.. or maybe it's all in my head?
"ba-dum-tss*
Sorry, I'll see myself out..
Seriously though. Last week I bought two Toroidy TS1200 (2x42V) audio grade 1200VA transformers and when I got the shipping notice a few days later, I noticed that the weight was 15,9kg, which doesn't jive with the 8.5kg per transformer specified by Toroidy. 15,9kg including packaging.
I thought it highly unlikely that the weight DPD used could be that much off, and suspect it's actually calibrated to within a few grams at the most.
That got me curious so I measured and weighed two other Toroidy transformers, TS600 (2x40V) which unsurprisingly is 600VA. They're somewhat smaller and weighs less than specified, almost 7% less in weight and about 4% and 6% less in diameter and height respectively.
Today my 1200VA's arrived and were measured and weighed. I weighed the package upon arrival and my weight is in agreement with the DPD one, 15,9kg. 7.5kg a piece, which is a almost 12% less, but the dimensions are only a bit smaller, at about 2% and 1% in diameter and height respectively.
Then it struck me why. Toroidy has three price ranges within each VA-rating, depending upon secondary voltage(s); <50V, 55V-100V >100V. All three specifies the same diameter, height and weight within each VA-rating.
It's just the amount of copper, the core is the same size within each rating and the number of windings (depending on secondary voltage) and gauge that varies (within a given VA-rating). Right?
Nottin' wrong with my junk, ey. I'm surprised by the close to 12% discrepancy though but I guess that's just the way it must be, likely also across different manufactures. Right?
"ba-dum-tss*
Sorry, I'll see myself out..
Seriously though. Last week I bought two Toroidy TS1200 (2x42V) audio grade 1200VA transformers and when I got the shipping notice a few days later, I noticed that the weight was 15,9kg, which doesn't jive with the 8.5kg per transformer specified by Toroidy. 15,9kg including packaging.
I thought it highly unlikely that the weight DPD used could be that much off, and suspect it's actually calibrated to within a few grams at the most.
That got me curious so I measured and weighed two other Toroidy transformers, TS600 (2x40V) which unsurprisingly is 600VA. They're somewhat smaller and weighs less than specified, almost 7% less in weight and about 4% and 6% less in diameter and height respectively.
Today my 1200VA's arrived and were measured and weighed. I weighed the package upon arrival and my weight is in agreement with the DPD one, 15,9kg. 7.5kg a piece, which is a almost 12% less, but the dimensions are only a bit smaller, at about 2% and 1% in diameter and height respectively.
Then it struck me why. Toroidy has three price ranges within each VA-rating, depending upon secondary voltage(s); <50V, 55V-100V >100V. All three specifies the same diameter, height and weight within each VA-rating.
It's just the amount of copper, the core is the same size within each rating and the number of windings (depending on secondary voltage) and gauge that varies (within a given VA-rating). Right?
Nottin' wrong with my junk, ey. I'm surprised by the close to 12% discrepancy though but I guess that's just the way it must be, likely also across different manufactures. Right?
I think you may have issues with arithmetic😀
Toroidy specify 7.2Kg ??
http://img.toroidy.pl/kk_eng/TS1200.pdf
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Hehe the custom toroids (not toroidy) I’m looking to order won’t be 1200VA but in the order of three power toroids and eight 3H chokes.. so probably about the same mass 🙂
Seems most suppliers use cores with a range of windings.
Seems most suppliers use cores with a range of windings.
Ideally for the same VA the copper is the same weight. For twice the voltage you draw it out twice as long and half the area.
High voltage (hundreds) at low VA figure-out to impossibly thin, so mass/VA is a bit more (a lot more at KV).
High voltage wire will also carry more insulation. We usually neglect the weight of varnish or even poly, but at thousands of turns it adds-up in bulk and weight.
Very high current wire is too thick to wind easy or tight. It may be wound in two smaller strands.
Still, it's not clear to me why 84V 1200VA would be anything special--- oh, you mean that 10V 120A might weigh more? Because 120A wire is like rebar?
Math/simulators give you impossible numbers, such as 1.22897646 mm diameter, etc. , then you go to your supplier who says : "I have 1.20 mm wire, next size is 1.25 mm, pick one" 😀
That´s the difference between Engineering and Physics.
"Ok, ok, I get it ... but then you pick next higher value, isn´t it?"
Usually yes, but sometimes you have to go the other way.
Practical example and I DO wind transformers for own production , thousands of them: my bread and butter 100W Guitar amp PT uses 0.40mm diameter primary, 0.80mm secondary by design, and I typically use 0.45 and 0.85 mm diameter, "next higher up", our Euro/Metric based system offers them in 0.05 mm increments (in smallish diameters).
BUT nowadays Distributors often carry Brazilian made wire, which uses AWG , so no exact matching possible, except by chance.
And what is *today* being sold as 0.45 and 0.85 is actually slightly thicker (distributors also pick "next higher").
Since I fill cores to the brim, minimizing losses, now I sometimes have copper dangerously close to sharp edged EI laminations with risk of scratching/shorting them, a mess and very dangerous, so I HAD to "downgrade".
Mind you, still above theoretical values, only not as much as before.
So a 2021 100W PT is slightly lighter than,say, a 2017 one.
Your currently made one can very well be somewhat lighter than the one they weighted when writing that catalog or Web page ... as long as it meets *electrical*specs, and I´m certain it does (Toroidy is a serious firm), you are definitely covered.
That´s the difference between Engineering and Physics.
"Ok, ok, I get it ... but then you pick next higher value, isn´t it?"
Usually yes, but sometimes you have to go the other way.
Practical example and I DO wind transformers for own production , thousands of them: my bread and butter 100W Guitar amp PT uses 0.40mm diameter primary, 0.80mm secondary by design, and I typically use 0.45 and 0.85 mm diameter, "next higher up", our Euro/Metric based system offers them in 0.05 mm increments (in smallish diameters).
BUT nowadays Distributors often carry Brazilian made wire, which uses AWG , so no exact matching possible, except by chance.
And what is *today* being sold as 0.45 and 0.85 is actually slightly thicker (distributors also pick "next higher").
Since I fill cores to the brim, minimizing losses, now I sometimes have copper dangerously close to sharp edged EI laminations with risk of scratching/shorting them, a mess and very dangerous, so I HAD to "downgrade".
Mind you, still above theoretical values, only not as much as before.
So a 2021 100W PT is slightly lighter than,say, a 2017 one.
Your currently made one can very well be somewhat lighter than the one they weighted when writing that catalog or Web page ... as long as it meets *electrical*specs, and I´m certain it does (Toroidy is a serious firm), you are definitely covered.
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Have you asked the wife to measure it for you to confirm?
Apparently when I measure my toroid transformer, I overstate the measurements...
Apparently when I measure my toroid transformer, I overstate the measurements...