When used in a computer itgoes thru a series of test while computer is booting up. After the power supp;yu and computer are running the power supply will sense any unusaul loads which may be signs of shorts and shut down. Some chargers have fairly large surge currents during start up and some power supplies see these as shorts or the start up surges exceed the amps. capabilities of the power supply.
Rule of thumb which few follow is that a swither type power supply should always have a load attached befor it is powered up.
From first post of this thread
Recommended connecting way:
1. Connect iCharger's input power supply, and turn on it.
2. Connect Li batteries' balance port
3. Connect the main charging port's positive pole to cells' positive pole, and then connect negative pole to cells' negative pole (this will avoid striking fire while connecting Li cells).
4. Start charging and discharging...
5. After finishing charging and discharging, pls disconnect the cell and charger, and then turn off the charger's power supply.