pmgodfrey (November 30, 1999 at 12:00 am)

@Sillyzombie666 No!  It's ROBOTS BAKING PIES!

UTubeisSHIT523441 (November 30, 1999 at 12:00 am)

about the price... thats why they use the thick >>aluminium<< strip on the secondary. If they use copper instead, the price will probably skyrocket.. They still use the copper wire on primary though.

mtdeezy (November 30, 1999 at 12:00 am)

Wait... Is that aluminum strip the secondary coil?

ChumpusRex (November 30, 1999 at 12:00 am)

@yourTIV0 It wouldn't be "insanely" expensive. It would be more expensive, sure. However, the cost recovery time is short. Upgrading from Al windings to Cu has a typical repayment time of between 2 and 4 years, due to lower losses, unless the transformer is very lightly loaded. Similarly, for the use of amorphous metal rather than cold-rolled silicon steel, the payback time is also around 4 years.

yourTIV0 (November 30, 1999 at 12:00 am)

@ChumpusRex Actually, Aluminum is a superb conductor for this application. Using solid copper in place of the aluminum would be insanely expensive, and aluminum is a quite decent conductor. In fact, the main lines going in to the load centers of many homes and businesses are aluminum (or copper plated aluminum), anywhere from 3 to 4/0 AWG.

hitachi088 (November 30, 1999 at 12:00 am)

fuck, those thing are made so cheap! aluminum, WTF people!!

frosty956 (November 30, 1999 at 12:00 am)

@ChumpusRex Actually, the magnetic field outside the cross section of the core is very tiny, so the flux cutting the cross section of the sheets is almost zero, so there are essentially no eddy currents in the aluminium sheets. The use of steel cores is ideal, we have to consider cost of materials here, ease of fabrication etc. Even though Al. has a higher resistivity, we can compensate by making the conductors larger, hence the sheets. A modern large power transformer is easily 99% efficient

donnyab (November 30, 1999 at 12:00 am)

that what I NEED for my amp !!!

ChumpusRex (November 30, 1999 at 12:00 am)

Disappointing that people are still making transformer with aluminium sheets. Al is a relatively poor conductor compared to Cu, so increases winding losses. The use of sheets is also sub-optimal, as the large conductor cross-sectional area leads to large eddy current losses (part of the core losses). Finally, on such distribution transformers, the use of steel cores is also not ideal, and the use of metallic glass cores gives much better performance and lower operating costs.