Thought the F5 current limiter was there to prevent the FETs from selfdestruction in case of shorts and other fault conditions. A fuse in the power rails would do the same thing, cut of the power once you reach a certain current level.
As this reliable amp accepts 2 ohms loads without burping and as i am wise enough not to short the outputs, i do not need current limiters.
If by chance i make a short, i am able to fix.
Those who intend to sell or give away their F5 have better to implement current limiting. One never knows what inexperimented users can do.
Edit : I fear fuses aren't fast enough
The F5 has the nice peculiarity not to show dc output when one rail is missing.
If by chance i make a short, i am able to fix.
Those who intend to sell or give away their F5 have better to implement current limiting. One never knows what inexperimented users can do.
Edit : I fear fuses aren't fast enough
The F5 has the nice peculiarity not to show dc output when one rail is missing.
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Never employing speaker protection before I dont feel like I can keep up the conversation but seems to me that rail fuses are not the way to go. You need two and if both dont blow at same time it seems potentially dangerous. A current limiter wont stop DC.
EDIT I see your post Bobo. Well that is a nice feature
EDIT I see your post Bobo. Well that is a nice feature
Now thats a nice feature, if only a fuse was fast enough, then you would have your current limiter right there. Would make the board layout simpler.
IMO Current limiter to start with and then improve the sound quality by taking it off but IMO only if super duper protection is in place.
How much power dissipation needed for a mosfet to run EGG 4 A at 28V ???
agree enough heath to get rid off but maybe it could just sit on one corner all by itself.
Well maybe with the negative rail one just to keep it company
Neutrality yes it may be but then you have loads of energy stored in the caps
Is the may be that scare me.
Channel or washer yey by me Single srew on tab no so much
Big 5mm copper bar on top even beter but then I tend to complicate things.
If it works for one it works for them all
How much power dissipation needed for a mosfet to run EGG 4 A at 28V ???
agree enough heath to get rid off but maybe it could just sit on one corner all by itself.
Well maybe with the negative rail one just to keep it company
Neutrality yes it may be but then you have loads of energy stored in the caps
Is the may be that scare me.
Channel or washer yey by me Single srew on tab no so much
Big 5mm copper bar on top even beter but then I tend to complicate things.
If it works for one it works for them all
Fuse should be after the caps, fuse blows, connection gone, caps no longer connected to amp. Their energy storage doesnt matter in that case.
No idea, my fuse knowledge is nil.
But depends on type of fuse, fast or slow blow fuse and some other things
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Thanks for this!
So I'm sold on the HS USA sinks but I'm trying to figure out what length I need for each side of the stereo amps.
Do you guys think 8" is enough or do I need to go all the way to 12" like Labjr did?
Thoughts?
an IRF540 could easily cope with 10A @ 100mVds and also cope with turning that OFF to become 0A @ 30Vds.
It might not even need a heatsink.
It might need a separate higher voltage for the gate control.
Well, Nelson recommends 96 sq in. per channel so I added a little more to be sure since I don't know how this particular heatsink will perform. I imagine a 10 in piece would be sufficient. I believe somewhere back in this thread someone tried a 7 inch piece of the same stuff and thought it ran a little hot.
http://www.cooperbussmann.com/pdf/28d25196-9efd-4d0b-ac91-c8e536281e0a.pdf
Specs for fuses
It take times fo them to blow depending on the current
Supose 20 V rails and a mosfet Blow
You need the fault loop impedence to find out the fault current.
0.47 R the resistor on the source + wiring iside the amp + resistance of the power cord +resistance of the wiring inside the house+ resistance of the wires from your fuse board to the earting point of the distribution system.
say total impedence of the circuit 1 ohm 20V / 1 =20 A
You put the termistor on the ground to reduce ground loops ad the resistance to that and recalculate
Pick your fuse and folow the curve to where those 20 A cross the time.
I think you seen the wires on the coil winding on the speaker.
If you shure it will take it fine
If you don't know and don't care fine again.
On the third hand if you don't know and prefer to be safe ask.
Thats what I did and for shure a mosfet is faster than a fuse.
Will they take it fo that long
Specs for fuses
It take times fo them to blow depending on the current
Supose 20 V rails and a mosfet Blow
You need the fault loop impedence to find out the fault current.
0.47 R the resistor on the source + wiring iside the amp + resistance of the power cord +resistance of the wiring inside the house+ resistance of the wires from your fuse board to the earting point of the distribution system.
say total impedence of the circuit 1 ohm 20V / 1 =20 A
You put the termistor on the ground to reduce ground loops ad the resistance to that and recalculate
Pick your fuse and folow the curve to where those 20 A cross the time.
I think you seen the wires on the coil winding on the speaker.
If you shure it will take it fine
If you don't know and don't care fine again.
On the third hand if you don't know and prefer to be safe ask.
Thats what I did and for shure a mosfet is faster than a fuse.
Will they take it fo that long
http://www.diyaudio.com/forums/atta...1290688364-balanced-f5-question-sinks-001.jpg
My sinks black anodised now
300X400x83
But I got 4 ohms speakers and may build B2 or aleph once I have finished the F5 balanced
My sinks black anodised now
300X400x83
But I got 4 ohms speakers and may build B2 or aleph once I have finished the F5 balanced
My heatsinks in cm are 150*350 and the fins are 50mm. With 1.4 amp on each mosfet it get warm, but not hot. I use raw aluminum.
D.
typo?
150cm*350cm would need a crane to install them.
What size are the fins? 350*50 or 150*50?
Are they aligned vertically for best air flow?
How thick is the backplate?
How have you attached the FETs to the heatsink?
I can see they never get hot !
150cm*350cm would need a crane to install them.
What size are the fins? 350*50 or 150*50?
Are they aligned vertically for best air flow?
How thick is the backplate?
How have you attached the FETs to the heatsink?
Look for the exact brand and model of the fuse and see it in their datasheet.