Salas hotrodded blue DCB1 build

[AndrewT]

dtes,
how do you measure the internal temperature of a transformer?
How do you know if your duty overheats the transformer?
What does the transformer manufacturer tell you about drawing AC current from the transformer?
What does the transformer manufacturer tell you about drawing DC current from the transformer?
It appears you are completely ignoring what the manufacturer tells you about his own product.

[dtses]

Originally Posted by AndrewT

how do you measure the internal temperature of a transformer?

with a help of infra-red gun it shows about 50-55c on the surface in non ventilated enclosure.

Originally Posted by AndrewT

How do you know if your duty overheats the transformer?

Don't know that actually. The set of IC + Salas reg that I'm feeding requires about 80% of current that is written on the transformer.

Originally Posted by AndrewT

What does the transformer manufacturer tell you about drawing AC current from the transformer?
What does the transformer manufacturer tell you about drawing DC current from the transformer?

well..not much info I found.

Originally Posted by AndrewT

It appears you are completely ignoring what the manufacturer tells you about his own product.

not on purpose, simply learning on practise from experts' advices and info in the thread, hate books

Anyway, I've got your point regarding toroid!
Cheers

[AndrewT]

and the internal temperature is?

max continuous AC current = VA / Vac when feeding a resistor.
Max continuous DC current = VA / Vac / 1.414 * de-rating factor when feeding a capacitor input filter through a bridge rectifier.
The manufacturer will tell you the de=rating factor for that transformer. Expect it to be ~0.7
This results in a max continuous DC current of ~ half the max AC current.

You must check the manufacturer's data on how to use their product.

[dtses]

understood, Sir!

now I have the feeling that I know everything regarding PS

Originally Posted by AndrewT

and the internal temperature is?

sorry, about 50c is with an open lid of the case, ~55 showed after an hour of operating with a closed one.

[AndrewT]

The internal temperature could be at the maximum limit determined by the manufacturer, or below that reliable limit, or worse above that reliable limit.

You have no way of estimating the internal temperature by monitoring the surface temperature.

[BigE]

Originally Posted by AndrewT

and the internal temperature is?

max continuous AC current = VA / Vac when feeding a resistor.
Max continuous DC current = VA / Vac / 1.414 * de-rating factor when feeding a capacitor input filter through a bridge rectifier.
The manufacturer will tell you the de=rating factor for that transformer. Expect it to be ~0.7
This results in a max continuous DC current of ~ half the max AC current.

You must check the manufacturer's data on how to use their product.

Great... my 80 VA transformer is too small for a hot-rod.

[AndrewT]

Originally Posted by BigE

... my 80 VA transformer is too small for a hot-rod.

That is not what post2157 said.

That leaves you with the 80VA 15+15Vac. The maximum continuous output current is ~ 1.3Adc
You will be running the transformer at it's full maximum rating continuously if you draw 1.3Adc from the rectifiers.

1.3Adc is 65times the current consumption of the buffer circuit.
That means you would have 64/65ths of the current throughput of the Salas Reg for "hot-rodding".
Whereas a 80mA DCB1 would have only 3/4 of the throughput as regulator overhead.
That is a mighty big leap into "hot-rodding" territory. Particularly when one considers that 200mA and 600mA are both "hot-rodding" options.

[BigE]

Thank you!

[mjock3]

Andrew, I have a 100VA 15+15, what is the max I could safley run the DCB1 at?

[dtses]

mjock3

1.6A it is I suppose if to recapitulate Andrew's suggestion in post 2163.

btw, what settings do you have now?