Lab Power Supply Current Limiting Q

[Wynand]

I'm currently designing a Lab Power Supply to use for various Audio Projects.

I'm using a PC Power supply for 5 12 -5 -12 Volts for a beginning but I want the +and- 0-35v Supply to be the heart of it.

I've decided to use the LM338 T0-3 as my positive voltage regulator.
It'll also be used for the current limiting (5A should be enough limiting?)

My problem is.... do I need a current limiting circuit on the negative supply line aswell or does all the current come from the positive side(what happens at GND in respect to -V)

 

[Wynand]

Heres a pic to show what I dont understand

 

[ctardi]

Don't quote me on this, but i think it will work with only + Limited.

 

[Nordic]

Wynand if you do manage to pull it off gimme a shout....
I'd be interested in the setup.... have a few PSU's I can pilage for parts...

 

[TwoSpoons]

You DO need your current limit in both + and - supply. It is quite possible to pull current from GND to V- without any current from V+.

Proof:
Connect light bulb from GND to V-. Does it glow? Of course it does!