NMEA cable

[Ray_G]

I have just installed AIS (Vesper Watchmate) and need to connect the Plotter for GPS information. Unfortunately one instrument is at the chart table and the other is cockpit mounted so the nmea wiring is going to be a long run, perhaps as much as 10 metres.

What wire should I be using (nmea 2000) and where can I get it from?

Advice would be appreciated.

 

[Playtime]

I have just installed AIS (Vesper Watchmate) and need to connect the Plotter for GPS information. Unfortunately one instrument is at the chart table and the other is cockpit mounted so the nmea wiring is going to be a long run, perhaps as much as 10 metres.

What wire should I be using (nmea 2000) and where can I get it from?

Advice would be appreciated.

The magic of Google. Try these people.

It may be overkill, though.

 

[David2452]

If its NMEA 2000 then you can get a ready made lead and a "T" to tap into your backbone from any Garmin dealer (or me come to that), they come in varying tengths and all the N2K plugs are of a standard design, actually if you do not already have an N2K backbone you will have to start one, not such a biggy, all you will need is the cable already mentioned, a couple of "T", a male and female terminator and a power tap "T". I see you are in Suffolk, if you are close to Shotley I could have a look or advise.
Are you sure it's N2K? I thought it was an 0183 listener, in which case I stock the right screened twisted pair stuff too.

 

[Ray_G]

Ooops, you are right David - it is indeed 0183. So, does any twisted wire do?

 

[David2452]

Something around 28 to 24 AWG would be ideal, it should be screened multi strand and tinned twisted pair for reliability, connect the screen drain wire at the "talker" end only.

Edit to say it should be 22 AWG. Also if it is 0183-HS it will require a third conducter to ensure the common mode ground potential is equal at drivers and recievers.

 

[chrisgee]

Something around 28 to 24 AWG would be ideal, it should be screened multi strand and tinned twisted pair for reliability, connect the screen drain wire at the "talker" end only.

Edit to say it should be 22 AWG. Also if it is 0183-HS it will require a third conducter to ensure the common mode ground potential is equal at drivers and recievers.

Would Cat5e screened do? I `ve got loads of it and need to do a similar job to the OP

 

[David2452]

Cat 5e is unfortunately just too light as the conductors are 24 AWG, it will probably work but I would not even consider using it unless it were tinned and the joints are moisture sealed.

The specs I use are for optimum performance, reliability and longevity, you could use almost anything including 3 seperate cables of cheap old low strand stuff and it will almost certainly work, it's a case of how well and for how long and how it would be affected by and cause effect to other kit.

 

[ianj99]

Cat 5e is unfortunately just too light as the conductors are 24 AWG, it will probably work but I would not even consider using it unless it were tinned and the joints are moisture sealed.

The specs I use are for optimum performance, reliability and longevity, you could use almost anything including 3 seperate cables of cheap old low strand stuff and it will almost certainly work, it's a case of how well and for how long and how it would be affected by and cause effect to other kit.

Cat 5e is more than adequate for a 10m run. 4800baud is hardly a demanding speed, nor even would 38k be.

 

[JeffRobbins]

Cat5e should work fine if it has stranded conductors. Shielded would be best. Tinned is highly recommended for marine, but I don't know if this is typical in normal Cat5e. The RS-422 (eg. NMEA-0183) spec recommends 24AWG for most installations. NMEA-0183HS is the same but operates at 38,400 baud.

Checkout http://www.bb-elec.com/tech_articles/cable_selection.asp

Jeff Robbins
Vesper Marine

 

[David2452]

NMEA 0400 standard does not recommend 24 AWG, it specifies and insists on it, furthermore it specifies and insists on minimum 95% shielding and multi strand, twisted and tinned, that the shield should be grounded at the talker. Anything else is not compliant and could not be signed off as compliant by any NMEA certified installer. As I have said before, it’s not a case of what will work, it’s a case of what will work best. It's not even about cost, 10m of the right stuff costs me about £8.00

 

[ianj99]

NMEA 0400 standard does not recommend 24 AWG, it specifies and insists on it, furthermore it specifies and insists on minimum 95% shielding and multi strand, twisted and tinned, that the shield should be grounded at the talker. Anything else is not compliant and could not be signed off as compliant by any NMEA certified installer. As I have said before, it’s not a case of what will work, it’s a case of what will work best. It's not even about cost, 10m of the right stuff costs me about £8.00

NMEA 0400 provides voluntary standards that clarify and define competent installation practices applicable to vessels from 20' to 150' and up to 300 gross tons. ....

The intended application of this NMEA standard is for vessels that will use large and sophisticated systems of marine electronics for communication and navigation purposes

I'd like to see anyone prove that using 10metres of 24swg twisted pair cable causes erroneous nmea data .... Gilding the Lilly comes to mind..

 

[David2452]

Lillies do look nice in gold, and it's a nice protective layer too.

 

[ianj99]

Lillies do look nice in gold, and it's a nice protective layer too.

I've passed your comments onto Garmin because my GPS16HVS gps module is supplied with 10M of 8core 28awg (about 30swg) cable!
I'm sure they'll want to recall them and fit the correct cable..

 

[David2452]

I've passed your comments onto Garmin because my GPS16HVS gps module is supplied with 10M of 8core 28awg (about 30swg) cable!
I'm sure they'll want to recall them and fit the correct cable..

Well, they've already had to do it once with some non compliant cables, so............