You find the datasheet here:
http://www.onsemi.com/pub/Collateral/MJ11012-D.PDF
55 C is nothing for a Power Amp, but normally you would try to avoid anything over 70 C as the temperature limits the safe maximum Current through the transistor..........
http://www.onsemi.com/pub/Collateral/MJ11012-D.PDF
55 C is nothing for a Power Amp, but normally you would try to avoid anything over 70 C as the temperature limits the safe maximum Current through the transistor..........
Hmmm...
The transistor case is getting hot , the heatsink is pretty hot too ..
I could put my hand on it .. i stick it and i didn't burn my finger ... i only got shocked by the 40 V that the amplfier power supply give ..
If i gonna add some fan's , how should i put them ?
I want to put ( one on each board ) them inside the case ( with hold outside ) to suck air from the case and throw it out ( i will place them over the output transistors )
And two on each heatsink to suck air from it .
How should i put them ? To suck air from the case ? Or the suck air from outside and throw it in the case ?
Thanks , Mihai .
The transistor case is getting hot , the heatsink is pretty hot too ..
I could put my hand on it .. i stick it and i didn't burn my finger ... i only got shocked by the 40 V that the amplfier power supply give ..
If i gonna add some fan's , how should i put them ?
I want to put ( one on each board ) them inside the case ( with hold outside ) to suck air from the case and throw it out ( i will place them over the output transistors )
And two on each heatsink to suck air from it .
How should i put them ? To suck air from the case ? Or the suck air from outside and throw it in the case ?
Thanks , Mihai .
Attachments
Directly above them, I would blow the air onto the devices..I think that will be a more focussed cooling stream..but, that will still be an ineffective use of the fans..
I would prefer the fans either over the fins, or under, blowing across them. that is better.
Cheers, John.
PS..gotta bolt..happy holidays, good luck.
I would prefer the fans either over the fins, or under, blowing across them. that is better.
Cheers, John.
PS..gotta bolt..happy holidays, good luck.
Re: Hmmm...
How did you measure the temp? If you can put your fingers on them withour burning (you really can KEEP them on it), they propably aren't a whole lot above 40 celcius.
Jan Didden
darkm4n said:The transistor case is getting hot , the heatsink is pretty hot too ..
I could put my hand on it .. i stick it and i didn't burn my finger ... i only got shocked by the 40 V that the amplfier power supply give ..
If i gonna add some fan's , how should i put them ?
I want to put ( one on each board ) them inside the case ( with hold outside ) to suck air from the case and throw it out ( i will place them over the output transistors )
And two on each heatsink to suck air from it .
How should i put them ? To suck air from the case ? Or the suck air from outside and throw it in the case ?
Thanks , Mihai .
How did you measure the temp? If you can put your fingers on them withour burning (you really can KEEP them on it), they propably aren't a whole lot above 40 celcius.
Jan Didden
Ok .
The kit have 400 W x 2 at 4 Ohm , it's a bridged amp ( with a TDA circuit , it can be seen on the board's , it's that long cip , black )
It sound very good .. the only problem is the temp.
At low volume it's about 40 C , at high volume i don't know .. but i think it's about 80 C ...
That's why i want some coolers ..
I still don't know how to put them ... maybe 2 on each board .. mounted on the headsink , not across the fins , on the fins . If i put 2 on each heatsink it should cover it ...
Thank's
The kit have 400 W x 2 at 4 Ohm , it's a bridged amp ( with a TDA circuit , it can be seen on the board's , it's that long cip , black )
It sound very good .. the only problem is the temp.
At low volume it's about 40 C , at high volume i don't know .. but i think it's about 80 C ...
That's why i want some coolers ..
I still don't know how to put them ... maybe 2 on each board .. mounted on the headsink , not across the fins , on the fins . If i put 2 on each heatsink it should cover it ...
Thank's
Re: Ok .
What rail voltages do you have?
Where are the kits from, respectively could you post any schematics of the kit?
darkm4n said:The kit have 400 W x 2 at 4 Ohm , it's a bridged amp ( with a TDA circuit , it can be seen on the board's , it's that long cip , black )
What rail voltages do you have?
Where are the kits from, respectively could you post any schematics of the kit?
Hmm..
I use 42 V rail's , i don't have a schematic of the kit's .. sorry ..
Whan i first saw those kit's i couldn't belive their power at a low voltage .. ( 42 V )
But .. i realised that it's true .. because it's a bridged amp .. i ask a friend to mesure with an osciloscope the max power and result about 408 W at 4 Ohm .
Thank's .
I use 42 V rail's , i don't have a schematic of the kit's .. sorry ..
Whan i first saw those kit's i couldn't belive their power at a low voltage .. ( 42 V )
But .. i realised that it's true .. because it's a bridged amp .. i ask a friend to mesure with an osciloscope the max power and result about 408 W at 4 Ohm .
Thank's .
Re: Hmm..
Do you have a list of used parts?
darkm4n said:I use 42 V rail's , i don't have a schematic of the kit's .. sorry ..
Do you have a list of used parts?
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