1 loop, two PCs

[Henderjc]

Hi all, I am currently running a dual PC system with two seperate loops. I am not overly happy with the result as things are cluttered and not as clean as I would like. It was tough to fit two seperate reservoirs and pumps along with two power supplies and all the wiring. It was also my first time using hard tubing and my bends were not great.

In order to clean this up I want to make it one large loop, but my dilemma is how to make the pump run when EITHER power supply is turned on. Any help would be much appreciated!

 

[unholythree]

Why not have a separate power supply just for the pump? Meanwell makes good switching power supplies, and a 50W 120v AC to 12V (or 24V) DC model would be $15 or less. You'd just need something like a power entry module for a second power cord.

 

[Tsumi]

Two diodes would be all you need. If you don't trust the power for the pump going through the diodes, then two diodes to a relay powered by a separate PSU.

In this scenario, the diodes would need to be rated for at least 12 volts and 3 amps (D5 pumps use ~2 amps). You would also probably want to look for diodes that have low voltage drops.

Alternatively:

In this scenario, the diodes can be as little as 0.5 amps, and the voltage drop across the diode doesn't really matter.