Author Topic: Power Supply Question for Strip Lights  (Read 310 times)

Offline MGoBlue102

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Power Supply Question for Strip Lights
« on: August 15, 2018, 12:53:52 PM »
Quick question I hope for anyone that may have already dealt with this but my question is related to power supplies being attached to my strip lights.  I plan on running a strip light that is approximately 9 meters.  It will consume approximately 153 watts.  I have some wonderful inline power supplies at the base my other strips that require less than 100 watts and the power supplies are 100 watt units.  (I haven't actually encountered this same device greater than 100).  For this strip, I was wondering if power flows both ways.  Could I put a 100 watt power supply at both ends of my strip essentially supplying the strip with 200 watts?  Any thoughts?

Offline tbone321

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Re: Power Supply Question for Strip Lights
« Reply #1 on: August 15, 2018, 03:20:38 PM »
You can do that and many do as a form of power injection.  Power does not flow down the lines like the data does.  It really doesn't matter where on the line the power is connected as long as the polarity is correct. 

Offline mac50

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Re: Power Supply Question for Strip Lights
« Reply #2 on: August 15, 2018, 06:59:22 PM »
You can do that and many do as a form of power injection.  Power does not flow down the lines like the data does.  It really doesn't matter where on the line the power is connected as long as the polarity is correct. 
This is true if you are doing injection with the same power supply or 2 that were designed to work together in parallel. My understanding of your question is that you are hooking a different power supply on each end. If the supplies were not designed to work together, it might still work but the voltage regulators in the supplies are independently trying to control the voltage.  Likely to cause problem sooner or later.If your supplies are not made to work together, you can hook one to each end but you should split the +v line (only it and not the -v) in your strip. Since you are using identical supplies, half way would be ideal.

Offline tbone321

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Re: Power Supply Question for Strip Lights
« Reply #3 on: August 15, 2018, 09:14:26 PM »
If the supplies were not designed to work together, it might still work but the voltage regulators in the supplies are independently trying to control the voltage. 


This has been proven to be more fear than fact, especially with this setup.  If you are talking about two high power tightly regulated power supplies wired in parallel at the same point in the string, then there is the possibility of the two supplies fighting each other if the specific voltage each is trying to maintain is not the same as the other but none of that is the case here.  Neither of these supplies are either high powered or tightly regulated and they are on opposite ends of the string.  The voltage drop in the strip should be enough to prevent the supplies from really even seeing each other, especially under load.  In a string, many do cut the positive somewhere mid-string to prevent the supplies from fighting each other but that is not so easy to do in a strip and is usually not necessary.  One issue with doing that in either case is if the first supply fails, the entire string goes out because the data will never get to the second half.  In this situation, one supply should be able to keep the string going to some level until the failed supply is replaced.

Offline Sawdust

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Re: Power Supply Question for Strip Lights
« Reply #4 on: August 15, 2018, 09:51:08 PM »
As others have mentioned, unless your PS are designed to parallel, then do no, period. 

Power supplies on each end REQUIRES separation (unlessed specifically designed.).   Cut V+ (only) at mid point, leaving data and ground intact....this will carry data from first half to second.  Powering second half from other end is ok.
« Last Edit: August 16, 2018, 12:43:21 PM by Sawdust »

 

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