I've an old and cheap Atten TRP3005T Take a look at atten site
I have seen more expensive device that had a specific button that always disable the current emission every time you power off the device.
This is a security feature to avoid disastrous error when you attach a device to the power supply when the power supply is off and has been left to wrong settings (happen to me.. but without consequences... 15 volts on an Arduino when I want to use only 9 volts to test it)
Is there a way to add the same feature to my power supply ?
I think that I need to build a circuit with a dual mosfet but I'm not enough skilled to design it by myself... Also I'm not sure if this option draws power from the power supplier and can make some strange side-effects to power output like wrong value for voltage.