hifonics 1200

[timwebb]

im working on this amp and i got it to play but the output driver card get really hot then the relay clicks.but the amp doesnt turn off or go into protect.any idea what that could be?

 

[timwebb]

i think i found the issue. i get a bad signal on half of the output transistors.

 

[Perry Babin]

You need to give the exact model number. Even then, more information may be needed because at least one model number hifonics amp had 2 different boards.

 

[timwebb]

its the bxi1208

 

[Perry Babin]

The driver boards run hot, especially the two 1D transistors in the center of the board (you should replace them, even if they're not defective).

Measure the voltage across the relay coil. Does the voltage drop when the relay drops out?

 

[timwebb]

the driver card get hot at idle with no load on it. there was a cold joint at the relay that was arcing. im going to measure it now..

 

[Perry Babin]

The components in a class D amp (except for the output transistors) operate at approximately the same temperature whether it's idling or driving its lowest rated load at full power.