Toroid for mains conversion?

" snipped-for-privacy@gmail.com"

** False. The percentage efficiency of similar rated E-cores and toroiodals is the same. ** Makes them preferable in slim, rack style cabinets. However, a U-core transforemer is just as low in height. See pic:

** Cos it is simply NOT the case - pal.

Plus there are many drawbacks associated with toroidals.

..... Phil

Cost, you can wind 10 EI or U cor transformer bobbins at once. ( right off the wire spools ) A toroid can only be done one at a time. (unless the machine can handle more than one) A shuttle needs to be wound for each toroid. toroid winding equipment cost more.

They do offer benefits, but the added cost is not justifiable in most cases.

Cheers

They are less leaky. It stands to reason that any difference, even if too small to consider major, would be in favor of the toroid.

"Toroidal transformers typically are 90 to 95 per cent efficient; whereas E-I laminates have a typical efficiency of less than 90 per cent."

Of course they do not mention anything about mains/low frequency but since they don't mention the frequency dependence I'd assume it is the general case. After all the reason why E-I is less efficient is because of the geometry which is probably frequency independent.

"Martin Riddle"

** Against that are facts like:

1. C-cores come ready to use, instead of a box full of lams to be assembled after the bobbin is fully wound and terminated.

2. C-core winding is very fast, inclding all the layers of plastic wrap.

1. The winding wires can also be used to form the terminations in many cases.

2. No metal mounting frames or bolts need be fitted by hand to assemble the final product.

1. No resin coating or baking in an oven is needed to excluded moisture or make all the lams stick together.

Fact is, that in the majority of VA sizes and styles, a toroidal tranny takes LESS time to complete than E-core types and uses less materials.

..... Phil

This sounds like a much more reasonable answer.

"Dorothy with the Red Shoes on"... "Phil Allison"

** ??????????

** For the same VA rating, percentage efficiency ( under load) can go either way, by small margins.

The subject is MAINS power toroidals BTW.

..... Phil

" snipped-for-privacy@gmail.com" "Phil Allison"

"Toroidal transformers typically are 90 to 95 per cent efficient; whereas E-I laminates have a typical efficiency of less than 90 per cent."

** Complete pile of MARKEING bullshit !!

Lots of it to be found on the web - fool.

So do not use it as FACT !!!

..... Phil

..... Phil

" snipped-for-privacy@gmail.com"

This sounds like a much more reasonable answer.

** Hey listen - DICKHEAD !!!!

YOU are in NO position to judge the answers.

Cos YOU are a know nothing wanker.

..... Phil

Cost

Bob

Switchers.

John

The only toroidal transformers I have seen are in high end low level audio equipment.

Bob

** Then you have seen sweet f*ck all audio gear.

Cos the majority of high powered amplifiers used in pro-audio have toroidal transformers.

.... Phil

'high end' 'low level'

How retarded.

So I'm suppose to listen to some retard who acts like an expert and claim he is an expert just because he wants to be an expert? You have the proof by authority down pat! Don't get me wrong. I'm sure your a genius. This is quite comical. You get all upset cause someone doesn't take your drool as gospel. Your proof humans haven't evolved very far from apes.

" snipped-for-privacy@gmail.com "Phil Allison"

So I'm suppose to listen to some ...

** No need for anyone to simply *believe* anything I post.

Politely ask me for the REASONS and I *will* supply them.

But PITA trolls like you NEVER ask for reansons

- cos they know it will all go right over your head.

YOU do not even know what transformer "efficiency " IS nor how to quantify it nor if it is a variable or fixed number.

So piss off - d*****ad.

..... Phil

"John Larkin" " snipped-for-privacy@gmail.com"

** Aside from the fact the OP's information is WRONG - I suspect he can tell a SMPS from an iron core transfomer PSU.

The Q is why do you see far more E-core than toroidals in commercial equipment, given the oft claimed "efficiency" and size advantage of the latter ?

..... Phil

Co$t.

I see 'em all the time in Rohde & Schwarz test equipment.