The turns on a pair of paralleled secondary must be IDENTICAL.
This can be assured with a bi-fillar wound secondary. and should be measured by series connecting the two secondary out of phase and checking that zero Vac is emitted.
Then you know you can parallel the two equal voltage secondaries.
Transformers that are not specified as bi-fillar wound will have normal tolerance on the turns and in general will have different turns and thus different voltages on the secondaries.
Different transformers are guaranteed to have different turns on at least some of the windings.
DO NOT parallel different transformers.
If you have two single secondary transformers, you can series connect the secondary windings with a common terminal at the junction.
or
you can rectify and smooth each output and then series connect at the DC side creating a common terminal.
AC? or DC? or something else?
Do you want us to guess?
This can be assured with a bi-fillar wound secondary. and should be measured by series connecting the two secondary out of phase and checking that zero Vac is emitted.
Then you know you can parallel the two equal voltage secondaries.
Transformers that are not specified as bi-fillar wound will have normal tolerance on the turns and in general will have different turns and thus different voltages on the secondaries.
Different transformers are guaranteed to have different turns on at least some of the windings.
DO NOT parallel different transformers.
If you have two single secondary transformers, you can series connect the secondary windings with a common terminal at the junction.
or
you can rectify and smooth each output and then series connect at the DC side creating a common terminal.
what is this?
AC? or DC? or something else?
Do you want us to guess?
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thanks-----
i have 2 transformers—–same type—–15 v 6a —each———made by same manufacturer-- i join the 0 v of each to make dual rail supply of 15-0-15 v 6a --ac--for amplifier
--The turns on a pair of paralleled secondary must be IDENTICAL----i guess they are same as made by same manufacturer-------
now what do you think can it be done without any issues ?
i have 2 transformers—–same type—–15 v 6a —each———made by same manufacturer-- i join the 0 v of each to make dual rail supply of 15-0-15 v 6a --ac--for amplifier
--The turns on a pair of paralleled secondary must be IDENTICAL----i guess they are same as made by same manufacturer-------
now what do you think can it be done without any issues ?
the turns on a transformer are subject to the manufacturer's tolerances.
those tolerances are on both the primary and secondary windings.
You cannot rely on different transformers having exactly the same voltages.
When you connect a pair of windings in series with a common terminal, it does not matter that one winding may have a slightly higher voltage.
When you connect in parallel, it becomes absolutely critical that the output voltages are identical !
those tolerances are on both the primary and secondary windings.
You cannot rely on different transformers having exactly the same voltages.
When you connect a pair of windings in series with a common terminal, it does not matter that one winding may have a slightly higher voltage.
When you connect in parallel, it becomes absolutely critical that the output voltages are identical !
if the transformers both made by same manufacturer @16 v 6a----you are saying they will not give same+/- output-----
i have 2 queries------
1-------assuming they do give 16-0 and 18-0 v---but dual rail tda amps donot care about same voltage ?
2--------if i connect series then will i get 16-0-16 v ac at 6a ?
i have 2 queries------
1-------assuming they do give 16-0 and 18-0 v---but dual rail tda amps donot care about same voltage ?
2--------if i connect series then will i get 16-0-16 v ac at 6a ?
Don't join the "0V". Wire in series so they give opposite polarity.
The plan below will work.
If the transformers are not *exactly* matched, they will not share the load exactly equally. The voltage is the turns-count. Do the low-pay workers count exactly? Often they do (or a machine does). Sometimes they are off-by-one. This would be about 0.1V difference. We expect about 1v of sag/regulation. So a near-match pair may split the load 45:55 instead of 50:50. If you have an exact load that runs all day, I might worry. Audio amplifiers are light load except in bench-testing, which is usually not a long-term condition. I would not worry. Especially in DIY where if it smokes, you can build something different.
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