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8v92 Digital Engine Data Conversion

  • Thread starter Thread starter rustybucket
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I believe the pgn's for many factors are already defined. Temp is not an issue for multiple areas or devices.I'm asking why reinvent the wheel?
Well, really, to my knowledge this wheel has not been invented...? Are you aware of any solution that accomplishes All I have discussed?

Really the question, why reinvent the wheel.... I mean, isn’t that kinda stifling to innovation? I’m not trying to reinvent the wheel, trying to make a better wheel that rolls my way.

This project isn’t so much about getting the engine data digitally, more so what you do with the data after acquisition.
 
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Maretron and others have temp sensors for anything from freezers to get.

Theyre programmable an support putting data onnmea2000 displays.

I know I can get my garmin screens to do a.c. and dc voltages and charger inverter information too.
 
Maretron and others have temp sensors for anything from freezers to get.

Theyre programmable an support putting data onnmea2000 displays.

I know I can get my garmin screens to do a.c. and dc voltages and charger inverter information too.

Maretron basic system runs around $5k, the intermediate system is right at $20k.

The 'basic' system gives you engine data, tankage and bilge pumps. But to me the maretron data displays are very hokey and not very well done.

I'm sorry, but this looks like 1992
Engine Pressures and Load.jpg


Currently I have all engine temp data displaying, will be hooking up the boost and pressure sensors next time down.

So, I am VERY close to having everything that the 'basic' maretron system has... and I've spent less than $200.

For example, Maretron EGT Probes are $115/ea, so $460 in EGT sensors for these engines. I paid $15/ea for my EGT probes, so $60 total for both engines. So, are the Maretron EGT sensors better? Possibly, but are they $400 better? My bet is probably not. Both sensors have virtually the same specs and look almost identical.

When I'm finished with this project I'll have everything the 'intermediate' maretron system has....and more... and I'll have spent under $1000.....

Don't get me wrong, I'm far from cheap, and I sure don't mind spending money (just installed a 25kw 6' Garmin radar a couple weeks ago), but I can think of about 19k reasons to not go with the maretron unit at this time ;)

And again, I do not really care to show any of this data on my Garmin. That screen real estate will be consumed with navigation, sonar and radar. But as stated earlier, it's very easy for me to output this data in whatever format is necessary in the future.
 
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Here is a rough project spec sheet that this device will accomplish. Maybe this will help clear up why this system is somewhat different than others.


- All data and data screens available via wifi, no hard wires ran to bridge or other areas (other than to power the displays)

- Supported devices: Literally any device that has wifi, web browser and a screen. Including but not limited to: Ipad, iPhone, kindle, Android phones, any other smart phones with a web browser, tv's (with wifi and web browser).

- Device alerts: Any device connected to the network will receive alerts, visual and audio alerts should an alarm be triggered.

- No internet connection required - You do NOT need to have internet connection or cell service for this to function properly.

- Engine Data: System can read both digital and analog sensors. Pressures, temps, Thermocouples, tank levels, bilge levels, fuel flow...etc

- Boat System Data: Electrical system monitoring, shorepower monitoring, battery levels, engine room temp, cabin climate levels (humidity, temp...etc)

- Satellite Texting: The system uses a Satellite SMS texting module to send text messages via satellite. This allows you to communicate with friends/family while at sea. It also allows the boat to communicate with you. For instance if a high bilge alert is triggered it will use the Satellite SMS to send your phone a text alerting you of the issue.

- Cellular Texting: The system can send cellular messages for alerts as well. So, while at the dock in good service area, you may wish to disable the Satellite SMS messages to save cost.

- SSB Email: Very much in development phase of this, but the gist is using SSB to send basic emails.

- Weather Station

- Internet connectivity via wifi or cellular service (LTE or 3g) when within service areas.

- System updates via internet connection or SD card.

- Open Source: Anyone with the system can modify the displays/layout and the data shown. They can also add in additional modules not included.

- Data formats the system will be able to output (and consume): NMEA0183, NMEA2k (at some point), SAE J1939, signalk, JSON and others.

- Data Logging - Data logger can be enabled to log data over time. For instance you could log data for an entire trip, then review the data in charts/graphs...etc, or export it for review in other programs like excel.
 
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What works for you is fine. My issue is servicability after you sell the boat. Its not a standard and the cost vs time may not offset the savings down the road.

I have j1939 systems on engines that can display on their dedicated displays and interface with the new mfd screens too.
 
Its not a standard

You've stated this several times now, and honestly after my responses it confuses me. If the system can output nmea or j1939 how is it not a standard?

On your engines (not knowing what they are), the sensor passes it's data to an ecu somewhere, and that ecu converts the sensor data (just a voltage or resistance) to a digital data (a readable number 120deg or 55psi), then makes that data available in a 'standard' format, j1939 in your case. No sensor outputs j1939 or NMEA2k, they rely on a computer somewhere to interpret and convert that data to the applicable format.

No engine system data is 'Standard'. It is nothing more than sensor data interpreted, converted and output in a standard format for other devices to consume.

