends. It would be better to feed power from both ends, or V+ to one end and GND to the other.
Do you think we are risk to lost RGB power signal between the lengths ?

How much wire length is between segments? If it is a meter or more, you may need an extra "repeater" pixel.

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Franklin97355
 
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Re: Very long digital led strip ...

Post by Franklin97355 »

If this is for a permanent installation I would consider a driver micro at each floor with communications between them and also power at each floor. Could you draw up something to show us your idea?

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peterpan69
 
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Re: Very long digital led strip ...

Post by peterpan69 »

Thank's for your quick answers :-)

In attachement little drawing of the idea.

By "driver micro" , you mean an Arduino by floor ?

Peter
Attachments
6 sens principe.jpg
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adafruit_support_bill
 
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Re: Very long digital led strip ...

Post by adafruit_support_bill »

Your diagram does not indicate the length of the wires between floors.

At minimum, you would need to supply power to the center of each segment of strip. Pixels much more than about 1 meter from your power feed will start to dim noticibly. By 2 or 3 meters, they may start to malfunction due to the voltage drop.

Also, yo need to connect your controller to the start of the strip. If you connect to the middle as shown it will only control the pixels downstream from the connection point.

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peterpan69
 
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Re: Very long digital led strip ...

Post by peterpan69 »

Ok I estimate the wiring between strip to 0.8 meter.

I have make correction to the drawing with your suggestions; it's really a big disadvantage to put the power on the middle of each segment :cry:

May really can connect the same PWN output in parallel on the two way of strips ?
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6 sens principe.jpg
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adafruit_support_bill
 
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Re: Very long digital led strip ...

Post by adafruit_support_bill »

it's really a big disadvantage to put the power on the middle of each segment
It doesn't have to be the middle. You could connect it at both ends of each segment if that is more convenient. The point is that no pixel on the strip should be too far from a power feed.
May really can connect the same PWN output in parallel on the two way of strips ?
Digital strips are not controlled by a PWM signal. But the control signal can be connected in parallel to two different strips. In this case the two strips will display identical patterns.

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peterpan69
 
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Re: Very long digital led strip ...

Post by peterpan69 »

Ok by this way I can put power supply in the ceiling empty zone :) what are you think by "not to far" ? (in meter)

I think we put the arduino too in the top ceiling and the start of the strip on the top level.

Ok, that exactly what we want the same patterns :-)

hundred of thank's for your ultra fast answers !

(update drawing :mrgreen: )
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6 sens principe.jpg
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Re: Very long digital led strip ...

Post by adafruit_support_bill »

what are you think by "not to far" ? (in meter)
That depends on how many leds are lit and how bright they are. I try not to go more than about 2 meters without a power feed.

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