Calculating Transformer Fuse

[tomchr]

Or a board made in the western world: https://neurochrome.com/products/intelligent-soft-start

Tom

 

[NIXIE62]

Oh yeah, $189 for such a simple feature. It is more expensive than a transformer.
I made such things cheaply 30-40 years ago and they still work everywhere. My brother's amplifier has one of the first inrush current limiters I built as a student. And it's still in operation every day in his workshop. I did a recap about 10 years ago.

 

[Ghoostknight]

i thought a while about it and i think i will do this:

• small transformer with rectifier and smoothing caps
• one 5V regulator socket for my tps regulator
• atiny10 microchip
• 2 relais, one as passtrough and one to switch the resistor trace off, making it possible to actually switch ON/OFF

so you can switch directly on one spot with a external button hooked up instead of needing to switch 230V externally, this way you also just have one relais in the path, where with a 230V button or a external relay you would have 2 switches in the path... minor detail but why not...
- screwterminals for: 1.power IN/OUT 2. external resistor IN/OUT 3. button IN/OUT 4. led +/-

the thing should work something like this:
(on standby maybe led breathing or something like that)
you hit the switch, the microcontroller closes the resistor relay, waits 3-5 seconds and blinks the led, switches the passtrough relay and makes the led steady, a 1second press turns the device off

maybe its also possible to reserve 1 or 2 gpios for external functions i dont know yet

i think putting all together is quite simple but i have to see, the arduino program for the microcontroller should be no problem