The small donuts are 20VA each. 🙂
So, the idea is to fuse each 1000VA donut with 4A fuses on the primary, and 0,1A fuses for each of the small 20VA ones.
And i am planning to load them down and test them, when they are fully built, before connecting them to the amplifiers at all.
But i just want to check if it all sounds reasonable with the fuses, since all the info that i can find about it on the internet is not to be trusted. 🙂 And i am unsure about the what the peak demand of the small donuts actually are in the startup of the amplifiers.
So, the idea is to fuse each 1000VA donut with 4A fuses on the primary, and 0,1A fuses for each of the small 20VA ones.
And i am planning to load them down and test them, when they are fully built, before connecting them to the amplifiers at all.
But i just want to check if it all sounds reasonable with the fuses, since all the info that i can find about it on the internet is not to be trusted. 🙂 And i am unsure about the what the peak demand of the small donuts actually are in the startup of the amplifiers.
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100mA it is, slow start
piccolo size, no rush-in currents
if you insist, for better sleep - you can up to 125mA or even 160mA - both will go if something wrong
full blast approach could be relay (faaat one) powered with small Donut PSU, firing up mains side of big Donut
or, even better - but Mighty didn't tried big ones so can't say is it Kosher or not - proper Solid State relay for big Donut mains, powered with small Donut PSU
no biasing voltage, no juice in main rail
piccolo size, no rush-in currents
if you insist, for better sleep - you can up to 125mA or even 160mA - both will go if something wrong
full blast approach could be relay (faaat one) powered with small Donut PSU, firing up mains side of big Donut
or, even better - but Mighty didn't tried big ones so can't say is it Kosher or not - proper Solid State relay for big Donut mains, powered with small Donut PSU
no biasing voltage, no juice in main rail
Right now I am thinking relay with CL60 inrush brakes for each of the bigger donuts. Controlled from the gate voltage donuts regulated voltage. Because a power surge on the primary, say a little lightning and thunder, that could easily kill the 100mA fuses long before the 4A fuses closes down the show, and leaves the building. With or without smoke. Just Like Elvis did.
🙂
🙂
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in case of any dilemma, just buzz
in principle, all you need is one diode and one resistor, feeding SS Relay LED side from AUX/Bias PSU of Singing Bush
so, just route regulated voltage to SS relay trigger side and that's it
mains side of SS Relay feeding Big Donut
during power up, reg voltage is established fast; during power off, reg voltage is lasting much longer than juice in big cap bank
in principle, all you need is one diode and one resistor, feeding SS Relay LED side from AUX/Bias PSU of Singing Bush
so, just route regulated voltage to SS relay trigger side and that's it
mains side of SS Relay feeding Big Donut
during power up, reg voltage is established fast; during power off, reg voltage is lasting much longer than juice in big cap bank
Why do i need the diode and resistor? Would it not work okey just by feeding the trigger side of the SS relay with voltage from C5 after the regulator IC1?
Something like This one seems good enough?
https://amzn.eu/d/6jLqQAa
Something like This one seems good enough?
https://amzn.eu/d/6jLqQAa
Okey, sounds good.
Found these with even better price if i order a pair. I need a pair. And these are 25A instead of 10A.
https://amzn.eu/d/4tVDxpV
Found these with even better price if i order a pair. I need a pair. And these are 25A instead of 10A.
https://amzn.eu/d/4tVDxpV
I used them many years back in time. A big advantage is that they turn-on when the mains crosses zero. So a more gently built-up of the current.
A disadvantage is that there is always a little bit voltage drop at mains side (compared to a good mechanical contact).
My LSB's use external SMPS's. Those also have a soft start circuit. It is a combination of a "CL-60 like NTC" and then a mechanical relay. The mechanical relay will short the NTC when it has done the job. Then no voltage drop or burning of energy during operation in NTC and the NTC will cool down so ready for a "re-trigger" if suddenly drop-out of mains voltage. In principle the mechanical relay could be turned on at same same as the PSU as there will be a short "natural" delay from the relay solenoid gets voltage to the contacts closes (from memory the SMPS just use a parallel capacitor on solenoid voltage to have a short extra delay). When NTC has taken the big inrush the contacts of the relay will have an easy job (not burned by the large inrush current).
A disadvantage is that there is always a little bit voltage drop at mains side (compared to a good mechanical contact).
My LSB's use external SMPS's. Those also have a soft start circuit. It is a combination of a "CL-60 like NTC" and then a mechanical relay. The mechanical relay will short the NTC when it has done the job. Then no voltage drop or burning of energy during operation in NTC and the NTC will cool down so ready for a "re-trigger" if suddenly drop-out of mains voltage. In principle the mechanical relay could be turned on at same same as the PSU as there will be a short "natural" delay from the relay solenoid gets voltage to the contacts closes (from memory the SMPS just use a parallel capacitor on solenoid voltage to have a short extra delay). When NTC has taken the big inrush the contacts of the relay will have an easy job (not burned by the large inrush current).
Yea, there is always various compromises to be made. Part of the fun. 🙂
SMPS vs. Linear
Mechanical vs. SS
NTC vs. Hard Copper Wire 😎
In my Aleph J:s i gain 1 volt in total over the positive and negative rails, on the secondery by bypassing the CL60s with a manual switch after startup. While the switch still is fresh…
Well. Is it worth it? For one volt? Maby. Anyways. Its fun. 🙂
SMPS vs. Linear
Mechanical vs. SS
NTC vs. Hard Copper Wire 😎
In my Aleph J:s i gain 1 volt in total over the positive and negative rails, on the secondery by bypassing the CL60s with a manual switch after startup. While the switch still is fresh…
Well. Is it worth it? For one volt? Maby. Anyways. Its fun. 🙂
