from my experience noise is not a problem as long as you avoid crossing other high electrical lines in the house. if you want if you have weatherized CT’s (or make the ct weatherized) you can put your CT’s out side the house and run a the cat5/6 from there directly . the most important thing to eliminate noise is to maintaining the twisted pair of the cat cable and I bundle up the pairs so that the line drop is reduced
Actually, crossing them is what you want to do, if there’s no other choice. (at a 90° angle) What you want to avoid is running them in parallel with the mains wiring. Of course, the best thing to do is route them away from the mains wiring, but that’s not always possible/practical.
yeah I really meant avoiding high power lines altogether or maintaining some distance from them 
if you want there is s Robin’ diverters or you can use my version based on the oem’s tx shield and an uno ( preferable wemosD3) which also does multiple SSR dumps as well, but can also configure to handle multiple relay loads as well which in the summer for me it turns on my air conditioning, my electric utility car charging and now my recently added electric car ( a chevy volt - as I live pretty remote and there no infrastructure for pure electric cars out here)
You folks are great.
Stephen, I just found your post about extending CT’s, I’m going to use two cat5e UTP that are buried in PVC all the way to the container (I didn’t know UTP was an option before today). I’ve got five cables running out there to the container, and I only need one to get internet service out there, so borrowing two of the five will not cause issues. Can I simply combine all eight conductors from one “cable” to act as a single conductor, or should I use four from one cable and combine those with four from the other cable? I assume the second method will reduce noise even more, but that’s just an assumption, so guidance is appreciated.
I will have to run the cables parallel to the primary supply lines into the house because they will be in the same 3” conduit that leads to the attic from the main breaker panel outside the house (yes, for some odd reason, here in AZ and also in many parts of CA, the panels are outside the home - I don’t love it, but I’ve not owned a home in either state with the primary box inside the home). From that point onward, I can keep the two cables away from other sources of interference / induced current.
Background: I have five cat5e runs leading to the container from the edge of my home simply because the dirt in arizona is difficult to dig up (when it’s dry, the soil is almost like rock - check out caliche to see what I’m talking about) , so I rented a trencher and if I was going through all that trouble, I wanted to have extreme redundancy in the event one of the cables failed, I’d have plenty of spares to leverage. That’s why I can steal two of those UTP cables for the CT’s.
Thanks
as I mentioned earlier it is the twisting of the pairs that reduce the noise. I would only try for now one cable I am sure it will suffice. if you are not familiar with cat five cable twisted pairs consist of a solid colour wire and a striped wire of the same colour . there are green/ green stripe, orange/orange stripe, blue/blue stripe and brown/ brown stripe just put together all the solid colour wires together as one lead and all the stripe wire together as the other lead for the CT… the cable itself should have enough redundancy as it has 4 separate strings of wire in the one cat cable if you want to do two cat cables you still have to put all the solids together and all the stripe wires together from both cables to reduce noise
I’ll run both to the box, but initially connect only one of the cat5 cables. I’ll let you know if everything works as expected. It’ll have to wait for the weekend.
Thanks again
I must emphasise, don’t do that. If I understand you correctly, it could make it a lot worse, not better. As Stephen says, the noise immunity comes from the twists - in effect each half-twist is a loop that picks up interference - and the next half-twist picks up the same but in the opposite sense. So the interference cancels itself.
If you do use two cables, you’re likely to make one big loop that will pick up loads. Use just one. Cat 5 cable loop resistance is ≤0.188 Ω/m, so using even only one pair, you’ll have a series resistance of 14.1 Ω. Depending on your c.t., I doubt that this will worry you. (Two pairs in parallel will reduce it to 7.05 Ω, etc.) But you, or rather your GTI, is really only interested when the current is close to zero anyway, so the volt drop arising from the cable resistance won’t matter, because it too will be close to zero anyway. So while I don’t think there’s a need to use all the pairs in one cable, it won’t cause a problem if you do.
I have it working with six CT clamps and six separate wires running 320 feet (about 97 meters)
I was not able to run the wires through my attic, not because of any interference, but because I was unable to access the far corner of the house to run those attic wires into the distribution panel.
When I gave up on that approach, I rented a trencher (Ditch Witch) from Home Depot ( like Kingfisher if you live in Europe) and trenched 310 feet (the excess cable brings that to 320 feet) and picked up direct burial CAT6 ( Cat6e Shielded Ethernet Cable 1000FT Outdoor Direct Burial Gel 23AWG Pure Copper) on Amazon. I twisted the 4 striped conductors and the 4 solid conductors together giving me two conductors per cable run and 12 conductors total (six cable runs x 2). Each CT has two conductors which were connected to the two conductors in the cat6 cable and then connected at the other end, to the small connector on the Grid Tied Inverter. Six cable, six CT’s and six inverters. I’m told I can run more than one inverter from each CT, but I’ve not tried yet.
It works perfectly, the inverters pick up the CT signal a few seconds after they come on-line each day. 3 of the inverters are on L1 and the other three backfeed L2 - each shows approximately the same current within about 8 watts - which seems pretty good for something so cheap.
I appreciate the helpful guidance from everyone.
1 Like