Transformer secondaries are 24Vac, recommended fuses 6.3A slow blow, 25A rectifier, 10.000 µF first cap, 140.000 µF second cap.
The toroid only 300 VA for mono, no inrush current limiter needed.
For raw testing I would like to keep it as simple as possible.
So the obvious question is, can I turn that on without blowing something ?
Does it make sense to put a 5W 0,33 ohms resistor between the caps ? and will it withstand power on surge ?
I could cut the 140.000 down to 120.000
The toroid only 300 VA for mono, no inrush current limiter needed.
For raw testing I would like to keep it as simple as possible.
So the obvious question is, can I turn that on without blowing something ?
Does it make sense to put a 5W 0,33 ohms resistor between the caps ? and will it withstand power on surge ?
I could cut the 140.000 down to 120.000
Hello,
If you make a crc network it will limit the current. You can take a look at the hiraga 20 watt power amp which also uses big caps. Maybe you can try putting two 5 watt resistor in parallel.
Depending on the current flow they will get hot. Lower value the current will be bigger but the charging will be faster.
Most of the time the 6A fuse will blow if something is wrong.
Greetings, Eduard
If you make a crc network it will limit the current. You can take a look at the hiraga 20 watt power amp which also uses big caps. Maybe you can try putting two 5 watt resistor in parallel.
Depending on the current flow they will get hot. Lower value the current will be bigger but the charging will be faster.
Most of the time the 6A fuse will blow if something is wrong.
Greetings, Eduard
The secondaries have about 0.2 ohms, so a little more resistance would limit the current a bit ?
Also I could measure bias at that resistor.
The transformers are a mystery, they measure 15cm x 8cm and are pottetd in plastic, but only 300 VA, that size usually has 600 VA at least.
- you are a bit wrong here, unfortunately. The good news is that the primary current inrush limiter will limit a charging current too. So I would propose to use an inrush current limiter (in the primary circuit) as a universal and quite simple answer to all questions.
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For a raw testing, I would use an NTC resistor in the primary circuit. Something between 3.3R and 10R.
You could think about installing one of THESE inrush current limiters between the 10.000uF capacitor and the 140.000uF capacitor. At power up, when they are cold, these are 50 ohm resistors. Their high resistance limits the rectifier current at power up, to (24*sqrt(2)/50)=0.68 amps. Loooong after power up, when they have heated up to steady state, their resistance when 6A is flowing, is 0.3 ohms.
I was waiting for that question
Because I have them and they look more nice in amplifier than somewhere is storage.
And because I look at them as a kind of battery.
Wrong about what ?
It means it does not turn out the 16A fuse in my home, some 500 VA toroids are able to do that.
Good idea, only I dont have one, need order online, we are in permanent lockdown.
One issue, I can not turn off the amplifier and turn on after short time, need wait to cool down that NTC ?
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