Hello Arikarbel. I have bench tested at 350VDC (albeit with a slightly different PCB for the LX200V20) and it worked fine. I have yet to test in the water but don’t anticipate significant issues. Depending what your input filter at your step-down regulator looks like, it may be necessary to alter your input impedance. I used a 68uH/10A inductor (in parallel with a 47Ohm resistor) in series between my data connection and the input of the 500W power supply. It worked fine on the bench, but was only a test with 30m of tether. Power wires were untwisted 22AWG, voltage was just over 350. however, I use a tether with 2 twisted pairs + power, so I haven’t really needed to run this option. I am now experimenting with running the FathomX (with added zero-cross circuity) over 240VAC. I’ll post once we have some good field data. Please let us all know how your setup goes.