Need help connecting EMEA GPS to Seatalk interface box

[maej]

I have an Evermore SA-320 GPS that I want to connect to a Raymarine E85001 interface box to get SOG etc to the other instruments on the Seatalk network. Trouble is the instructions for the gps are cryptic and use different terms from the interface box so I am left confused about what wire goes where. Can anyone help?

There are 5 GPS wires, described like this in the document...

No power on shield!
BLACK: VCC Power Ground
RED: Power Supply
WHITE: RS-232 data Minus (TX-)
OR
BLACK: RS-232 data Minus (TX-)
GREEN: RS-232 data PLUS (RX+)​

The Raymarine interface box has NMEA IN (+ & -) and NMEA OUT (+ & -), with Red, Yellow and Screen for Seatalk.

I imagine I can connect the GPS black to the Seatalk screen and the GPS red to the Seatalk red to power the gps, but where to connect the remaining wires I have no idea, and the instructions seem to say that the black and white wires are both TX- while the black is also power ground.

Thoroughly confused

 

[prv]

The list you have there is either wrong or incomplete. Confusingly, when I googled for this GPS, the PDF I found had two options which were different again (they show the power supply negative as green and the TX+ as brown).

You need to connect the TX- (whichever colour it turns out to be) to the Raymarine NMEA IN - and the TX+ to the NMEA IN +.

I'm not sure I can help with figuring out which wires those are, though.

Pete

 

[JohnGC]

I have an Evermore SA-320 GPS that I want to connect to a Raymarine E85001 interface box to get SOG etc to the other instruments on the Seatalk network. Trouble is the instructions for the gps are cryptic and use different terms from the interface box so I am left confused about what wire goes where. Can anyone help?

There are 5 GPS wires, described like this in the document...

No power on shield!
BLACK: VCC Power Ground
RED: Power Supply
WHITE: RS-232 data Minus (TX-)
OR
BLACK: RS-232 data Minus (TX-)
GREEN: RS-232 data PLUS (RX+)​

The Raymarine interface box has NMEA IN (+ & -) and NMEA OUT (+ & -), with Red, Yellow and Screen for Seatalk.

I imagine I can connect the GPS black to the Seatalk screen and the GPS red to the Seatalk red to power the gps, but where to connect the remaining wires I have no idea, and the instructions seem to say that the black and white wires are both TX- while the black is also power ground.

Thoroughly confused

If I've found the correct information for these two items;
http://www.mesltd.co.uk/files/gps105man.pdf
http://www.raymarine.eu/WorkArea/DownloadAsset.aspx?id=2301

Then you won't be able to get the GPS data to Seatalk.
The GPS outputs data in USB and RS232 format.
The E85001 doesn't have a RS232 input.

You may have different versions to the ones I've found, with more input/output options.

 

[prv]

You may have different versions to the ones I've found, with more input/output options.

Yeah - I found another PDF for the SA-320 which lists a completely different set of colours:

http://www.starnavigation.de/SA-320_V2.4_Spartechnik.pdf

Wire Color Designation
Red VCC, Power Supply ( VDC 5V)
Green RS-232 Transmit Tx, Output Signal
White RS-232 Receiver Rx, Input Signal
Black Ground


It seems to be a real mess...

I think the RS232 thing *may* be a red herring though as an NMEA input might accept it although it's not strictly correct, but I'm hazy on the low-level details.

Pete

 

[Bru]

Early NMEA0183 equipment used the RS232 serial hardware standard , later the standard was changed to RS422

However, most of the time RS232 and RS422 hardware is interchangeable (although it shouldn't be really)

NMEA0183 is a data protocol that runs over RS232/422 serial hardware by the way

To answer the OP's question you need to connect the RS232 signal out positive to the Seatalk NMEA In positive and the negative to the negative

 

[Andrew G]

Hi Maej, I am literally completing the installation of an E85001 as soon as the weather improves (it is working but not prettied up). You don’t say what version of GPS you have (ie USB or bare wire?) and what wire colours you have?
Just confirming that you want to input your GPS’ output as NMEA In to the E85001 and take SeaTalk out of the E85001 to feed your SeaTalk network – yes?
Looking at the E85001 as per the manual the NMEA In is bottom right and, as Erbas said, your GPS’ NMEA signal + and - go in there. Assuming your SeaTalk network already has power (and is fused) the SeaTalk network’s red, black/screen and yellow go to the SeaTalk out (middle left on E85001) as per the attached. Cheers, Andrew

