Andy and analogspiceman
Thank you for your replies.
Actually, I am not sure what I was thinking for the path length = Ie!
It should of course be Pi * D where D = (Internal Diameter + External Diameter)/2.
Hence for my figures it is about 71.47mm, so Lm is 71.47m.
Also I now realise that LTSpice has Hc specified in A/m and the Information I found for typical ferrites was 0.2 Oesteds which is about 15.9 A/m. So Hc for LTSpice = 15.9.
I appreciate that there is a lot of variation in ferrite materials, but I am just trying to use a typical one that could be used for a Current Transformer, as I do not know which specific one has been used.
Having clarified the above, I have one more question.
Do you have any knowledge of how the actual VA of the Burden Resistor used versus the VA rating of a Current Transformer affects the accracy of the resuting Voltage?
My thinking is that the higher the VA through the Burden and hence the Current Transformer's secondary coil, the hotter it gets and hence this affects the resulting Voltage as the core's magnetic properties dictate.
Would that be correct or can you offer any more insights and/or provide any links to sources of information about this topic?
Thanks and Regards
Henry Kafeman
---In LTspice@..., <ai.egrps@...> wrote :
Henry wrote:
? ?"I now believe the core of the CT is "ferrite"."
?FYI -- ferrites encompass a whole class of materials, with a widely varying range of magnetic characteristics.? Ferrites are often used as cores for "ferrite beads", chokes, and transformers, and there are many ferrite materials (or "mixes") to choose from.
Andy
