there are two ways to take the power transformer into core saturation:
1. input more primary voltage than it was designed for, i.e. 440vac input into a primary meant for 220 vac, here, even without any loading in the secondary, transformer burns out if not fused properly..
and or
2. load the secondary with more current than it was designed for, net effect is core saturation...
i have seen these two scenarios play out is real life...
1. input more primary voltage than it was designed for, i.e. 440vac input into a primary meant for 220 vac, here, even without any loading in the secondary, transformer burns out if not fused properly..
and or
2. load the secondary with more current than it was designed for, net effect is core saturation...
i have seen these two scenarios play out is real life...
All false. I suggest that you recheck RDH4 and by Rod Eliott's article on transformers
https://sound-au.com/xfmr.htm
Only AV (alternating voltage) and DC matter in terms of a magnetic core transformer.
As for heating resulting from AC loading a transformer, it is caused primarily by Rdc losses and some core loss, depending of the core choice and operating flux density, but NOT core saturation.
Noise resulting from an increased transformer loading IS NOT related to core saturation. Perhaps an exception to this case would be the usage of half-wave rectification, bringing pulsating DC to the transformer windings.
https://sound-au.com/xfmr.htm
Only AV (alternating voltage) and DC matter in terms of a magnetic core transformer.
As for heating resulting from AC loading a transformer, it is caused primarily by Rdc losses and some core loss, depending of the core choice and operating flux density, but NOT core saturation.
Noise resulting from an increased transformer loading IS NOT related to core saturation. Perhaps an exception to this case would be the usage of half-wave rectification, bringing pulsating DC to the transformer windings.
i have seen it happen before....
short the traffo secondaries... with the primary input voltage...
and watch the traffo go up in flames....
but folks do not do this at home unless you have a fire extinguisher on hand...
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Have you ever shorted out a switch or outlet you were working on HOT, and heard the wires rattle around inside the conduit? With that kind of current, they will MOVE around if not constrained. Transformers with even the slightest looseness to the windings will do this when heavily loaded.
I always put a DC blocking filter on the input to my toroidal power transformers. Just a big square 30 amp rectifier bridge and two big caps wired back to back making a nonpolar cap. The schematic is on the web. It’s cheap insurance when using a toroid and it cleans up a little of the hash on the AC power. I’ve never had an Antek buzz yet. Their toroid covers have a plastic feed through for the mounting bolt so you don’t make a single turn short! They also include a square bottom mounting plate you can use or not. You can get their 400va transformer plus a cover for about $100 plus shipping. I always overspec the current rating on my transformers so they run cool all day long.
I’ve never had enough DC on the line to cause issues with toroids. Big ones often give a solid “Brrrrmp” when first turned on - there is a decaying DC term. But when it’s gone it’s gone. Just the normal amount of attention to balance one would want for a high quality tube amp seems to be ok to allow using them for P-P tube OPTs
So far Anteks have been quiet. They run at relatively low flux density at 60Hz/125V. I haven’t had any making an undue amount of noise at heavy load either. The tape may not be all that tight but the windings seem to be.
So far Anteks have been quiet. They run at relatively low flux density at 60Hz/125V. I haven’t had any making an undue amount of noise at heavy load either. The tape may not be all that tight but the windings seem to be.