 

[prv]

Hi Maej, I am literally completing the installation of an E85001 as soon as the weather improves (it is working but not prettied up). You don’t say what version of GPS you have (ie USB or bare wire?) and what wire colours you have?
Just confirming that you want to input your GPS’ output as NMEA In to the E85001 and take SeaTalk out of the E85001 to feed your SeaTalk network – yes?
Looking at the E85001 as per the manual the NMEA In is bottom right and, as Erbas said, your GPS’ NMEA signal + and - go in there. Assuming your SeaTalk network already has power (and is fused) the SeaTalk network’s red, black/screen and yellow go to the SeaTalk out (middle left on E85001) as per the attached. Cheers, Andrew

I think we can assume it's not the USB version, as that's a non-starter for this purpose. Everything else has already been said, but the trouble is that there seem to have been several versions of the GPS with different wire colours, and the documentation he has for his one doesn't make sense (no TX+, two possible options for TX—).

Pete

 

[maej]

Thanks all for your advise so far. The gps is one of these http://www.ebay.co.uk/itm/370781324114, it is the bare wire version (not usb) which I chose based on some recommendations on this forum. It came with a wiring diagram leaflet like this...

Ultimately I just need to know which 2 wires from the GPS to connect to the NMEA IN + and NMEA IN - on the Raymarine box.

The diagram showing a TX minus but no plus, and an RX plus but no minus is my problem. My first thought was to connect the white TX- from the gps to the NMEA IN + of the box, and the shield of the gps to the NMEA IN - on the box, but when I powered it up the box failed to do anything, none of the leds lit up and no data. It was powered, I checked. I assumed either the box was already dead or I had just blown it up, so I've got another one now to try and want to get the wiring right before I power it up this time, those boxes are expensive.

 

[Andrew G]

(Edit: Upon reflection I think PRV is right that there may be an issue with the documentation - what are the differences in the two schwarze's (blacks) one is "schwarze" the other "schwarze Schirmung" (=Black Shield) in the pic it looks like one is a shield - use it last? If you connected the wrong black you may have blown it up but I wouldn't rush to that view yet.
I'm tempted to suggest Green to NMEA In +, and White NMEA In - and if that doesn’t work Black (shield) to NMEA In -). I defer to PRV’s experience!

 

[maej]

... what are the differences in the two schwarze's (blacks) ...

The only visible difference between the 2 blacks is that the insulation on the shield stops about 2mm short of the main cable insulation.

Is there any way to test which wire is which using a multimeter if I apply power to the gps? Will a multimeter show voltage on just the actual wire sending the NMEA data for instance?

 

[prv]

Connecting NMEA wires wrongly shouldn't blow anything up, it just won't work. The forum is full of threads with clueless old men sucking their moustaches and connecting all the wires up at random - if this regularly caused damage we would hear about it.

Thanks for posting the particular documentation you have, complete with error.

If I was installing this, I think I might guess at the following:

Green = NMEA + / white = NMEA - (on the basis that NMEA input doesn't make much sense for a simple GPS puck, and they've mislabelled the green wire as RX when it should be TX)

I strongly suspect that the above is the right combination, but if it didn't work I might try:

white = NMEA + / shield = NMEA - (perhaps it does have an RX after all, for programming or something, and the error was mislabelling white as TX - instead of TX +)

(I'm slightly puzzled by the mention of LEDs on the Raymarine interface box, as mine doesn't have any, but perhaps they're different models.)

Pete

 

[maej]

... (I'm slightly puzzled by the mention of LEDs on the Raymarine interface box, as mine doesn't have any, but perhaps they're different models.)...

Mine (both of them) are E85001, different issue letters but visually look the same. There appears to be 3 surface mount LED's on the circuit board labelled something like "Raytech", "Seatalk" and "NMEA" which I assumed to be power, seatalk data and nmea data. There's no externally visible LED's on the box, just those 3 things that look like surfact mount LED's on the board.

