I faced some problem with my LM317 power supply, when i need to check 48 volt circuit, i do connect two power supply in series to get 48volt or so. but if suddenly two terminals (48V) are short circuited the LM317 power supply is blow up and 120Ohm resistor (hooked output to Adj pin) also blow. I insert all protection diode as recommended but i don't able to protect LM317. My other PSU was fixed 30V 2.5A SMPS.
please suggest me what can i try to do others way to protect LM317.
please suggest me what can i try to do others way to protect LM317.