Transformer Help??????????????

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An 8A AC VA rating transformer can only supply 7A DC from a capacitor input PSU for a short time, but perhaps 3A indefinitely.

You may need to discover whether the 700W is advertiser's watts or engineer's watts.

I'm thinking advertiser it may peak at 700w but I don't think it will do continuous power maybe 500 or 600w but not 700w. This amp runs ten pairs of 2SA1943 & 2SC5200 transistors for output.
 
What makes you say that? The amplifier board I have recommends a Power: AC dual 45 ~ 50V (300W ~ 700W), and a single exchange of about 15V (10W) and the Peak power output 700W mono at 4 ohms. So 700w = about 7 amp draw ac so a 8 amp transformer should do more then the job I am asking of it. So if I am wrong please let me know. It is better to ask a question then trying to guess the answer I don't quite understand.

because i build my own transformers, i know what works...

for your requirement, you have more than enough, i estimate that you have a 1000va traffo there...

do not be trapped in the numbers game, if you have the traffo, just use it...

in the final analysis, it is the load that determines what power is drawn,
the power traffo is there to supply it, and by the looks of it, you got a big big traffo to use....
 
using core area squared times 0.75 gives 711VA.

Now adjust the flux to suit the lamination type/thickness.

711va seems small by the chart I have it would closer to a 1000va

Example This core is [SIZE=+0][SIZE=+0]3.8 x 8 and it is [/SIZE][/SIZE][SIZE=+0][SIZE=+0]924W [/SIZE][/SIZE][SIZE=+0][SIZE=+0]and the core area is ([/SIZE][/SIZE][SIZE=+0][SIZE=+0]30.4)[/SIZE][/SIZE]
I got this example from this web site
Como calcular un transformador de corriente
 
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711va seems small by the chart I have it would closer to a 1000va
If the standard guide gives 711VA for 1T, then the only way to get 1000VA output is to run the core at 1.4T
I believe from what I am being told that good thin laminations can manage this flux.
But the iron used in EI cannot operate at this flux. Expect 0.7T to 1T for an EI and about 1T to 1.6T for Toroid/Rcore/Ccore
 
if you have the traffo on hand,
it is pointless to debate what it can and can not do,
i say just use it....
after all that traffo does not stop delivering power at 701 watts,
read your post again, recommendation is for 300 to 700 watts...
if you are going to ask over and over again, you will never finish that amp...
build the amp and then you will realize that you worried over nothing...;)

Originally Posted by Life is a Enigma View Post
What makes you say that? The amplifier board I have recommends a Power: AC dual 45 ~ 50V (300W ~ 700W), and a single exchange of about 15V (10W) and the Peak power output 700W mono at 4 ohms. So 700w = about 7 amp draw ac so a 8 amp transformer should do more then the job I am asking of it. So if I am wrong please let me know. It is better to ask a question then trying to guess the answer I don't quite understand.
 
if you have the traffo on hand,
it is pointless to debate what it can and can not do,
i say just use it....
after all that traffo does not stop delivering power at 701 watts,
read your post again, recommendation is for 300 to 700 watts...
if you are going to ask over and over again, you will never finish that amp...
build the amp and then you will realize that you worried over nothing...;)

I am committed to using this transformer when I received it I posted the measurements not to question it just to let you guys know the size of it. Now all I am waiting for is the 19 gauge magnet wire I order for I can add the other 15v secondary I need for the amp so far I added a layer of Kapton HN Film Tape to the outside of the transformer then I am going to wrap the 19 gauge magnet wire on top of that.
 
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