Just a quicky that for once requires a simple yes or no answer!
I have an RS bench PSU that has 2 terminals that give a fixed 5v and 0v, and 3 terminals that provide a variable 0 to 15v+ a 0v and a 0 to 15v-.
I have used it for years and just come upon a circuit that would be easier to build if I could common both 0v connections on the breadboard, would this do any harm?
Just a quicky that for once requires a simple yes or no answer!
I have an RS bench PSU that has 2 terminals that give a fixed 5v and 0v, and 3 terminals that provide a variable 0 to 15v+ a 0v and a 0 to 15v-.
I have used it for years and just come upon a circuit that would be easier to build if I could common both 0v connections on the breadboard, would this do any harm?
If you really want to double check, bung a 100ma fuse between both 0v lines on the power supply and run it like that for a while - if the fuse blows then you know you probably can't.
Other thing to do would be to measure the continuity between both 0v posts and if its less than 1/2 ohm or so you should be fine.
Gut feeling would be you should be able to do it without any problems.
I would have assumed that the ground for the +5 was connected to the chassis (and earth ground if there's a grounded cord) and that the variable supply's common floated and that it was an option to connect the common to the chassis. Didn't the unit come with an instruction book and schematic? If not, can't you get one?
Turn the power supply ON, set the +- variable to say 10V, and use your voltmeter to measure the voltage between the two 0V terminals. Do this on both the AC and DC ranges of the meter. If you measure next to nothing, it it safe to connect them together.
Hi Al,
You said you wanted a 'Yes or No' answer... you didnt ask how to check it out.
In my experience where a bench top PSU has a separate 0V for the different voltage outputs,
they are usually isolated from each other.. [the 0V's that is]
And unless marked with a 'chassis' connection symbol, the 0V's are also ground free.
Its very easy to check this out using a DMM.
Dont forget to add a medium sized electrolytic, say 220uF and a 0.1uF at the connection point on your breadboard,
for each psu supply wire.
The type of smoke you want to avoid is the smoke with the 'dark brown smell'