Today I took a old Pa toroidal transformer it was 1kw dual 65 volt, I removed windings so it became dual 32 volt, I need it for a simple killer amp which requires 45 volt.
My question is, what about the toroids current rating ? Does it stay the same ?
By the way I saved the windings they are 1.5 square and will do nicely as power supply cabeling.
My question is, what about the toroids current rating ? Does it stay the same ?
By the way I saved the windings they are 1.5 square and will do nicely as power supply cabeling.
The core will be having an easier job but since you didn´t increase wire diameter/section current rating remains the same.
Now IF you use the wire you pulled 2 wind two **exact same** turns secondaries and put them in parallel with original ones, yes, you will double current capability and restore full 1kW rating.
Just written as reference, not very practical to do.
Now IF you use the wire you pulled 2 wind two **exact same** turns secondaries and put them in parallel with original ones, yes, you will double current capability and restore full 1kW rating.
Just written as reference, not very practical to do.
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Yes, of cause. It is a direct proportionality.
🙂 But if we will calculate it very pedantically then we may possibly see that the less the wire (the less layers) - the easier to dissipate a heat from inner layers. So, if it may now have a bit (1-5% 🙂 ) better possibility to dissipate a heat. And so it now has not 500 VA rating, but possibly 505-525 VA rating 🙂
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Yes that makes sense, as of now there's just one layer of secondary, still nice and tight, I looked at some formulas and calculations and quickly discovered it was above my head.
Well 500 watt roughly is great for my two greg ball boards.
Thanks again for clarification, that's the great thing in this community.
Well 500 watt roughly is great for my two greg ball boards.
Thanks again for clarification, that's the great thing in this community.
I'm considering makes a new secondary that delivers 12 volt ac for running protection board, I have some spools of thin enameled wire, it will save space and money, and its quite fun and true DIY,.
Since I'm no math genius I wil make 10 windings and measure that voltage, and multiply it up
Since I'm no math genius I wil make 10 windings and measure that voltage, and multiply it up
That is usual (and quite smart) way to do it. Of cause we may make some calculations to find numbers but there is a strong dependence on an actual core material permeability. So it really is much easier and a bit more accurate to do it exact as you say - measure woltage of 10 winds (or '10 turns'? I'm not sure about right term).
Hey, that´s tried and true state of the art.
In fact, IF you counted exactly the turns you unwound and divide lost voltage by them, you already have the answer 😛
@Vovk Z : "turns" is more common but in this Forum if you say "winds" everybody will understand you.
6 month ago I bought a big job lot, 20 meter 60a litze, 40 premade short ground litzes like on pic, and a few hundred heavy duty cable shoes, it comes in handy often, and was cheap.
I think they're used in large industrial power cabinets
I think they're used in large industrial power cabinets
Motor repair shops usually have litzes as they use them for the brushes.
Electrical shops also have them used for grounding cabinets.
There is a company nearby who makes them.
Cabo e Tranca de Cobre – Edgar Praca
Onetime I needed some brushes for a disco lighting jig. I was using motor carbon brushes and they got extremely hot.
I can tell You, carbon brushes are used for high speed. For slow speed You need metalized brushes.
Electrical shops also have them used for grounding cabinets.
There is a company nearby who makes them.
Cabo e Tranca de Cobre – Edgar Praca
Onetime I needed some brushes for a disco lighting jig. I was using motor carbon brushes and they got extremely hot.
I can tell You, carbon brushes are used for high speed. For slow speed You need metalized brushes.
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I checked my closet and found this beast, it has some for me not usable voltages,
Dual 65 volt 7 amp , and dual 77 volt 0.25 amp, plus an auxiliary dual 15 volt 1 amp.
Around 2kw in total. 22 centimetres diameter, 8 cm high.
Funny voltages I guess the dual 77 volt were for Vas section.
It could be very useful if it became dual 40 volt instead, and loose the 77 volt turns.
It's a real money saver toroidals are not cheap.
Okay I didn't think about the molded epoxy core, might get difficult to remove without damaging turns
Dual 65 volt 7 amp , and dual 77 volt 0.25 amp, plus an auxiliary dual 15 volt 1 amp.
Around 2kw in total. 22 centimetres diameter, 8 cm high.
Funny voltages I guess the dual 77 volt were for Vas section.
It could be very useful if it became dual 40 volt instead, and loose the 77 volt turns.
It's a real money saver toroidals are not cheap.
Okay I didn't think about the molded epoxy core, might get difficult to remove without damaging turns
Attachments
That's just a tinned braided copper strap, nothing to do with Litz wire which has individually insulated strands.
Today I started to lower voltage on the big toroid shown, I removed some dual 77 volt turns I did not have use for, they were also low current approximately 1 amp, as shown in pic that are the rest, 65 volts I would like to lower to 45 volt, my problem is the primary, there are two, and because I have 230 volt I put them in series, I connected them to my vario in order to measure the actual volts in secondary, but it draws alot of current as if it is shorted, is the reason the size of that thing?. Am I not able to saturate the core or is there indeed a short ?
Primarys are 0.4 ohm dc.
Rick if you were closer you'd be welcome.
Primarys are 0.4 ohm dc.
Rick if you were closer you'd be welcome.
