Maretron NMEA 2000 Fuel Monitor

[millennium]

Hello All:

I do several long, offshore trips a year and would like to know exactly my fuel burn rate and remaining fuel. I have been considering the Maretron fuel monitoring system for my twin diesel Mainship 390.

For a twin, I would need two displays, two fuel monitors, four flow sensors, two level indicators, many various connectors and cables. All together about $4,000.

I have compared this system to Floscan, the Maretron appears easier to install and have better accuracy.

Does anyone have experience with Maretron, installation and operation?

Thanks

 

[Pau Hana]

I've played with the system, and the only hiccup I found is that you'll need the DSM-250 to set the initial programming. Once it's set, you can have the output data display on most newer generation MFDs via NMEA 2000.

The Maretron sensors don't need the pulse dampeners that Floscan do, so the physical installation is much more compact. Overall, I was very impressed with the system.

 

[FF]

>the Maretron appears easier to install and have better accuracy.<

We have a flowscan , and the accuracy is dialed in as the boat is used.

The unit reads you used 157 gal, and the dock pump shows 170.

You adjust the flowscan to read 170 and start again.

After a few fills the accuracy frequently gets to within a gallon or two.

Good enough to know when to switch tanks , and when to reach for the oars.

 

[BobH]

Just recently installed a twin engine Floscan system. I was surprised by the size of the pulsation dampers, that did require some planning for the mounting. I do like the MPG readout.

Bob

 

[HenryD]

I would not think you would need two displays.
Depending on the display, you should be able to show two instancies and be able to go back an forth.
I have installed the Maretron backbone, 4 tank sensors (two were gifted to me when I ran two tanks dry), PB200 weather sensor, analog to NMEA2000 engine monitors, etc. If you have a PC onboard, it can be used as the display with the N2Kview software and a USB100.
The more you install, the easier it becomes, as you only need to T the backbone.
I totally rely on the NMEA tach readings - so much better than the analog guages. I do have it all tied into my Coastal Explorer so I get the NMEA info as data also.

 

[twistedtree]

I've got a bunch of the Maretron equipment and really like it. It's high quality, the support is really good, and they continually make improvements to the software/firmware.

I have a couple of tank level monitors, but have not used it for fuel flow measurements. I have a DSM250 display and believe you can set it up to show both engines on one screen - no need to switch between screens.

As for displaying fuel consumption rate on something like an MFD, I'd check with Maretron on that before assuming it will work. As you probably know there are two flow meters for a diesel; one for the inlet and one for the return. Consumed fuel is the difference between the two. I just don't know where the calculation is done and whether the result is on the N2K bus which is what would be needed for some other device to display it. But they probably have it figured out. All their installation manuals are available on line and they are among the best I've found for electronic equipment. They are also very helpful on the phone. Your success is there success, and they understand that.

 

[Pau Hana]

As for displaying fuel consumption rate on something like an MFD, I'd check with Maretron on that before assuming it will work. As you probably know there are two flow meters for a diesel; one for the inlet and one for the return. Consumed fuel is the difference between the two. I just don't know where the calculation is done and whether the result is on the N2K bus which is what would be needed for some other device to display it. But they probably have it figured out. All their installation manuals are available on line and they are among the best I've found for electronic equipment. They are also very helpful on the phone. Your success is there success, and they understand that.

The fuel sensors (feed and return) are connected to the FFM100 unit; the FFM 100 ties into the NMEA2k backbone. Most late model MFDs have a menu selection for fuel consumption data built in. Use the DSM250 to set calibration, and you should be good.

 

[HenryD]

You can use the "virtual DSM250" in N2KAnalyzer to do the calibration also if you have a PC connected

 

[millennium]

Thanks all for your good advice and ideas. I am almost over the sticker shock, my first boat cost less then the Maretron components.

I like the idea of future adding on of other things, engine monitoring. weather, etc.

Like many here I am a retired pilot, I want to know exactly what is happening with fuel. It may not be as important cruising down the ICW as it was on an airbus, but still nice to know.

 

[twistedtree]

The fuel sensors (feed and return) are connected to the FFM100 unit; the FFM 100 ties into the NMEA2k backbone. Most late model MFDs have a menu selection for fuel consumption data built in. Use the DSM250 to set calibration, and you should be good.

