"It´s common that during commissioning operation guys do many starts and nothing happens.", but actually things do happen, you just don't notice. The high temperatures reached at consequtive start-up's eat away the lifetime of the insulation and the rate of deterioration goes exponentially with...
Thanks kenvlach, I
take it that I can use
the braid as before,
without worrying about
increased brittleness.
NSV
PS What happens to the
text editor in this
thread? I can see only
the left half of the
page
A 0,25mm copper braid consisting of 0,08mm strands is heated to 220°C for 35 minutes which causes the surface to take a golden hue.
The material feels the same, but still I would like to know what causes the color change and if it influences the ability to bend and withstand vibrations.
NSV
Well here's one more on the same subject.
This copper braid is 100 mm long and pretinned for about 10 mm in each end. When I put it into an oven at 220°C for 30 minutes it turns golden.
Again, being more electrical than material, I have to guess wildly that tin is migrating over the surface and...
I live in a small European country where a bicycle is a means of transport rather than a toy. I'm constructing a dynamo to build into the bike's front wheel to supply a small white LED headlamp. I use ø19x5mm Nd-magnets from scrapped tweeter loudspeakers.
NSV
It's a bit complicated to remove the enamel. A torch does not remove it before the aluminium melts, even though we use thermoplastic enamel and we would prefer to use thermosetting for better stability.
But that bit about the laser was interesting. Where do you buy lasers?
Thnx for the help.
I had a typing error - the strands are 0.08mm and not 0.01mm, but still they are very fine and I suppose the finer the more readily they dissolve.
The temperature is indeed very high. The process solders a 0.12mm insulated aluminium wire to the braid and the high...
Ehrr - phase diagram - hrrm, afraid I'm more electrical than material so I can't answer that.
According to the manufacturers declaration for the automotive industry the solder is composed of 99.28% Sn, 0.7% Cu and 0.02% Si. There could be trace amounts of other materials in concentrations too...
We have a proces where we dip solder a 0.1" lead wire made as a braid of 0.003" (approx. AWG 40) copper strands. Apparently the copper shrinks or disappears in the process.
Could it be that the very thin strands simply alloy with the tin to bronze and are dissolved in the tin bath even though...
A delta configuration has no connection to ground so the voltage to ground is completely arbitrary depending totally on the impedance of the measuring instrument and the leak resistance (usually Megaohms) and -capacitance. The reading could come out with anything between 0 and 480V.
NSV
Most often transformers are used to reduce the high voltage at which it is delivered from the power plant to a more modest level which can be used by the consumer. In that case there is not much doubt what is primary and what is secondary.
But then consider any power plant, eg. a wind turbine...
Thanks for your reply, Mike - in what way were you disappointed with ultrasound?
Even the gentlest abrasion is death to a 0.005" wire and I'm concerned about the ultrasound ripping it apart.
We use the same tin bath to strip and solder. Perhaps this is a wrong solution - better to have a hot...
I'm new to Eng Tips, so I am not sure which forum to ask - hopefully you can help or redirect me.
Soldering of aluminium is critical and diffiult compared to copper because of the very inert layer of aluminium oxide that immediately forms when the metal is exposed to air.
In our production we...
