The iPower does not have a connection to mains earth – how can it create a ground loop when plugged in directly to mains?
Answer: The iPower itself cannot create an earth loop. In fact, it is designed without mains earth explicitly to avoid the potential of creating earth loops!
However, as with any power supply, a small amount of leakage current will flow in the power supply unit output (ground/positive). It will be, by design, in the region of 10s of micro-ampere (in other words in compliance with medical equipment directives).