“Brute Force” Parallel of Power Supplies

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You will notice in lots of of our instruction manuals a warning about not connecting power provides in parallel that wouldn't have present share capabilities.

At first it will appear a pleasant straightforward method to get further present.  Take two like power provides, join them collectively and they're going to ship twice the present?
Sadly there's a good likelihood that the 2 power provides won't present share on account of their output voltage set factors.  The power provide with the very best output voltage setting will ship as a lot present as it may well till it reaches its present restrict threshold after which the output voltage begins to drop.  The second power provide will then take over and supply the steadiness.  The output voltage may glitch through the transition, affecting system operation.

For instance, take two 24V 10A power provides with an over present set level of 120% powering a 15A load:

Power provide A may ship 12A (now at its present restrict level)

Power provide B would then ship 3A.

One may argue that the power provide is being protected by the present restrict.  There are two points with this although:

1.  A power provide will not be designed to function in present restrict indefinitely. Inside temperatures will rise, lowering the life of the product

2.   The security certifications for UL, CSA are primarily based on 100% load, not 120%

My advice is to make use of a power provide with the next present ranking, or select one with a present share feature.