So there are all sorts of Indian catalogs availiable online and I was looking through them and trying to determine the amount of copper in the wires based on the spec. Most of the catalogs use AWG, here's an example: The 4A 16/0.20 size, 0.5sqmm is what I'm looking at. So, 16 turns of 0.2mm dia/turn wire. https://en.wikipedia.org/wiki/American_wire_gauge tells me that 0.2mm dia is 32AWG and a single strand supports 7A for 10sec or 10A/1sec fusing current. So obviously he's provided x10 turns or x15-16 turns just to be safe which kind of makes sense for 4A..
The volume of copper in that wire is 28.67gm over 100m and at a price of 712/kg it would cost 327/ and therefore would sell for 624/ (not factoring cost of PVC over 100m)
What I wanted to know was that whole x10 or x15-16 at 4A instead of 7A seems arbitrary so.. is there a way to determine exactly what they are doing wrt wire - any books, reading resources that explain how Turns and twisting affect the calculation? What are the common insulations used?
What a delicious question @veekm !!!!
I think the answers may blow the lid off a massive pricing - marketscam going on in the audio cable industry.
Come on metallurgists, chemical engineers, cable aficionados, industry insiders, let’s hear the facts....is that a whistle we hear?
I do appreciate the value of good quality cables, but A quick query on Google search throws this up: Here are some of the most expensive audio cables currently on the market.
Siltech Emperor Crown - $40,000. This is the most expensive audio cable of all time. ...
What I've kind of learned is that for expensive stuff.. the goal of marketing is to 100% at each step.. so any change to the base price causes x2 all the way through the supply chain. Traders and dealers have absolutely no qualms of x2ing based on what they 'pay'.
Copper wire is actually pretty cheap/affordable at the point of manufacture.. a mere 327/100m/4A16/0.2 but on SP road I would pay x2 at least - never does it fall below that and for online add 30% over SP Road. The logic seems to be.. if 'God' has entrusted him with 100/ Rs of capital, he can sell for 200 easy-peasy - that's his take EVEN if his actual value addition is 10p.
So, as long as there is a small, exclusive group of people who ....no. I can’t do this to my audio compadres.
The prices surely must have something to do with oxygen, purity of Cu, purity of intention, the plastic covering, the weave, conductivity, impedance, resistance, interference, .... sanctity ?
oh hmm.. heh - I'm just trying to understand the mechanics of ordinary wiring - how they calculate the OD of the cable based on the AWG of the inner conductors and such. Sometimes the industry will have a key book or manual that shopkeepers use.. For example.. for vapor deposition on plastic film (Mylar bags) after much googling I found https://www.aimcal.org/uploads/4/6/6/9/46695933/ferrari_and_ataya_abs.pdf but the link doesn't work because someone used their 'influence' probably to have it removed. It was a nice book available for free but some Indian jackasses to do what they do ergo..
Anyhow I'm looking for industry manuals/catalogues/brochures that are informative on boring topics like switches, switchgear, wires, insulation and dielectrics etc
all these refer to Indian standards but I found nothing about the metals and material. Few places it was mentioned as ISI marked cables and color codes. That is all.