BS9000 PSU circuit schematics.

6 replies

Hello beoworlders,

 I have a BS9000 which has a failed PSU. I've taken it to an electronics repairman who found a failed (smoking, actually) resistor along with a fuse which keeps blowing. He's taken off and tested a number of parts but can't find the failed component which is shorting out.

 

I supplied him with the BS9000 MK1 manual from the site, however it's missing section 2-10 which seems to have the PSU schematics(rather than just block diagram). Does anyone have a copy of section 2-10 of the BS9000 service manual? I'll ask for details of which circuit/fuse keeps blowing and update this thread.

 

Cheers

 

The schematic for the power supply and power switching is in fact on page 2-31,but I'm not very optimistic that your techie will be able to repair the module.

They are not really designed to be repaired,but we all try if we can?

These supplies are very sophisticated with many self protection devices built in that usually means the machine will shut down in case of faults.

If your's is burning,it suggests a major component fail,probably in the primary area of the supply.

It might be worth looking for a salvaged module?

Regards,

Nick

solderon29 wrote:

The schematic for the power supply and power switching is in fact on page 2-31,but I'm not very optimistic that your techie will be able to repair the module.

 

Daily job to fix these.

 

Location: Utrecht

Quite a challenge to achieve "Less is More" while having the Beovirus.

thunder wrote:

 

 who found a failed (smoking, actually) resistor along with a fuse which keeps blowing. He's taken off and tested a number of parts but can't find the failed component which is shorting out.

That's uncommon. The resistor doesn't cause the blowing fuse. The repairman probably only tried to replace the resistor and afterwards the fuse keeps blowing. But normally the fuses are never blown. Exept the one next to the transformer. Then you have a failing motorcontrolboard.

 

Location: Utrecht

Quite a challenge to achieve "Less is More" while having the Beovirus.

So the repairman has thrown in the towel on this project. He can't track down what is causing the PSU to fail.

The rest of the unit seems to work when you supply correct voltage - radio/cd plays until it resets. 

 

Is there anyone on beoworld forums that does B&O repairs? I can send the PSU to them to be repaired. 

 

Beobuddy .... as he mentions above.

Martin

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