hippy wrote: ↑
Thu Jan 18, 2018 12:43 pm
sparkyhall wrote: ↑
Thu Jan 18, 2018 12:13 pm
That's extremely unlikely because most power supplies can only source, not sink, current.
Any difference in voltages at the two ends of a conductor will cause current to flow in that conductor.
I don't think you understand the difference between source and sink.
In general, current can only flow out of a power supply. When you put a load on a power supply it provide just the right current to maintain its output voltage. If the voltage drops the PSU will provide more current (upto its current limit). If the load changes and the voltage rises the PSU provides less current to reduce the voltage. This is just appliaction of ohm's law.
But if some other power supply is providing too much voltage a PSU will not sink current in a attempt to reduce the voltage.
Last edited by PeterO
on Thu Jan 18, 2018 5:53 pm, edited 1 time in total.
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