PM980S died out when switched on.Fuse was u/s.replaced ...and see details below

SOURCE: blown fuse and replaced it and burned the amp

BIG problem! You should NOT have replaced the fuse as additional damage has been done. I repaired a PMP5000 and I can tell you likely what you will find: The smoke and smell came from two power resistors that are part of the soft start circuit that now are toast. You will likely find several components in the main portion of the power supply that are toast. These will include transistors, resistors, diodes, and probably the small 8 pin switching regulator chip. There is a small power supply that comes on first which enables a relay that shorts out those soft start resistors AFTER the power amplifier BALANCES and normalizes.
The unit I repaired had severe damage due to arc-over at one power amp section. Three power transistors were destroyed there and board traces and charring had to be handled in that section.
The repaired unit had to be brought up with a light bulb in series with the line power cord to prevent further damage until all bad parts were discovered and repaired. You will need to take the unit to a shop that is expperienced with the product. The repair cost MAY be pretty high.

SOURCE: Behringer PMH 880S

Oh yes... I have repaired several of these supplies.
For the IGBT's use APT28GA60BD15 which are pricey at $9.28 from Digikey.com (still lower than alternative sources. Getting the heatsinks off, one of which has a thermal sensor as well is a real pain! Transformers don't fail...
The C2655's are really 2SC2655-Y and those I get from Allied. The mating 2SA1020-Y I believe is available either at Digikey.com or Mouser.com.
You will LIKELY find the IR2153 chip is blown and that I had to get from Allied. Usually one of the PL4148 surface mount gate drive speed up diodes is blown either short or open (D24 and D25).
Often transistor T9 is gonzo (BC856MTTCT).
Often the 10 or 22 ohm wirewound charging resistors are blown open. I use TWW10J20RE as replacemens for those. Be sure and use silicone to help support them.
Now when you are done with that, you need to find WHY the supply failed. It is either because a ceramic cap across the 85 volts failed OR one of the power amps arced out. If the unit has the HCA2400 amp in it I will tell you what happens: In the vicinity of the SPF9640 MOSFET and a big surface mounted cap will be an arc between layers of the multi-layer circuit board. This shorts and fries the IRFP250 MOSFET and BOTH SFP9640 MOSFETS. The repair of this is major involving carving out the "cancer" and reinsulating with epoxy and replacing blown carved out traces with hookup wire. The proceedure I can't document here, but failure to correct this will result in power supply failing again.
FOR YOUR SAFETY ONLY work on the supply using an isolation transformer. Use a 150 Watt lamp in series for testing to act as a fuse so you don't pop the supply again. DISCHARGE the 85 volt outputs BEFORE plugging the amps back on the power supply.

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SOURCE: I have a burnt resistor

Usually the amplifier will have "symmetry" and there will be matching resistors near the other power tubes that you can get the value from. This is PROBABLY a screen resistor for the tube and values are often around 470 ohms or so but I could not find a schematic. These USUALLY don't fail unless a tube has shorted. Heat sinks are NOT used. The best resistors for the purpose are "wire wound" ones and of a suitable wattage rating. Sometimes we put ceramic beads on the leads to raise the resistors off the board to allow air circulation. Occasionally solder will break and the arcing at the leads adds to the heat. If you trace where the resistor goes by pin number of the tube and the type of the tube that would help me to help you... trace a matching tube to the same pin and you will likely find a matching resistor. Note that some power resistors DO change color a bit after they get hot in use, but if they char or the coating falls off that is a failure.

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