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My thoughts on Cable design.

jsrtheta

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Just to inform you all, my writing skills are zero, I blame my dyslexia and autism for it but it got much worse since the stroke I had , so please forgive me, and cringe less.

I HAVE NOW REMOVED THE UN-READABLE GARBAGE.
Please remove me from this forum Amirm thank you.

No need to explain.

You see nothing but friends here.
 

pma

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Before the thread may get closed I would like to say that it was a good and interesting topic. Please let me continue, as I did a lot of similar work as Colin posted, in my research institute years and also had several publications.

To measure H and B we may use a simple loop probe and the induced voltage will be proportional to H and B as per Fig. 2.

loop_probe.JPG

Fig.1. Simple loop probe

loop_voltage.png

Fig.2. Calculation of induced voltage (reprinted from my article for Slaboproudy Obzor)

Now let's make a simple test. The probe from Fig.1 is used to measure magnetic field radiated from the
1) magnetically shielded power cord
2) unshielded power cord
We will measure loop probe voltage with power cord connected to 230Vac and
a) unloaded
b) loaded with 1500W, resistor load

1a - magnetically shielded cord no load
loopprobe_magshieldcord_noload.png


1b - magnetically shielded cord 1500W
loopprobe_magshieldcord_1500W.png


2a -unshielded cord no load
loopprobe_unshieldcord_noload.png


2b -unshielded cord 1500W
loopprobe_unshieldcord_1500W.png


One may use his own head to calculate radiated H and B from 2b plot and 4cm probe diameter as a homework.

@amirm , before you potentially delete this thread would you please move my post to a new thread. Thank you.
 
OP
Colin James Wonfor

Colin James Wonfor

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No do not move it very interesting.
Did the test cable have a magnetic covering as well. A iron pipe would do. What material was it ?? I tried NeO compound it was the best but I also found it got magnetized then became useless.
Tried Fe,Ni,Co but the best result was odd it was a SrNeCo mix it proved to be best. Then I tried due to cost just SrO compound in the mix the surprise was it was not magnetic i.e. a magnet did not stick but the rejection was very interesting in the BW 10 -500Hz and a peak at 5Ghz the figures are long gone now. The mix was only 5% by weight with bog standard recycled PVC (shit grey colour).
At Norwich Uni I tried with help from Doctor Salmon, liquid N and He. He was the best but the plant was as big as bus. Using 99.999% etc pure Cu.
 

pma

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Nice to see you did not give up, Colin.

The tested shielded cable is flexible, as yours. It is a professional product. More later.

I did read and downloaded your PDF that was attached in post #1. It think you might consider re-posting, as it will be interesting at least to some members, if not for the majority. Please overlook the aggressive posts, it is just a forum.
 

Thomas savage

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No do not move it very interesting.
Did the test cable have a magnetic covering as well. A iron pipe would do. What material was it ?? I tried NeO compound it was the best but I also found it got magnetized then became useless.
Tried Fe,Ni,Co but the best result was odd it was a SrNeCo mix it proved to be best. Then I tried due to cost just SrO compound in the mix the surprise was it was not magnetic i.e. a magnet did not stick but the rejection was very interesting in the BW 10 -500Hz and a peak at 5Ghz the figures are long gone now. The mix was only 5% by weight with bog standard recycled PVC (shit grey colour).
At Norwich Uni I tried with help from Doctor Salmon, liquid N and He. He was the best but the plant was as big as bus. Using 99.999% etc pure Cu.
Great to see your still here Colin!
 
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