</QUOTE>Toroidal Power Transformer
For the most state-of-the-art power delivery available-the custom-built toroidal transformer employed in the TX-DS989 is formed from a single strip of silicon steel, tightly wound in the form of a clock spring and wrapped in copper wire to form a silent, highly stable power supply virtually free of mechanical hum. The use of primary and secondary wiring around the entire core prevents air gaps, reducing magnetic flux, and making this very powerful, high-end unit 40% more efficient than conventional transformers.
High-Grade Isolated EI Transformers
Designed for efficient operation, even under high temperatures, these large transformers provide plenty of power reserves for today's multichannel digital sources.
And it's new meter time! I read this as you hanging a meter set to mA across the secondary. Poof!Actually, you can check up on this rather easily. Using all necessary safety precautions, connect the transformer
to the mains, then connect your multi meter across the secondary and measure its quiescent current
consumption (the current it uses up with no load). Remember that by default, larger capacity transformer will use
more current than a smaller one, and in all cases, you are in the milliampere range, below 30."
That tells you what the magnetizing current and eddy losses are to the best of my knowledge.Using a multimeter to read the magnetising current in the primary will not tell you how reactive the current is and therefore is of little use either.
walker said:The core saturation argument makes no sense to me. If you get a power spike I'd rather have the core saturate to keep the sike out of the secondary rather than attempt to pass it on. The EI core will still EFFECTIVELY saturate as the leakage flux increases during a voltage spike.
The problem with saturation referred to is one of small DC component present in the AC network. This will more readily and asymetrically saturate a toroid or R-core transformer than any other type because they don't have an airgap.
Exactly, taking common local conditions into the consideration as well. Real life if you will.Like most of these "which is best"-type questions the correct answer seems to me: "best for what?"
anatech said:"C" cores anyone? They seem to offer advantages of both types.