Proper care for a bench power supply

[rrick]

I have two variable DC power supplies, a switching 25 V and a linear 60/5/60 V. The manuals of either model don't really state what I should not do with them. An example regarding back feed: I was able to pump a 6mF capacitor up to 120V then dial down the voltage while still connected, so something internal absorbed the stored energy. What happens when I connect the power supply to a battery? Another concern is short circuiting. Are they fully protected across the entire range of dV/dt?

[jadew]

Hi Rick,

Welcome to the forum.

It depends a lot on the power supply but they should be fully protected against short circuits.

The reverse current issue could be handled in several ways:
1) If the power supply is designed to also sink current, it will sink it and bring the level down to the set level.
2) If it has a simple reverse current diode, it will bypass the output stage and end up back in the power rail that feeds the power supply - not a very good thing.
3) Could simply be blocked and the current draw that you noticed might be simply due to an internal dummy load.

Generally speaking they should support all kind of abuse, but as I said above, it's highly dependent on the power supply.