Can I reiterate, the service manual for the Dialog+ does
not have a circuit diagram for the power supply unit in it.
There is a block diagram which only shows the connections to the psu and a fuse list (which is also on the casing of the psu) and thats about it.
As for repairing the psu, this would prove extremely difficult off the machine as you have to have all the protective casings removed to access the psu to fault find and yet still have the psu connected to the machine to be able to receive control signals from the supervisor pcb to allow it to work properly.
With the machine in this condition it would be seriously hazardous to your health - with mains voltages every where, combined with you not having a schematic diagram and pcb layout, it would not be too safe to work on to say the least!
Also, as you are probably aware, the psu has very short cables connecting it to the Dialog so you would also need to ensure that it could not short on the rear door.
I can only suggest that you contact BBraun directly and ask if they can be of any assistance, they are very helpful.
I have included the link to their website.
BBraun Dialog+ Good luck!!