8A with coolers added will probably be just fine.
What is the transient one shot peak current capability of your 8A rectifiers?
What is the continuous current you intend to draw through the 8A rectifiers?
Work out the Pq and size the cooler appropriately.
Inrush current is the current that flows in the primary circuit while the mains is trying to start up the transformer. This start up current does not flow in the secondary.
As the transformer starts to turn on it will start generating a secondary voltage. This secondary voltage charges up the capacitors. This is the current that flows through the 8A rectifiers.
If the start up current (primary) is of concern then use a soft start circuit, in series with the mains/primary.
If the charging current (secondary) is of concern then use a slow charge circuit, in series with the rectifiers.
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Andrew,
Can't one just put snubbers on a regular bridge rectfier to get the same result as a fast recovery diode? May be easier than separate diodes. If so, what would the value be for the caps?
Can't one just put snubbers on a regular bridge rectfier to get the same result as a fast recovery diode? May be easier than separate diodes. If so, what would the value be for the caps?
There is a paragraph by Nelson Pass somewhere, I think in one of the articles, where he says that fast recovery diodes are not all that beneficial for a PSU like this.
Well Well Well
It is al relevant now in'it
How do you calculate was it not somevere about post 263 all talked about.
Funny how people forghet so quikley
I did the calcs...
would have been posted in post 358 or 359.
""""But now is just so relevant.so realy best you going to get is go and read the paper because I am just posting for the sake of it and it make me fell so macho to make you believe that I did make the calculations and also rain can be wet when it falls downward...""""
Uhm may heven make 23 posts today good for my stats.
Apart from the abowe
Tanks to Zen Mod for first posting this.
It is al relevant now in'it
How do you calculate was it not somevere about post 263 all talked about.
Funny how people forghet so quikley
I did the calcs...
would have been posted in post 358 or 359.
""""But now is just so relevant.so realy best you going to get is go and read the paper because I am just posting for the sake of it and it make me fell so macho to make you believe that I did make the calculations and also rain can be wet when it falls downward...""""
Uhm may heven make 23 posts today good for my stats.
Apart from the abowe
Tanks to Zen Mod for first posting this.
Hi Andrew,
These have 40+ peak current.
Bias per device = 1.3A x 4 devices = 5.2A continuous draw.
I was just wondering because the recommended power supply specifies 30A bridges.
this does not sound right.
Are you referring to one mono amplifier or to a two channel stereo amplifier?
Do you know what output bias means and how to measure it?
I was referring to the standard F5. Two mosfets per channel, four for stereo. Each mosfet biased at 1.3A according to the measured voltage across the source resistor.
From your comment I'm guessing that this is different than output bias. Could you please elucidate?
6L6, Jim..... Just a heads up. I've posted some more pics of my F5 build under my "Beautiful music.....different drummer" thread. All I need now is a front panel, as in Front Panel Express.....!
Ken
Ken
Hi Ken
where did you buy the heatsinks ( black anodized)?
what is the size /price?
kannan
My heatsinks were the Conrad (Australian) ones, that were attained via a Group Buy. I believe I paid about $120 for them. You can probably Search the forums (use "F5" and "Conrad" as search terms), to see if some are still avilable from that buy.
Ken
I think Conrad heatsinks use a textured powder coat finish. The 10.08" profile from heatsink usa should work well too. You'll just have to get them painted or anodized on your own.
Where do you get them anodized in the US ? I am in Austin -Texas any place nearby ?
thanks
kannan
I imagine there's places that do anodizing in most metropolitan areas. They usually have minimums. Maybe better if you know someone that works in a machine shop or metal finishing and can have it done for you.
I suspect you'll have no trouble finding a shop that can handle this for you, either in Austin for San Antonio. Try the Yellow Pages (on-line or paper), looking for Metal Finishing, or Anodizing. If that doesn't work, look for a good local maching shop that does industrial fabrication, and they should be able to point you in the right direction.
PS: do not make the mistake I made.
Failed to give the anodizer a place where to atach an electrical conection.
They clamped the sink top and botom just the bit in the face I wanted to see
So maybe if you planing on mounting them a certain way is beter to be prepared or ask.
Price for anodising 2 heat sinks £40
Price for 10 £ 40
As long as not to big a number to fit in the bath price does not change (this aplies in UK ut cant see why there should be any difference down your side)
Failed to give the anodizer a place where to atach an electrical conection.
They clamped the sink top and botom just the bit in the face I wanted to see
So maybe if you planing on mounting them a certain way is beter to be prepared or ask.
Price for anodising 2 heat sinks £40
Price for 10 £ 40
As long as not to big a number to fit in the bath price does not change (this aplies in UK ut cant see why there should be any difference down your side)