need help in repair\testing of this smps

[stoica adrian]

I have this telekom smps. When i power it up, the line fuse blows. I use an autotransformer for a slow power it ( is the same problem without autotransformer). When my voltage is at around 110V, i can see how the internal relay from the smps are closing, and then a large current is absorbing frome the line blowing the fuse of the line smps  ( 4-6A at the autotransformer ampermeter) . The question is .. what can i use to limit the current, there is something special fore a start up of this kind of telecom power supply?, because i appear that this kind of smps are used along a controller, and ja, i dont have that controller.I dont have a lot of experience in repair this kind of smps. i am electronics technician at my background. Thank you all for the support

Obs- i measure all the components, i don't find a problem with them

[tautech]

I'm no expert with SMPS but there are few basic steps that can help with trouble shooting.

No particular order:
1. Identify controller and find datasheets, often "typical application" examples are closely copied by manufacturers in their designs.
2. Power on with a Dim Bulb tester in series with the mains supply, it will limit inrush current are preserve fuses. Google it.  You set the supply current value by selection of the bulb wattage.
3. Power only the controller from a bench PSU and check for the correct waveforms without risk from mains voltages.

Simple failures you should check for:
Resistor/s, or chain of, that supply current to the controller from rectified mains for startup.
Local bulk cap to the controller, ~20-50 uF, gone high ESR or drifted in value.
Flyback diode that supplies controller operating current for continious operation.
UVLO values