That makes sense, thanks. I should know that since I'm installing this exact setup in my new boat, but I just haven't gotten that far yet.

 

[twistedtree]

For a twin, I would need two displays, two fuel monitors, four flow sensors, two level indicators, many various connectors and cables. All together about $4,000.

Just to reiterate, I think only one display, presuming a DSM250, is required. You can display data for both engines on it, either on different screens or one a single screen. You may prefer two complete displays, but if you are trying to shave the cost, that's one way to do it.

 

[millennium]

Thanks Twistedtree

Looking at available panel space more then anything. I do have space for two of the smaller dsm150s but not a single 250.

I'm not ready to loose the round gauges yet, maybe someday if I get the engine interface, which Maretron does have for my Yanmars.

 

[timjet]

I would love to have fuel flow indication but can't justify the cost. With some experience though, I have gotten pretty good at estimating fuel burn. I can usually get within 5 gallons when I refuel.

 

[twistedtree]

Thanks Twistedtree

Looking at available panel space more then anything. I do have space for two of the smaller dsm150s but not a single 250.

I'm not ready to loose the round gauges yet, maybe someday if I get the engine interface, which Maretron does have for my Yanmars.

Will the Yanmar's report fuel burn over their interface? Electronically controlled engines typically do, and it's more accurate than adding flow gauges. It might be worth looking into.

 

[millennium]

I have the older mechanical motors. No fuel burn available there.

Putting the order together, a bit confusing the way Maretron labels their connectors. Mini, micro, mid. Ending up about 3,700. for twin engine fuel flow, ultrasonic tank levels, two small displays, gps for mpg.

 

[twistedtree]

I have the older mechanical motors. No fuel burn available there.

Putting the order together, a bit confusing the way Maretron labels their connectors. Mini, micro, mid. Ending up about 3,700. for twin engine fuel flow, ultrasonic tank levels, two small displays, gps for mpg.

Too bad on the engines. The system sounds good. Is there no easy way to connect your chart plotter to N2K? That would get you your existing GPS. You might be able to get there from your auto pilot too. Simrad's Simnet is N2K with different wires and connectors. Just replace the connector with an N2K connector and they hook right up. But your gear might be too old to do any of this. It all depends on it's vintage.

One tip on the fuel level sensors, having gone through many iterations of different sender approaches on my Grand Banks. Be certain there is a clean, unobstructed view from the sender port down to the bottom of the tank. If there are nearby baffles, you can use Maretron's focus tube to restrict where the sounder "looks". Also, the bottom of the tank needs to be flat and smooth or it can confuse the sounder when you reach empty. One work around is just to not draw you tanks down that low, but it's something to be aware of. My tanks have a V shaped bottom, and the sender fitting is offset to the side so I failed on all counts.

They also have a sensor that works in conjunction with traditional resistive fuel senders. It might be more cost effective to tap into them. Plus, you would get the bonus of having both systems in place for redundancy and cross-checking.

And last but not least, they offer tank level sensing using pressure gauges. These are typically fitted at an existing port at the bottom of the tank and measure the head pressure of the fuel above them. This is what I ended up doing. If you get serious about this approach, let me know as there are some critical tips that I figured out the hard way.

Re Micro, Mini, etc, it is confusing when you first get started. Have you found Maretron's wiring guide? It's very helpful. In short, micro is the smallest and is the fitting used on all the devices. For a medium sized network you can build everything out of the micro devices and is simplifies a lot of things. My GB is built this way and runs from mast to stern with about 20 devices on it. Works great, but I highly recommend using Maretron's N2KBuilder program to model your network. It's free software and will verify that you are building something that is electrically correct. Little things like where you locate the power feed can make a big difference as the network gets longer and has more devices.

But you've probably already figured all this out.......

 

[CaptTom]

So, assuming I will at some point have a NMEA 2000 network, and since my MFD already displays NMEA 2000 data, I would need the following Meretron components to see real-time fuel burn rates on my twin diesels:

2 x FFM100 fuel flow monitors ($800)
4 x M1RSP-2R-E8 fuel flow sensors ($1600)
Total: $2400.

