Do I need a "power line filter" for my instruments power supply?

[peaman]

In my main battery box, there is a "Mar-P35 Powerline Filter" which fed the instruments which were in place until recently. The filter was not properly mounted, and instead was just placed between the two batteries, so seems likely it was not original equipment. I have removed all previous instruments and installed all new including B&G chart plotter, radar, wind and depth/speed sensors, and Raymarine wheel pilot, all connected with an NMEA 2000 network. I will soon clean up my battery box to make all proper, and I wonder if I can simply remove the power line filter, or am I likely going to need to replace it with an equivalent component to avoid any issues with the 12V supply to the instruments?

 

[Jerry VB]

I would be very surprised if your new instrumentation was bothered by alternator "whine." Electronics nowadays is much better than in the days when that filter was installed. Most electronics nowadays takes the raw 12v input and runs it through a switching power supply to generate the voltages needed by the instrumentation electronics. The alternator whine should be totally filtered out by the instrument's power supply.

I would remove it and watch for any ill effects on your instrumentation when motoring (alternator whine present) vs. sailing (no whine).