my LM3886 Amply fire

jamal

Member
2010-09-20 1:53 pm
my LM3886 Amply fire

[IMGDEAD]https://i52.photobucket.com/albums/g30/james_rai/BBR0015670.jpg[/IMGDEAD]

[IMGDEAD]https://i52.photobucket.com/albums/g30/james_rai/BBR0015668.jpg[/IMGDEAD]

[IMGDEAD]https://i52.photobucket.com/albums/g30/james_rai/BBR0015669.jpg[/IMGDEAD]

[IMGDEAD]https://i52.photobucket.com/albums/g30/james_rai/BBR0015671.jpg[/IMGDEAD]
 

jamal

Member
2010-09-20 1:53 pm
hey, Thanks. I just added 5 LED tri color . each LED will turn from red to blue then green. then it will blink blink blink and whole process start again by itself without additional circuit. all is build in to LED.
some one thought the plastic box is on fire, until I told them it is not.

AndrewT, yup those connection are connected to earth. infact the connection have been change drastically to include star topology .the current photo is not taken yet.

Nice construction job and design. The amp should produce a delicious, fresh,clear, Sterelite Food Container crisp sound! A little unconventional in choice of cabinet, but conservatively designed, and should be reliable. Interesting!
 
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Hi,
the primary fuse can be rated as 3 * VA / supply voltage.
This results in a big fuse value that does not suffer nuisance blowing at start up but needs an enormous fault current to pass to make it rupture. I don't like this, there is a risk of severe overheating in the faulty apparatus before the fuse eventually blows.
I prefer to close rate the fuse (Fuse rating <= VA / supply voltage), but this requires the use of a soft start to prevent nuisance blowing at start up.

The secondary fuses (one in each supply rail after the smoothing caps) can be rated as 0.5 * sqrt[ Output Power / speaker Ohms]

Use F (fast) rated fuses in the secondaries and use T (time delayed) rated fuse in the primary.
 
but I dont like to use fuse

So Amply Fire will be more than just a name. It will be an omen.

A fuse is a safety device. Its purpose is to protect people from touching conductive parts that by some fault carry high voltage and it protects the following components from overheating and catching fire in case of overcurrent. Skipping the fuse is a bad idea.

you see I am using heavy gauge wires to accomplish low resistance for high current flow, then if I put a thinly fuse wire will it effect the current flow if not then wire people use heavy gauge to power large load......thanks

The current will flow either way. Such a fine wire fuse will produce a voltage drop of ~100 mV. That means your amplifier will clip 0,0025 W earlier with a 4 Ohm load or 0,00125 W earlier with an 8 Ohm load than without the fuse.