If my device takes the sensor data, converts it and outputs it in standard format(s) for other devices to consume, how is it not 'standard' by your definition?

If the ecu goes out on your engine (or on a maretron system), you have to order a new one from the mfg, wait for it to be installed (most likely be a service tech), resulting in a bill of several $k. If my ecu goes out I have a spare on hand (b/c they only cost $50). I pull the SD card (RAM), plug it into the new ecu, plug a serial connector in and we are back up and running.

Every system you have mentioned is not 'standard'. They all have their own proprietary code and systems. However they do all output in a 'standard' format. Just like my system will.

However... My system will also output in a much more widely readable format of www. My system will not require that you have a $5k marine display everywhere you want to view said data. It is very much an open system, inviting users to supply their own displays whether it be the iphone in their pocket, or a fully marinized touch screen display. I don't want you to have to spend $20k in displays just so you can see YOUR data in the cabin, stateroom, engine room, galley....etc. I want you to be able to see YOUR data anywhere and on anything you want to see it on.
 
You've stated this several times now, and honestly after my responses it confuses me. If the system can output nmea or j1939 how is it not a standard?

...........

However... My system will also output in a much more widely readable format of www. My system will not require that you have a $5k marine display everywhere you want to view said data. It is very much an open system, inviting users to supply their own displays whether it be the iphone in their pocket, or a fully marinized touch screen display. I don't want you to have to spend $20k in displays just so you can see YOUR data in the cabin, stateroom, engine room, galley....etc. I want you to be able to see YOUR data anywhere and on anything you want to see it on.


I missed earlier that you were planning to output standard protocols. This is neat. I'm doing this project before the boat goes back in the water. I was planning on using Chetco. For me, the worry is robustness. I want something that is indutrial with a solid case and good terminal strips etc.

Using Wifi for primary display of engine data is a no-go for me.

I was going to do Chetco to nmea2000 then buy a cheap 8inch simrad screen for $450 (includes chart plotter and built in GPS) and use that cheap screen (daylight readable) for my nmea2k engine data. Big fancy screens reserved for radar/chart/etc.

Also, your senders may work fine, but I'd be weary to trust epoxy to hold the sensor bulb in place with vibration etc. Another method would be to drill the hole in the plug, but don't go through. Then epoxy the sensor the the inside of the plug. The plug will not be compromised, and the temperature of the plug should be the same temp of the fluid.
 
Curious as to why?

Using wifi to display engine data at the helm as the only source of information is foolish. Wifi for supplemental information elsewhere is fine. I don't think I really need to explain my logic and reasoning for this.
 
I was thinking an interference fit would be ok. One where you under cut the opening a tad. Then you cool down the sensor and heat up the plug until they fit. Then you slip it in and let things stabilize. But then you have to ensure the expansion coefficients for each metal are close enough to ensure they stay stuck. That could also be applicable in this case tho.
 
Using wifi to display engine data at the helm as the only source of information is foolish. Wifi for supplemental information elsewhere is fine. I don't think I really need to explain my logic and reasoning for this.

Actually, if you don't mind I would like for you to explain. Maybe you know something or have a viewpoint I don't? Personally I kinda see wifi as more reliable than a wired connection in this instance. There are no long runs of small conductor wires to get rubbed, cut, vibrated, corroded...etc. Wifi is also TONS faster than the other network protocols. For example I can run video over the wifi network, not so much over nmea. On the garmin, if I wanted engine data and video I'd have to run the NMEA 2k cable and also a video cable for each camera. Also, tech longevity... Wifi is not going anywhere, I'm still pulling out nmea 0183 network stuff and it probably won't be long before nmea 2k is phased out. The changing of marine network protocols is a great way for the mfg's to get everyone to buy new electronics!

For example, if you look at speed alone

nmea 0183 4.8 kb/s

nmea 2000 250 kb/s

wifi 20,000 kb/s

wifi N 300,000 kb/s


Maybe reliability is more your concern? I know it is one of my BIG concerns.

Personally, with an add-on system like this, I don't think I'd rely soley on ANY electronic data as my ONLY source of engine data at the helm. This is why I'll be leaving all analog gauges in tact and having the electronic devices lay over them. They will be easy to remove or hinge away to reveal the analog gauges. I REALLY like the idea of having the redundant system of analog AND digital. This will also allow me to easily remove the digital displays when not in use (at the dock).

Maybe you are confusing wifi reliability with internet reliability? Wi-fi is nothing more than a local area networking technology, just like NMEA (which relies on CAN network - Controller Area Network). They are both networks, both are reliable in a well maintained system.
 
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My serviceability goes to replacing components that are standard not having to make new ones from parts.

I work on many systems and if the parts were not identifiable, easily sourced and readily available nothing would be fixed quickly.

If I need to change a temp sensor on a victron inverter I order the part and I get a plug and play replacement. Time is money and people hate being charged the hourly rate for someone to search the internet for parts.
 
