150W Soft Starter

I was trying to build a power supply from an arc psu, which I did but now what the problem is due to high starter current of 775 motor the protection feature of psu turns on and switches it off. The solution could be a soft starter but I can't find which specifies this motor only. Also I have a very little knowledge of electronics

What is the current rating of the supply.
A crude method would be to use something like a vehicle bulb inline with the motor to limit the current.

The PSU can handle upto 12A on 12V side, but the required current of the motor during work is only 2.5A(I measured if on a car battery)

to do the job corrfectly ypu need a current limit circuit.