Max node distance and total string length

[injury]

I've done a bit of forum searching and have seen the 6' limit between nodes mentioned (I assume that's related to the data signal drop off from the SSC and not the power since that seems to be a further limit considering the 100' cat 5 patch cable in the video). In calculating some parts to get and maximizing budget I was wondering if there was a max string length to watch out for as well after the SSC. Or some kind of staggered drop off if planning on multiple 6' spaces. In general spaces I'm thinking of will be less than 6' but I think a limit to watch out for over all would be helpful.

Example of what I am getting at would be 5 nodes spaced at 6' and also 6' from the SSC would be 30' which is almost approaching the length of a stock 128 node string, so I wouldn't forsee a problem. However, if one was to take a 128 node strand and have a 6' space every 8 nodes then they'd have a 96 foot long string which would be over double the stock length. Provided that strand plus its patch cord from the hub wasn't too long power wise, would it likely run into data signal issues towards the end of the line? 

[RJ]

Your misunderstanding the limitation. It is not of the total length althought this could be issues also if you made a string 100 ft long for say.

The issue is form ssc to first node/ from each node to each node. The data gets regenerated at each node so the limit is from any device to the next device on the string.

The data up to the point of the SSC is not near an issue as it can run 1000 ft likely with no problem. It is once it is converted at the SSC to the data the nodes use. You must stay under around 6 ft and less if you can to ensure the data stays acceptable to the next node.

The cat5 length is an issue related to power voltage drop. the less nodes on a SSC the farther you can run the Cat5 due to the lower current load. I ran 70 nodes over 100 ft of cat5 with no issue. So you need to keep this in mind also. If you run modules (more current) or longer than this then you will likely have to lower the lenght of cat5 you use. I believe you can run 128 standard nodes over 50ft of cat5 with no issue but some of the others here that get out of the workshop more than me might be able to give us some real tests of what they found.

RJ

I hope this clears it up for you.

RJ

[sielbear]

One question / observation...

I understand the voltage drop limitation between the SSC and the hub.  One thing I'm fuzzy on is if the passive hub could be used to extend that length.  A real world example is that I have a fairly tall two-story house.  Murphy's law states that I will have an SSC at the very peak of the very top of my roof, and getting a cable to it is probably a 50' endeavor from the ground.  Could I take this wonderous little passive hub, run perhaps 50 feet of data (cat 5) and 50 feet of dedicated SPT2 power feed to the passive hub, and place that passive hub is some water-protected enclosure at my gutters.  Then, could I run another 20 feet one direction to my 128 node string and and another 50 feet in a different direction to my second 128 node string high along the roof line.  My total run is then 70 feet and 100 feet respectively from the main hub in the yard. 

Does that make sense?  I was doing the math of the voltage drop, and I agree that 128 nodes, I don't know how much over 50 feet you want to push that power given the current consumption of the 128 node strings. 

[rrowan]

The passive hub does NOT get power from the cat5 input. It has a separate 12 volt connector on it to power the cat5 outputs.

Rick R.

[sielbear]

Yes, I did see that.  I'm wondering, if because power is supplied via a dedicated external cable (and in my case much larger gauge cable), that would seem to provide less voltage drop and greater current carrying capacity than the 24 awg cat 5 cable for the runs direct from the hub to the SSCs. 

[rrowan]

I believe its a safety feature. If power was drawn from the cat5 cable the cable could over heat, short out and be a bad thing

Rick R.

[RJ]

Yes it could. It can not make the distance between nodes of a string longer but it could help with this. At 50 ft your likely fine anyway.

RJ