I have Nmea 2000 temp data that i want to control a relay with for digital hot tub temp control on a 68' sailboat with a hot tub.
Can someone point me in the correct direction...?
Scott
Please give examples of that data. The actual message and where are you connecting to get that data. How often does the data arrive, or do you have to ask for the message by sending a different message. I know NMEA is the marine equivalent to the automotive control message system.
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I think it would be easier, cheaper and possibly better to control the hot tub with it's own temperature sensor.
What would be the advantage of using the NMEA sensor over a dedicated sensor?
I guess a water temp sensor is inevitably needed, but is this additional sensor used to adjust the water target temperature based on air temperature, for increased comfort?
Arduino Nano to parse the NMEA data sentence and control relay using a motor driver board or FET breakout. Should be pretty straightforward.
its own sensor is not very accurate and has too much spread on and off of about 3 degrees.
my Digital Nmea temp sensor is up stream from the heater and much more stable and the actual water temp of the tub water.
I will look as soon as I get a chance what the data actually is and timing which i can adjust i think. I have never worked with Arduino before so please be kind not sure really where to start.
This is a 5000 to 6000 watt heater, 35 year old setup on a 68' sailboat,
6 person Hot Tub behind the center cockpit. . I have added flow sensor to the overheat control and temp control knob. I now have Nmea digital temp of the hot tub on my Nmea 2000 network which i display full screen on 16" Navigation MFD @ The hot tub just want to use that temp reading to control a relay to control my heater on top of the safety controls etc.....
It looks like i may want to use a CAN-BUS Shield v2 with a Arduino Uno Rev3 or Arduino Mega 2560 Rev3 or Arduino Leonardo with Headers.....????
Why CAN bus? Is NMEA-2000 physical layer CAN? Previous version was just RS232.
Is any of your NMEA stuff made by Maretron?
You did not mention that the tub has another sensor other than the NMEA sensor.
When I said "it's own sensor" I was thinking to add a new sensor that would be connected only to the Arduino. A DS18B20 sensor would be very accurate, easy to use with Arduino and waterproof versions are available.
I would recommend to use an Arduino Nano V3 which is a good Arduino for a beginner to use when building a prototype circuit on breadboard and soldering up a final circuit on stripboard.
Most all of it is maretron
I thought NMEA is basically same as can bus...
Taking a closer look, NMEA2K is based on J1939. So yes, its CAN at some levels.
Interesting. The founders of Maretron were all automotive electrical engineers. Their headquarters was in Phoenix, AZ. One bought a ranch in Central Oregon, Redmond, to be exact. His job was to build a factory to produce the devices. Phoenix did the engineering.
My electronic assembly service was in Redmond and they found us to build their circuit boards. They also used a company in Bend, Oregon. Wonderful people to work with. I particularly remember the GPS receivers. Users insisted on placing them in front of RADAR antennas! Maretron finally gave up trying to get customers to stop doing it and added a metal shield fence weaving it's way around all the sensitive components. We used a CNC soldering machine to do all the soldering. Also the GPS used a receiver from China that we bought in tape and reel format. I think it was 1,000 per reel at a cost of $5.00 each receiver.
am a newbie, and I have a project.
Want to read a NMEA 2000 temperature over Can Bus and control a relay that will control a heater.
This is for a Hot Tub on 68' Sailboat. i would like to adjust and control things with a display, mobile phone and maybe also widget for lack of better word for NMEA 2000.
if >=104degree for 1000 ms turn relay off
if <=103 degree for 1000 ms turn relay on
Anybody interested in helping?
I have several different arduino's on their way to me with a couple of can bus transceivers, power supply, breadboards, jumpers etc.....
Scott
Why are you starting over?
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