NMEA connections RJ45?

[smonard]

Hi Guys.

My electronics on the boat are connected together by the data wires being soldered together and covered with heat shrink tubing. This is OK until you want to change something or remove something or want to take stuff home for the winter. Has any one made a system with like an ethernet patch panel with all the NMEA instruments connected with RJ45 connectors. Would the power wires need chunkier connectors due to the higher current? My Easy AIS has a RJ45 on the AIS end. I'd like the VHF, chart plotter, AIS and tillerpilot to be easily connected and disconnected. The power to the tillerpilot would have to be separate of course. The radio already has separate power wires, could RJ45 connectors handle an amp or two?
Thanks for any input.

 

[fireball]

I did - but the units I wanted to connect had power connection too - and the RJ45 plug was just too small to accept the cable size. So after a failed attempt I abandoned the idea for the chart plotter - however, I do have it in place for the Yeoman - so far it works very well ...

I don't think I'd use it for the VHF or Tillerpilot - as you correctly question - the ability for the RJ45 to handle the amps!

 

[electrosys]

If I were in your position, I'd make-up a custom panel using a series of DB-25 (or 15) connectors. Gold-flashed contacts are rated at a nominal 5A, athough for ground and any power leads, I'd at least double-up the number of pins used. And use solder-bucket, not insulation-displacement.
These connectors are not waterproof of course, but in a cabin this shouldn't matter.

 

[smonard]

If I were in your position, I'd make-up a custom panel using a series of DB-25 (or 15) connectors. Gold-flashed contacts are rated at a nominal 5A, athough for ground and any power leads, I'd at least double-up the number of pins used. And use solder-bucket, not insulation-displacement.
These connectors are not waterproof of course, but in a cabin this shouldn't matter.

Those look good, a couple of cables go though small holes in the bulkhead but those could be enlarged. The tillerpilot is the power hungry one but I would connect the power wires directly to the fuse panel and just use the electronic connectors for data.
How about a DB-15 from the plotter to the panel (an SD CP300 it has about 8 wires) and RJ45s for data to and from it or the smaller DB-9s
My biggest difficulty with all this wiring stuff is the wire colours, I'm afflicted with RG colour blindness!

 

[electrosys]

Another possibility would be the RS 'QM Multipole' range of connectors - made by ITT-Cannon - they're kinda modelled on the military standard connector, but at half the price.

To see these, dial-up: http://uk.rs-online.com/web/
and search for 474-502
this will then take you to a example socket, and from that page you can then download a .pdf file of the whole range.

Being circular, hopefully they won't require you to cut any enlarged oblong holes !

With regard to R-G blindness (bummer ...) the only thing I can suggest, is to get a mate not so afflicted to attach small cable identifiers (markers) to the R-G leads. They can be bought - but for the few you need - if you can get hold of some cable with Black and White insulation (quite common in The States, I believe), then short lengths of stripped-off insulation slid onto your R-G leads might do the trick. Or tags made from coloured tape.

 

[aluijten]

Don't use RJ45. These were never meant to be used for frequent reconnecting. Also not meant for much power to be transferred.

On a previous boat I've made use of XLR connectors. These are designed for the harsh life of PA systems (like for musical bands at live performances). These connectors can handle a lot of mis-use and power. There is a variety of versions available, with chassis parts, male/female and 2 to 8 pins per connector. They are made of metal and have a autolocking system to prevent plugs from disengaging. Never had any problems with them. Any decent electronics-parts shop sells them.