if the fuse holds, what else is there to worry about
are you not building heavy duty classA using only tough components
maybe it also saves on the switch with a film cap on its terminals
well. i was thinking of the stress of the transformer.
the capbank will want to draw a Extreme current to charge in a smal amount of time. at the same time that the transformer is restricted by the softstart.
the cap over the switch need to be Y type
(i think) but thats is only to avoid spark in the switch.
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We should not forget that primary current is 4.5(in my case) smaller than one in secondaryif the fuse holds, what else is there to worry about
are you not building heavy duty classA using only tough components
maybe it also saves on the switch with a film cap on its terminals
.AudioSan, that exactly what I was talking about:"at the same time that the transformer is restricted by the softstart". The softstart restrict the whole circuit in terms of energy, so you do not have enough energy to melt things down... I hope so
I have a working transformers as a proof of my words dazed2, yep, they are WIMA MKP4 4.7uf
We should not forget that primary current is 4.5(in my case) smaller than one in secondary
AudioSan, that exactly what I was talking about:"at the same time that the transformer is restricted by the softstart". The softstart restrict the whole circuit in terms of energy, so you do not have enough energy to melt things down... I hope so
dazed2, yep, they are WIMA MKP4 4.7uf
no. you only restrict the transformer. the demand from the cap bank will still be there, trying to extract the current from the transformer(low resistance). with a slow charge, the capbank will see a higher resistance and slowly charge.
Well it is kinda relavent to me too I'm using.... cough cough... 0.564F in the power supply so I'm a little concerned too.
I decided to get the soft start from Connexxelectronics here but swap out the thermistor for a 5ohm 50W heatsinked encased resistor. I'm hoping it will work....
Its a 1500VA trafo.
PKI : those bypass caps, are you using it to lower ESR and have faster transients?
I decided to get the soft start from Connexxelectronics here but swap out the thermistor for a 5ohm 50W heatsinked encased resistor. I'm hoping it will work....
Its a 1500VA trafo.
PKI : those bypass caps, are you using it to lower ESR and have faster transients?
I have posted many times that soft start and slow charge are very different strategies.
Soft start is to allow the transformer to start up with blowing the close rated fuse in the primary circuit. This is a short term requirement of about 100 to 300ms.
Slow charge is the current limiting AFTER the transformer has started.
Power Thermistors in the secondary circuit do this slow charge duty very well. This is a much longer term requirement usually longer than 5s.
Both types of current limiter, whetcher using resistor or thermistors increase the supply source impedance. Both types of limiter need to be shorted out to bring back the advantages of low source impedance.
And now the contentious part:
Don't try to achieve the dual duty of soft start and slow charge by inserting a long time duration current limiter in the primary circuit.
I have posted many times that soft start and slow charge are very different strategies.
Soft start is to allow the transformer to start up without blowing the close rated fuse in the primary circuit. This is a short term requirement of about 100 to 300ms.
Slow charge is the current limiting in the smoothing capacitor circuit AFTER the transformer has started.
Power Thermistors in the secondary circuit do this slow charge duty very well. This is a much longer term requirement, usually longer than 5s.
Both types of current limiter, whether using resistor or thermistors, increase the supply source impedance. Both types of limiter need to be shorted out to bring back the advantages of low source impedance.
And now the contentious part:
Don't try to achieve the dual duty of soft start and slow charge by inserting a long time duration current limiter in the primary circuit.
They won't let me edit out the errors in my earlier post so I have rewritten it here.
Soft start is to allow the transformer to start up without blowing the close rated fuse in the primary circuit. This is a short term requirement of about 100 to 300ms.
Slow charge is the current limiting in the smoothing capacitor circuit AFTER the transformer has started.
Power Thermistors in the secondary circuit do this slow charge duty very well. This is a much longer term requirement, usually longer than 5s.
Both types of current limiter, whether using resistor or thermistors, increase the supply source impedance. Both types of limiter need to be shorted out to bring back the advantages of low source impedance.
And now the contentious part:
Don't try to achieve the dual duty of soft start and slow charge by inserting a long time duration current limiter in the primary circuit.
They won't let me edit out the errors in my earlier post so I have rewritten it here.
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My english is not very tec.... please someone draw for me. maybe Zen????
this is interesting for me since I'm going for 4x47000 for 1 channel. What trafos size VA and Output Volt?
what rail volt is max when cascoded?
will be water cooled, so heat no problem, thinking no insulator between output and sink....
this is interesting for me since I'm going for 4x47000 for 1 channel. What trafos size VA and Output Volt?
what rail volt is max when cascoded?
will be water cooled, so heat no problem, thinking no insulator between output and sink....
