Siemens SITOP Power Supply Component Level Repairs

Ever been curious as to how our repair process works for particular models? This article details the step-by-step process of repairing the components of a Siemens SITOP power supply, equipment that our certified technicians repair on a daily basis. Be sure to check out our YouTube video to see the process in action.

• This power supply is a 3-phase, 24V model that currently has no output.
• Our technician troubleshoots the three main sections of the supply down to the component level using a Huntron Tracker 2000.
• The caps have already been changed out as they are a common failure component.
• Next, the technician checks the input section by testing:
  • MOVs
  • Bus caps
  • Choke fuses
  • Diodes
  • Bridge
• Then he tests the intermediate section’s:
  • PWMs
  • Small caps
  • Transformers
  • Diodes
• Lastly, he checks the output section by testing:Output caps
  • Mosfets
• Typically, the intermediate section of the power supply is what affects the supply’s output capabilities, so the technician checks that section more closely.
• First, he checks the dual diodes for shorts. If the diodes are shorted, more damage to the supply will occur when he tests it by applying power.
• A bad diode has been found and needs to be replaced, so the technician removes the bad diode and solders in a new one.
• Next, he uses a load bank to fully load the supply down to 120% to ensure it’s ready to go back in service.
• At a 24V current, the meter stays at 24V and there is no sag in output amperage which means the unit has been properly repaired.

Be sure to leave us any questions or concerns you may have in the comments section below, and head over to gesrepair.com if you’re ready to get the quote process started on repairs of your Siemens SITOP power supply!