I'm no expert when it comes to caps and transformers either, but limiting current generally means you're cutting voltage too, because V=RxI. What I do know is that the voltage across a capacitor increases slowly when it's charged through a limiting resistor, but I don't know about transformers.
That's the whole point of the relay 
It switches between charging through the softstart resistor and going straight to AC, like in any other softstart circuit. The only difference is that this relay has a 220V AC coil connected directly after the resistor, so it'll switch over as soon as the amp gets close to working voltage.
I haven't checked if this actually works, I just think it should
It switches between charging through the softstart resistor and going straight to AC, like in any other softstart circuit. The only difference is that this relay has a 220V AC coil connected directly after the resistor, so it'll switch over as soon as the amp gets close to working voltage.I haven't checked if this actually works, I just think it should
The "best" way would probably be using some timer electronics and/or a current sensor, but that's just so much work... I already have an LC Audio softstart, but I think it might be too wimpy for 2x 1300 VA and 180000 uF. Any comments on that? If it is too small, I'll try my direct relay.
Soft start question
You guys are on the right track with a resistor in the line bypassed with a good relay. The first thing to do is to find one of the power supply inrush limiters that is suitable to substitute for a fixed value resistor. They should be available from any of the larger suppliers.
To trip the relay just use the rail voltage dropped with a suitable resistor. Putting an electrolytic across the relay coil allows adjustment of the delay to what ever you think is best.
Great looking amps! I do appreciate how much work all the metal cutting took.
Roger
You guys are on the right track with a resistor in the line bypassed with a good relay. The first thing to do is to find one of the power supply inrush limiters that is suitable to substitute for a fixed value resistor. They should be available from any of the larger suppliers.
To trip the relay just use the rail voltage dropped with a suitable resistor. Putting an electrolytic across the relay coil allows adjustment of the delay to what ever you think is best.
Great looking amps! I do appreciate how much work all the metal cutting took.
Roger
Re: Soft start question
yep, thats what im kinda thinking. i want to keep it as simple as possible. i would love to offer a group buy for it that wouldnt cost a lot. it just sucks that you can buy a hypex module for about twice what a softstart costs. it doesnt make a whole lot of sense.
ill be starting a thread some day for a cheap softstart. maybe we can develop something flexible and cheap. something that could even be hand-wired on a PCB board too.
thanks for the compliments on the amp. they are breaking in now and are sounding SO much better. im very impressed.
sx881663 said:
yep, thats what im kinda thinking. i want to keep it as simple as possible. i would love to offer a group buy for it that wouldnt cost a lot. it just sucks that you can buy a hypex module for about twice what a softstart costs. it doesnt make a whole lot of sense.
ill be starting a thread some day for a cheap softstart. maybe we can develop something flexible and cheap. something that could even be hand-wired on a PCB board too.
thanks for the compliments on the amp. they are breaking in now and are sounding SO much better. im very impressed.
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