Is this right? Or is there more?

It still seems like a lot of money for a few sensors and some processing logic. Even the overpriced iPad, with much more processing power, a bunch of different sensors, PLUS memory, touch screen, wifi network, etc. is a fraction of this price.

 

[twistedtree]

So, assuming I will at some point have a NMEA 2000 network, and since my MFD already displays NMEA 2000 data, I would need the following Meretron components to see real-time fuel burn rates on my twin diesels:

2 x FFM100 fuel flow monitors ($800)
4 x M1RSP-2R-E8 fuel flow sensors ($1600)
Total: $2400.

Is this right? Or is there more?

It still seems like a lot of money for a few sensors and some processing logic. Even the overpriced iPad, with much more processing power, a bunch of different sensors, PLUS memory, touch screen, wifi network, etc. is a fraction of this price.

I think that's right, but you will also need to get it all configured initially. That can be done with DSM250 or DSM150 display, or their N2KAnalyze software using a USB100 interface. Perhaps you can borrow what you need from an installer or friend. That said, I have found the N2KAnalyze program to be very useful and worth the cost of the USB100 interface.

I just took a look at Floscan and they have an N2K product as well. It's real hard ot tell what sensors come in which packages, but it looks like it costs around $1900 per engine, so amazingly Maretron is cheaper.

 

[kulas44]

My trawler has two 25 gallon "day" tanks that are filled by walbro pumps from the main or bulk tanks. When the tank gets low the switch turns on the pump, at about 10 gallons. I have a cycle counter that counts every time the pump comes on. Gallons per hour are easy to figure, and right on the money. MPG is what I look at mostly. So if I go 100 miles and the pump cycles 10 times I got 1 MPG. Also easy to figure, and ultimately reliable. I usually get better milage than that but you get the idea. I can also turn the pump on and circulate fuel endlessly, the overflow goes back to the bulk tanks. Or I can turn on the gear rotor pump and circulate any tank thru the bulk filter system. Or feed the engines from any tank (of 6) onboard. Both engines have there own fuel supply. The old saw that "a fuel problem will get both engines" does not apply. But I'm kinda paranoid about this stuff. Then again, you dont even want to know what I run for fuel. Detroits will burn anything if its clean.

 

[millennium]

Twisted: I have Raymarine classic MFDs. Very limited fuel info can be displayed on then, hence the two Maretron displays. I also wanted the stand alone GPS as a backup to the Ray unit. I want the fuel info completely separate from my nav system.

I have been using their n2k builder, which took some learning in it self.

Capt Tom. The various connectors and cabling will add a few hundred dollars to the bill.

From what I've seen the Maretron fuel flow components do not need the calibration that Floscan requires.

 

[twistedtree]

From what I've seen the Maretron fuel flow components do not need the calibration that Floscan requires.

But there is still some minimal configuration required, right? I guess what I'm saying is that I don't think you can get away without some other Maretron product to do the initial setup. If you have some other way to display the data once set up then you could borrow the stuff to do the setup and then remove it. But I think you have to have it initially to get going.

 

[AKFish]

I'm pretty sure that you can use the free software, N2KAnalyzer. I'll let you know in a week as that is my plan to install ffm100 and I don't have a Maretron display. I am using a N2K bus and furuno MFD. I used the software in the past to configure a Maretron SSC device without issue. Good luck.

 

[CaptTom]

I'm pretty sure that you can use the free software, N2KAnalyzer. I'll let you know in a week as that is my plan to install ffm100 and I don't have a Maretron display. I am using a N2K bus and furuno MFD. I used the software in the past to configure a Maretron SSC device without issue. Good luck.

Thanks! Looking forward to hearing how the install went for you. This is getting close to the top of my "to buy" list.

 

[FF]

>From what I've seen the Maretron fuel flow components do not need the calibration that Floscan requires.<

Perhaps ,,but the flowscan calibration is a snap to do , a couple of fillups .

Always fun to see how well the predicted fill gal match the actual .

For folks with a day tank with a sight glass (or dip stick in smooth water) a log will do almost as well, at no cost.

 

[sunchaser]

For folks with a day tank with a sight glass (or dip stick in smooth water) a log will do almost as well, at no cost.

