SignalK, measuring temperature

Updated 2023-11-05 !

An introduction to the SignalK, Marine application, is given here.

A very easy way to measure temperature with Raspberry Pi, RPi, is to connect one wire (1W) DS18B20 (DS)temperature sensors direkt to the RPi GPIO.

Here You find a post where the temperatures are transfered via WiFi

Seatalk 1 and NMEA2000 combined

Updated 2023-01-20 !

Our boat was delivered, 2006, with just Raymarine equipment using network Seatalk 1(ST1), and some NMEA0183(N1). Updates and additional equipment will use the newer NMEA2000(N2K). We will keep the two well functioning Raymarine 12”, E120, and the radar. In addition, for Navigation purposes, we use the iPad app iSailor.

The easy way to combine ST1 with N2K is to use the Raymarine Seatalk 1 to Seatalk NG(STNG) converter, Raymarine E22158. STNG and N2K is the same protocol, with some dialectal differences, but have different cabling.

Don't miss this post where I'm presenting additional solutions, including a NMEA WiFi gateway, and add ons.

NMEA 2000 temperature sensor, wet exhaust

In former posts I used the temperatur sensor DS18B20, in several applications, but now it was time for the boats exhaust temperature and checking out YDTC-13 from Yacht Devices(YDTC). (But please note that the YDTC can be used in any temperature application.)

When you are boating, using the engine, it's very important that the cooling water always is present otherwise major damages can follow. In "wet exhaust" systems it's easy to get the temperature which I posted here.

Volvo Penta NMEA 2000 Gateway

Updated 2021-06-15

It's always nice to have ALL information at the same place, navigator/plotter, when You are out with the boat. 

What could be missing is the engine information/data. If You have a Volvo Penta from 2006 or later it could be pretty easy.

There are some "standard" NMEA 2000 gateways to choose from, for example; 

• Volvo Penta has it's own 22813366, 3889758
• Raymarine ECI-100
• Maretron J2K100
• .....

Raspberry Pi measuring Voltage

I'm always a little confused that as soon as someone wants to get an analog measure to a Raspberry Pi(RPi) they are often taking a detour via an Arduino/ESP or some other microcontroller. 

Why not just take an Arduino peripheral and use it together with a RPi ? 

In my case I needed to measure the voltage across a fresh water tank level sensor in our boat, but i could be any DC voltage. Hints for sending the data to a Signal K(SK) server is found below. 

In this post I will use an ADS 1115(AD), or ADS 1015, as AD converter.

SignalK, measuring temperature II

An introduction to the SignalK(SK), Marine application, is given here.

A very easy way to measure temperatures with SK is to use one wire (1W) DS18B20 (DS)temperature sensors. 

In a former post the DS:s where connected direkt to the RPi GPIO:s, but in this post they are WiFi enabled via the Shelly 1(S1). Alarms are also sent when the temperature exceeds a set value.

If humidity is of interest You can use a  DHT22 sensor instead of a DS sensor.

OpenPlotter, V1, quick install guide

Updated 2020-01-13 !

OpenPlotter is;

• A complete boat navigation system
• Includes OpenCPN, Chart plotter navigation
• OpenSource, so it's free !
• Running on Raspberry Pi(RPi)
• Its hardware is cheap
• Running on Unix, so its reliable

I really don't recommend this old OP 1, instead check out OP V2, stable, which works very well ! 

Boat navigation network

In a former post a I presented our approach to mix a modern NMEA 2000(N2) network with the older Raymarine ST 1 network, installed 2006.

During the Years it has grown and been added with new functions. The pictures to the right is the actual layout.

The first add on was a N2 GPS described here.

OpenPlotter V1, NMEA data TO file

Updated 2021-12-14

A newer post in the same subject !!

Sometimes You want to "take home" Your latest trip on sea and "replay" it or replay it doing some changes in the settings for the OpenPlotter or OpenCPN applikation and se the result direct.

One way is to create log files with the the "raw" NMEA data and then use them at home with tips from this post.

Creating log files from NMEA 2000 bus, N2K, is the most straightforward.

OpenPlotter V1, USB sensors install

Updated 2018-06-26!

If You started with my quick instal guide You are a little familiar with OpenPlotter, (OP), basics and now we proceed with the sensors. Don't forget to delete the RMC sentence from the "NMEA 0183 generator" which we used.

Link to a stand alone AIS receiver.

Not valid for OP Beta V2 !!  Check here !

NMEA2000 GPS added

Adding a NMEA2000 GPS and add an additional cable to E120

So what happens when You add a NMEA2000, N2K, GPS to the network ?

Nothing much actually. No conflicts. The E120 is still "hocked" on the old Raymaring RS125 GPS and the Garmin GMI 10/20 shows the info from the new NME2000 GPS with some additional data compared to the old GPS.

The chosen GP:s is Garmin GPS 17X because it was on sale for just 20 €.  It is mounted behind the instrument panel.

The picture shows the GPS at the right and the ST converter in the upper part

Network diagrams

Network diagrams Seatalk 1, Seatalk HS, NMEA0183, NMEA2000

To get en idea how the network is configured please find the links below

The diagrams are divided into a Raymarine part, Seatalk/NMEA0183, and a Garmin part, NMEA2000

The respective diagram is vertically divided in 3 parts depending on location.
Helm, tecnical storage room and flying bridge

Boat network ST1, NMEA0183, ST HS

Boat network NMEA2000