M12 connectors for mast light and wind transducer wiring?


Member II
TL-DR - is anyone using M12 connectors for mast light connections?

I'm running new wire for my E25 mast lighting and installing an ST60 wind transducer. I have old wiring for, but no current, mast VHF antenna (and don't plan to add a new antenna for now-I use a handheld for my lake). The existing wire runs up through the compression post and into the cast mast step. The light wire exists the port side of the mast step and is connected to an old GX16/CB mic style plug (not waterproof) likely from the 1980s. That plug goes into a GX16 socket in the side of the mast. The VHF wire (which I plan to remove remove for the wind transducer wire) exists out the starboard side of the mast step to a 90 degree plug, and that plugs into a VHF receptacle in the mast. I have attached a few pics of the more or less current situation (I had to add a CB mic extension cord on the lights to get through the season as I had to shorten and re-solder the wires to remove some corrosion, which made the wire too short to connect at the mast connection). The light wiring is substandard and butt connected to the factory wiring inside the mast step. The metal mic extension plug is already showing some rust from 1 season.

I am inclined to work to keep the wire routing/connection points rather than using a more typical through deck cable gland or cable outlet through the cabin top, as my current situation doesn't leak and has existing holes. I need to be able to disconnect the wiring at the mast, as I have a deck stepped mast that is raised and lowered each season. I can't easily run the wires to the boat and use a terminal block inside the boat, as there is not easy access to the compression post area and I don't have a headliner like bigger boats to hide such a connector/terminal block. I either need connectors on the mast step and side of mast, or a wire exiting the mast and attaching to a new connector mounted to the cabin top.

Existing mast light connections

Mast base GX16 wire.jpg

GX16 connector.jpg

GX16 socket.jpg

Mast GX16 connector.jpg

Existing VHF (cover cap already removed)

VHF mast base wiring.jpg

VHF mast connector.jpg

I have struggled to find waterproof connectors and panel mount receptacles that would work to replace the existing setup. I thought I might need to go with a mil spec Amphanol 97-3102 receptacle and 3106 connector, but that set up would extend over 2.5" out from the mast and is frankly more robust/clunky than I need. I finally stumbled onto M12 connectors. I have found very few sailing related references to M12 connectors. Any idea why they don't seem to be used? They are IP67. They seem like they would work. They are sold for corrosive environments. 4A, 250V. My lights are now all LED bulbs. Perhaps the connector won't stand up to the outdoor elements (I'm in fresh water though)? I have attached pics of the 4 pin receptacle I am thinking of installing in the mast and the plug that I'll connect to the wires from the cabin. I'll use an identical 5 pin set up for the wind transducer. One Issue I have identified is the reference to 18AWG max wire size. I'm hoping I can get away with 3 individual 16 AWG power wires and possibly a 14AWG ground (if 16 is inadequate).

Do you think this M12 connector set up will work? Thoughts on whether I need a shielded connector for the wind transducer connector? I can always try it and see if it works - I just thought I'd seek the collective wisdom here.

Thanks for your advice.


TE panel mount 4 pin.jpgTE female plug 4 pin.jpg