Parallel connection between distinct DC Bench Power Supplies

Question

I'm using a 30V DC power supply which is said to be 30V/3A with a switch between series/indep/parallel mode. Connecting the supplies in parallel, we have a maximum of 6A. However, in order to execute my current project, I´ll need over 10A. When we parallel connect the outputs, even if there is a small voltage difference, the internal control ends up managing to balance this difference so the output is the same in both channels.

My DC Supply is meant to be a linear ICEL PS-5001.0014 30V/3A.

Looking at the datasheet of an Agilent DC power supply, I read that I can actually connect two independent linear supplies in parallel. So, I could buy two distinct DC supplies and connect their channels such as I have them in parallel. I was wondering if I could also do it with my DC power supply.

I have this question because, even though I've purchased the supply as a genuine ICEL DC Power supply, I found many other ones from china (this means mine is just a copied version sold as genuine) which may be manufactured with low quality components. My question is, can I purchase another similar linear DC Power Supply, connect its channels in parallel and finally connect the two DC supplies in parallel again (in order to have 30V/12A)? Can I trust in the internal control so it will manage to balance all voltage differences (let's say one channel has V=29.99[V] and other has V=30.01[V])?

I'm attatching a picture of my DC power supply and two others I've found on internet that actually are the same as mine.

Answer 1

It is very likely that there will be no problem connecting them in parallel, as long as you can get the Voltages close to equal. A few mV will probably not matter. It is unlikely that current will flow into the output of the lower voltage supply unless it is the type of supply specifically designed to operate in this fashion (e.g, Hameg).

You could try asking the manufacturer about your question, although if it is "fake" then that might not matter. Also, you could consider renting a beefy supply just for this project.

Not all supplies can be put in series. It depends on whether they are isolated from Earth ground. Yours probably can be put in series, because it has green jacks (for "Earth" ground.)

Good luck to you.

Answer 2

Sorry if I´m late but maybe it can help other guys. Supposing the circuit will drain 10 amps at 30 volts. Connect the power supplies in parallel and set both of them to 30V and 6 amps. When you turn the circuit on, they will try to reach the 30 volts unless they are limited by the current of 6 amps (as the power supplies work). The one who reaches the current limit first will show a slightly lower voltage so that the second one will supply the excess current to complete 10 amps.