I just got this amp today with two blown IRFZ44N's in it replaced all 12 just to get smoke in the restistior next to the yellow box thing..not sure what that is. Took the yellow thing out amp functioned fine on my subs for ~30 min at full power with no problems. My question is Why was the resistor smoking and how bad is it to run the amp without that yellow thing in it? Sorry for the bad pics camera isnt that great.
PS yellow thing appears to be stamped either 7470nK 63 or T470nK 63
http://i227.photobucket.com/albums/dd146/mxracer592/AMP/DCP_3436.jpg
http://i227.photobucket.com/albums/dd146/mxracer592/AMP/DCP_3433.jpg
PS yellow thing appears to be stamped either 7470nK 63 or T470nK 63
http://i227.photobucket.com/albums/dd146/mxracer592/AMP/DCP_3436.jpg
http://i227.photobucket.com/albums/dd146/mxracer592/AMP/DCP_3433.jpg
The capacitor is a 470 nanoFarad 63 volt film capacitor with a ±10% tolerance. The 'T' is probably the manufacturer.
It appears that the capacitor is the wrong value. In all similar amps, the capacitor is a 47nF capacitor. A 470nF capacitor would allow much more of the square wave on the primary windings to pass through the resistor (instead of only passing the higher frequency ringing waveforms). This could cause the resistor to overheat. If you look at the other 3 snubber capacitors, you'll see that they're marked 473k 63.
It appears that the capacitor is the wrong value. In all similar amps, the capacitor is a 47nF capacitor. A 470nF capacitor would allow much more of the square wave on the primary windings to pass through the resistor (instead of only passing the higher frequency ringing waveforms). This could cause the resistor to overheat. If you look at the other 3 snubber capacitors, you'll see that they're marked 473k 63.
Virtually any film capacitor of the same value will work in that application.
47nF = 0.047uF
This should work well. Confirm that they're the correct size (physically) before ordering.
http://www.mouser.com/search/refine.aspx?Ntt=505-MKM20.047/100/5
47nF = 0.047uF
This should work well. Confirm that they're the correct size (physically) before ordering.
http://www.mouser.com/search/refine.aspx?Ntt=505-MKM20.047/100/5
http://www.radioshack.com/product/i...Metal+Film+Capacitors&fbc=1&parentPage=family
Perry, Would these work for the application or no?
Perry, Would these work for the application or no?
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