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Old 26th November 2007, 11:53 PM   #1
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Default When to use softstart

Hey all.

I'm planning on building an F3 power amp, and am considering going dual mono (why not !!!).

Anyways, I know that when your transformer requirements are beyond 300VA, a softstart is recommended, but is that per transformer, or overall ?

I'm considering 2 250VA transformers (with 66000uF after each of them). In this scenario, since the inrush current is split over two transformers, I'm not sure if the softstart is required.
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Old 26th November 2007, 11:57 PM   #2
Zen Mod is offline Zen Mod  Serbia
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Default Re: When to use softstart

Quote:
Originally posted by lordvader
Hey all.

I'm planning on building an F3 power amp, and am considering going dual mono (why not !!!).

Anyways, I know that when your transformer requirements are beyond 300VA, a softstart is recommended, but is that per transformer, or overall ?

I'm considering 2 250VA transformers (with 66000uF after each of them). In this scenario, since the inrush current is split over two transformers, I'm not sure if the softstart is required.

it's not just VA rating of xformer , but also No. of kilouF you have after ;

in any case - use CL60 as Papa does and enjoy
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Old 27th November 2007, 12:23 AM   #3
Magura is offline Magura  Denmark
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Default Re: Re: When to use softstart

Quote:
Originally posted by Zen Mod



it's not just VA rating of xformer , but also No. of kilouF you have after ;


True, but the limit is somewhat more than 500VA and 66.000uF.

I start up my 1000VA and 200.000uF PSU's without softstart, with no problems.


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Old 27th November 2007, 12:40 AM   #4
Zen Mod is offline Zen Mod  Serbia
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Default Re: Re: Re: When to use softstart

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Originally posted by Magura



True, but the limit is somewhat more than 500VA and 66.000uF.

I start up my 1000VA and 200.000uF PSU's without softstart, with no problems.


Magura

from which line ?

what circuit brakers/fuses you have on that line .......... ?

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Old 27th November 2007, 01:25 AM   #5
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Default Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Zen Mod



from which line ?

what circuit brakers/fuses you have on that line .......... ?

230V 13A


Magura
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Old 27th November 2007, 01:33 AM   #6
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Default Re: Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Magura


230V 13A


Magura

fast ( automatic) ones or slow ( ceramic, melting) ones?
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Old 27th November 2007, 01:43 AM   #7
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Default Re: Re: Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Zen Mod



fast ( automatic) ones or slow ( ceramic, melting) ones?

Slow blow 13A ceramic fuses.


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Old 27th November 2007, 01:45 AM   #8
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Default Re: Re: Re: Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Magura



Slow blow 13A ceramic fuses.


Magura

and what's fuse in front of that sissy donut?
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Old 27th November 2007, 01:47 AM   #9
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Default Re: Re: Re: Re: Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Zen Mod



and what's fuse in front of that sissy donut?

10A slow blow.


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Old 27th November 2007, 01:49 AM   #10
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Default Re: Re: Re: Re: Re: Re: Re: Re: Re: When to use softstart

Quote:
Originally posted by Magura



10A slow blow.


Magura




that's why you don't need soft start .......

you can also put there smith nail instead

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