mrs kymm's controller unit's

[scamper]

good job on the ground then Also not sure how you are planning on using one supply for injection only, essentially connecting that up to a string powered by the falcon will mean you then have 2 supplies in parallel.

Unless the psus are meanwells (or similar) which have load sharing and can do this.

If they are injected at separate points and not directly paralleled you shouldn't have a problem. Power is power and the load will draw what it wants from wherever it can get it easiest.
I have been using the cheap Chinese supplies for years and never had a problem.

 

[marmalade]

not sure what you mean by separate points, if they are segregated from each other, they will be fine.

If not, and joined together (ie one at each end of a string for example) the one with the lowest output impedance (by even a few milliohms) will be doing the lions share of the work. If you put an ammeter on both supplies it will be pretty obvious they won't match.

Then there's the potential of one psu faulting or crowbarring and loading up the other (can be negated with a diode, rated at the output capacity though).

Sorry to disagree, but it's simply not good practice to do this (unless they are designed specifically for current/load sharing), and many smps white papers will explain in greater detail why.

Using MEAN WELL Power Supplies in Parallel

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