Bottom right of this picture...

 

[prv]

Mine (both of them) are E85001, different issue letters but visually look the same. There appears to be 3 surface mount LED's on the circuit board labelled something like "Raytech", "Seatalk" and "NMEA" which I assumed to be power, seatalk data and nmea data. There's no externally visible LED's on the box, just those 3 things that look like surfact mount LED's on the board.

So there are. I'm not sure whether mine has those or not, I've not looked closely at the board. Mine is quite old though.

Pete

 

[Bru]

Minor correction on the LED assignments - RayTech will refer to the (proprietary) RS232 serial interface (to a PC running RayTech software)

prv has hit the nail firmly on the head connections wise, if that doesn't work the only viable tool for diagnosing it further is an oscilloscope

It might be of interest and relevance to note that the application of said tool diagnosed the probable reason for our AIS receiver not talking to our NMEA multiplexer - the AIS receiver is only kicking out +2.4v on the signal peaks and the minimum for RS232 is +3.0v and for RS422 it's nominally 5.0v (although it's not quite as simple as that om 422 but that doesn't matter here). The key point is that it's entirely possible that you've got it connected up right but the two pieces of hardware are talking a slightly different language and don't want to communicate

 

[Bertramdriver]

After fiddling around with the same problem I came to the solution by running the evermore output down to the NMEA input into the chartplotter RM RL80 (TX+& TX-) and then taking the seatalk to the rest of the system from the seatalk slot in the back of the RL80. Power fed directly to the gps. Now works perfectly

Ps what did not work was trying to feed the NMEA output from the gps directly into the NMEA input on the autopilot. Zero response, so I reasoned that the gps output needed to be reprocessed into a signal recognised by the autopilot. Hence the use of the chartplotter to translate and distribute the seatalk.

Now I have a similar problem on my raymarine VHF, complicated by the use of a Garmin Gps receiver which I run on a separate system. Fun isn't it!

 

[maej]

I just want to update this thread with the final working combination in case anyone else has this issue in the future.

prv was absolutely correct with the below wiring.

...
If I was installing this, I think I might guess at the following:

Green = NMEA + / white = NMEA - (on the basis that NMEA input doesn't make much sense for a simple GPS puck, and they've mislabelled the green wire as RX when it should be TX)
...

So in full, the 5 wires from the GPS were connected like this...

GPS RED = 12v positive -> Connected to the seatalk red along with the red wire from the seatalk cable.
GPS BLACK = 12v negative -> Connected to seatalk white along with the seatalk shielding (negative) wire.
GPS GREEN = NMEA positive -> Connected to the "IN NMEA +" connection.
GPS WHITE = NMEA negative -> Connected to the "IN NMEA -" connection.
GPS SHIELD (also partly black) -> This I insulated and left unconnected.

When powered up the seatalk and nmea leds light up inside the box and soon after GPS data was available on the seatalk network, specifically SOG on my log display.

Thanks prv and all for your help.

 

[prv]

Glad it worked. Just takes a little experience of the kind of documentation mistakes likely to be made by Chinese ebay sellers

Since we're updating things for the record, I happened to be rewiring my interface box the other day and I checked whether it had the LEDs mentioned upthread. I can confirm that it doesn't.

Pete

 

[nigelmercier]

... GPS data was available on the seatalk network, specifically SOG on my log display...

So the bottom line is you have connected the SeaTalk bus and NMEA to the NMEA input on the box?

What log do you have? I've got the same interface box, but it only seems to do SeaTalk to NMEA.

I will have to double-check how I wired it, I may be missing an unexpected bonus.

 

[prv]

What log do you have? I've got the same interface box, but it only seems to do SeaTalk to NMEA.

I'm pretty sure it's designed to accept NMEA data onto the Seatalk bus, otherwise what would be the point of the NMEA IN port?

Pete

 

[Bru]

I'm pretty sure it's designed to accept NMEA data onto the Seatalk bus, otherwise what would be the point of the NMEA IN port?

Pete

Yep, it is.

With a GPS or plotter NMEA OUT connected to the NMEA IN on the convertor, COG, SOG etc is available on the Seatalk bus to any instrument that can use it