Ahh, to own a Nordhavn. My DeFever tanks are all calibrated with sight tubes but it takes a few hours of operating to get +/- 5%.

BTW, today's new engines have very accurate fuel flow algorithms/devices as part of the on engine controls. These readouts can be added to a Maretron display or read directly off the instrument cluster.

 

[BeagleBoy]

I purchased my first larger boat (89 48ft Nova) in June last year. I had completed many hours of research on forums about how much fuel a cruiser of this size would use prior to buying. Definitive answers are not really available as there are simply too many variables. The very first expenditure after settlement day was on the Maretron fuel flow monitor system. With twin 3208AT 375HP CAT's and 20 tonnes of boat I thought the system would be the best investment for us over the life of the boat. People can tell you how many nautical miles they have done this season and how much fuel they used but without a fuel flow monitor you cannot tell how much you are using in real time. By having this knowledge in real time you can save a LOT of money.
I purchased 2 x FFM100's, 4 x M1RSP-2R-E8 fuel flow sensors, 1 x GPS200, 1 x DSM150, and a NMEA2000 starter kit plus a few extra cables. You must have the DSM150, DSM250 or the Nk2 Software and the PC connection to configure the devices. You must have an NMEA2000 GPS to give you the Nautical Miles per litre or gallon readings. Otherwise you can only have litres or gallons per hour.
I installed myself - if you have never done any of this kind of thing before, you do have to read the documentation (and again, and again.....) relating to what you want to do and then fill in the blanks yourself.
You can display a range of things on the screens. I have attached a couple of examples. You will note from the 2 images that depending on something as simple as a 12 knot wind or current it can affect the speed but you can still maintain a desired fuel burn. Without this kind of system you will think that your best fuel burn is at xknots and sit on that everywhere you go. What I have found is that on any given day my fuel burn at a desired speed can vary by as much as 100%!
We now drive the boat only by the fuel flow monitors and our desired fuel burn - this is a combined 2ltrs per nautical mile. Some days we are doing 12knts in a tidal current and tail wind - other days it can be as low as 6knts.
The only modification I had to make to the equipment out of the box was lengthen the cables for the flow sensors. the FFM100's should not be mounted in the engine room as they should not be in temperatures of greater than 50 deg Celsius. They only come with 1mtr tails on them out of the box.
I would highly recommend purchasing the system - you can add to it over time and take it with you to the next boat (unless you can afford a new boat which will most likely have them!)
Sorry but I do not have experience in outputting the data to an MFD - I have a Raymarine C120 Classic which does not have NMEA2000 connectivity. (apparently possible via Seatalk 2 but I have not found anyone with specific instructions - if anyone knows I am happy to hear from you )
I hope this is helpful for you.

 

[CaptTom]

Thanks for sharing!

I've already got a Garmin 740s MFD that uses NMEA 2000, and I'm working on putting in a NMEA backbone to connect several other sensors.

From your write-up, it appears all I need to add fuel data are:
• 2 x FFM100's,
• 4 x M1RSP-2R-E8 fuel flow sensors

I'd prefer to configure it using software and a laptop. Is the software included with the FFM100s, or do I have to buy it?

 

[AKFish]

I'd prefer to configure it using software and a laptop. Is the software included with the FFM100s, or do I have to buy it?

As correctly mentioned, you need the USB to N2K gateway device. I have a Maretron one and it will definitely talk with Maretron equipment. I don't know if the Actisense gateway will work with the free N2KAnalyzer software.

 

[CaptTom]

As correctly mentioned, you need the USB to N2K gateway device. I have a Maretron one and it will definitely talk with Maretron equipment. I don't know if the Actisense gateway will work with the free N2KAnalyzer software.

Thanks, looks like I should invest in the Maretron USB100 gateway.

Then again, the NoLand RS11 unit I bought comes with a USB connection, too. I wonder if that will allow me to see "through" it to the N2K bus and the Maretron unit.

 

[twistedtree]

Then again, the NoLand RS11 unit I bought comes with a USB connection, too. I wonder if that will allow me to see "through" it to the N2K bus and the Maretron unit.

It's easy enough to try. Just download the N2KAnalyze software and give it a try.