I was thinking an interference fit would be ok. One where you under cut the opening a tad. Then you cool down the sensor and heat up the plug until they fit. Then you slip it in and let things stabilize. But then you have to ensure the expansion coefficients for each metal are close enough to ensure they stay stuck. That could also be applicable in this case tho.

The epoxy I used has a tensile strength of about 4000 psi and a heat range of about 550 degrees F.

I decided upon using epoxy after inspecting several types of temp sensors at Napa, some used what looked like epoxy and others looked to be brazed/silver soldered. In my case the temp sensors were already installed in the stainless probe and I was afraid that soldering/brazing would damage the sensor.

I guess in a perfect world the probe would be soldered/brazed into the fitting, then the temp sensor installed in the probe.

But upon inspection after all my epoxy cured up, I really feel like you would need a hammer and/or drill to get the probe out. I have a VERY high confidence level in them staying together, pretty much forever.

The idea of stopping the hole short was not a good solution imo. The probe needs to be in direct contact with the fluid being measured or else you are going to have some lag time on the temp reading b/c the fluid would have to heat up the metal in the plug before reaching the probe. Maybe some lag would be acceptable, but in an overheat situation where things escalate quickly, I really feel like every second counts.
 
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My serviceability goes to replacing components that are standard not having to make new ones from parts.

I work on many systems and if the parts were not identifiable, easily sourced and readily available nothing would be fixed quickly.

If I need to change a temp sensor on a victron inverter I order the part and I get a plug and play replacement. Time is money and people hate being charged the hourly rate for someone to search the internet for parts.

Yeah, I feel you 100% on this. If I do end up going the commercial route with this the sensors would absolutely be readily available in MANY configurations (thread and plug sizes). You can also hook directly to the existing sensors on the engine. I chose to go all digital with the sensors (where possible), mainly to give a completely redundant system of analog vs. digital.

Everything you are seeing here is prototype stages, all components are readily available, affordable and will be easily produced via small production runs should this go commercial.
 
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Yeah, I feel you 100% on this. If I do end up going the commercial route with this the sensors would absolutely be readily available in MANY configurations (thread and plug sizes). You can also hook directly to the existing sensors on the engine. I chose to go all digital with the sensors (where possible), mainly to give a completely redundant system of analog vs. digital.

Everything you are seeing here is prototype stages, all components are readily available, affordable and will be easily produced via small production runs should this go commercial.

And of course you need a standard plug system that will provide the power and data to devices and not allow a wrong hookup to screw things up.
 
And of course you need a standard plug system that will provide the power and data to devices and not allow a wrong hookup to screw things up.

System consists of a central 'brain', about the size of a stereo amp. On my boat it's located in the cabinet behind the salon TV, but it could be located anywhere on the boat.

There are sub-junction boxes that can be placed anywhere convenient. These junctions have high quality terminal strips to attach sensors. I have 2 junctions located forward of the engines (one for egt and one for temps/pressures...etc) and will likely place one aft of the engines near the electrical panel for those sensors. From the junction boxes a standard Cat-6 cable takes data from the junctions to the cpu brain. You can buy pre-fab cat-6 cables, or make your own cut to length. The small size of a headless cat-6 makes the cables a breeze to pull.

HDMI cable connects the brain to the TV or other monitor, this allows you to use a keyboard/mouse to access the system core.

Keyboard/mouse/trackpad is used via wireless usb mouse/keyboard/trackpad

Pretty much everything else is handled over wifi and will be on touchscreen displays.

My goal with cabling was to use standard, widely available cables, such as cat-6. This way you can buy your cables at walmart/home depot rather than west marine or have to order them. There are also weather proof cat-6 cable ends. I will be using those for the ends of my cables, but a standard cable would work in a pinch, but may not be the best solution in a bilge/humid/wet area.

Of course if you want to connect nmea you will need to purchase a standard nmea cable and junction into your backbone.

Power to the brain can be supplied via 110v AC or 5-48v DC. I've toyed with the idea of an automatic power switch to use ac if available and fall back to dc if ac is not available without interrupting operation.
 
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Micro c is a bitch to run in tight places but seals well. Simrad moved over to it so the old simnet cables are you g away. They were easier to pull as they had a smaller head.

Nmea, J1939 and other can systems use 2 power and 2 data wires. Cat 6 is not as stable or weatherproof even with the expense of weatherized connections. It also can't pass as much power over the buss.

I use a ton of marine cat 5e cable (Garmin) for work on boats and find it's ok. It's easy to terminate and flexible.
 
I use a ton of marine cat 5e cable (Garmin) for work on boats and find it's ok. It's easy to terminate and flexible.

Why would the marine cat 5e better than marine cat6? My main reasons going with the cat 6 was b/c of the heavier gauge wire (23awg vs 24 on cat 5).
 
Garmin Cat5e is very readily available.

It's also more than capable of handling the short runs on boats.

Cat6 cable has additional twist and can cause delay between channels in non it use.

I use the Garmin Cat5e cable for all the Garmin network devices on the Marine Network so I only have to buy one type of cable and its Associated connectors. That way I can't get it wrong
 
Interesting project.

How would you compare this solution to that offered by Chetco?
 

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