NMEA 2000 Drop Cable 20m ?

[Jokani]

I am planning to install an NMEA 2000 Maretron wind transducer at the top of the mast this winter.

The mast is 14m, as I cannot find a 15m cable I plan to use 2 separate cables, a 10m joined to a 5m.

That will get me inside to just below the mast, I'll then need an additional 5m cable to get me to the NMEA 200 backbone - I always planned to have a join here to make it easier whenever the mast is next removed.

So in total, I intend to have 20m drop cable in 3 sections.

I have read online that joining 2 cables together is OK, but I can't find any reference to 3 cables.

Any advice is gratefully received.

 

[PaulRainbow]

Max length for a drop cable is 6m, doesn't matter how many joins there are.

N2K mast head wind units usually have an interface below decks, or if true N2K they should be at the end of the network, ie part of the backbone, and have integrated terminators. If integrated terminators, the 6m cable length is not applicable, neither is the amount of joins.

 

[Jokani]

Your advice is appreciated, thank you, prompted me to find this which further clarifies:

 

[PaulRainbow]

Your advice is appreciated, thank you, prompted me to find this which further clarifies:

View attachment 185388

There you go, just connect it to one end of the backbone. Cables are available in 20m lengths, if need be.

 

[KompetentKrew]

You might also look at the LCJ Capteurs CV-7, which is also an ultrasonic masthead unit, if you haven't bought this one yet.

The CV-7 is NMEA 0183 down the mast and then it has an NMEA 2000 adaptor that also includes a barometer. So you don't have to worry about the length of the drop cable, and the NMEA 2000 network can continue forward of the mast. The CV-7's NMEA 0813 to 2000 adapter just connects directly to an NMEA 2000 T. It's a comparable price to the Maretron, maybe a fraction cheaper.

 

[Jokani]

Thanks fro the advice, much appreciated!

 

[tjbrace]

You might also look at the LCJ Capteurs CV-7, which is also an ultrasonic masthead unit, if you haven't bought this one yet.

The CV-7 is NMEA 0183 down the mast and then it has an NMEA 2000 adaptor that also includes a barometer. So you don't have to worry about the length of the drop cable, and the NMEA 2000 network can continue forward of the mast. The CV-7's NMEA 0813 to 2000 adapter just connects directly to an NMEA 2000 T. It's a comparable price to the Maretron, maybe a fraction cheaper.

I have this. It has been a ‘fit and forget’ transducer. Great piece of kit.