Digital Gauges

[Photolomy]

I finally got around to installing an analog-to-digital solution for my engine gauges. I am not doing away with the analog versions, and I have been replacing the broken ones with Stewart Warner but it is a pain because you have to make sure you get dual station senders, etc. Anyways, the digital solution doesn't care about all that and it not only handles all of the gauges, but also the bilge pumps and my alarms (at the helm). I still have a couple inputs left that I might use for fuel levels, if I ever get fuel level senders for my tanks. I might instead use it for my rudder. I would love to know where it is pointing when I start out.

I was looking at several solutions, but a couple (Actisense and Alba-Combi) were foreign, so they were kind of at the bottom of the list. Two rose to the top of the list, Noland and Chetco, because of the number of inputs supported. And of course, there is Maretron, but their solutions require additional pieces and start running up the cost considerably. I should note that I really wanted to do my own Arduino solution but the NMEA-2000 piece would have taken too much time to research. The analog to digital part is pretty straightforward, but there just wasn't enough open source stuff available for the NMEA-2000 part, and it would have cost me considerably more in time than to just buy something already made.

So in the end it was between Noland and Chetco. I think Chetco is more advanced but it turns out in a bizarre coincidence, Noland's office is a couple blocks from my boat. I have been looking at these things for months and only recently noticed that the Noland address was in the same city, and when I googled it, it was within walking distance. Also, I already have a PC on board that I can access remotely and control the lights etc. And the Noland box interfaces with that PC easily.

I was originally going to get a pair of RS-11's, which is their more popular model, but changed to the MD33 model for the following reasons...

1. It has RPM and 5 inputs for each engine, while each RS-11 had RPM and 6 inputs, but the MD33 also has 5 on/off sensors for each engine as well, which covers all of my bilge pumps and engine alarms, plus a couple more for whatever.

2. The MD-33 has a serial interface built in that not only sends the sensor data it collects, plus also most of the common NMEA-2000 traffic and NMEA-0183 traffic. This saves me from having to add an additional NMEA-2000 interface.

The MD33 also comes with a PC app to display the gauges, but I am actually going to integrate the data into my existing applications, but it is handy to use the supplied app for testing and calibration.

I'll post pictures over the next couple of days of the installation. The nice thing about the MD33 (and I assume this is also true for the Chetco) is that it can operate with or without the analog gauges. This means that you can wire it directly into your helm where everything is close by. I mounted mine on the back of the front panel, right below the Newmar 12V converters. Creating a wire harness wasn't too bad, but it was a bit of challenge getting 26 wires into the small opening on the MD-33. After that, the only real challenge was working in the confines of the helm amongst the other cables. Nonetheless, if you are prepared, it can be done in a weekend.

 

[JD5652]

Sounds like a great project.... and I need to do the same.... very interested in how yours came out!

 

[Photolomy]

Here is a picture of the device itself ...



Across the top are the analog and digital inputs for each side (PORT and STBD). The A5 analog input on each side has a range of 0 to 40 volts, which makes it perfect for the volt meter. The remaining analog inputs have a range of 0 to 30 volts which works for the rest of the gauges since they operate on 12 volts. On the bottom are the RPM inputs and the NMEA-0183 in and out if you have some older stuff. On the left is the NMEA-2000 connector and on the right is the USB (top) and access for all the wires to the gauges (bottom).

To build a wiring harness to attach the MD33 to the gauges etc, I chose some 20 gauge 8-wire color coded cable from West Marine. I didn't need a lot, or I would have sourced it somewhere else.

https://www.westmarine.com/buy/ancor--20-8-round-signal-cable-by-the-foot--541748?recordNum=7

This allowed me to have 3 bundles, one for each engine, and one for the alarms/bilge pumps.



And finally, here it is with all of those wires inserted through that too-small hole and connected. I used the same colors for each side (PORT and STBD) to make it easier when connecting to the gauges. You definitely want to do all of this on a table first, before installing in the console. And make sure you mark which cable is which. You can also see the red/black power cables. There are a total of 26 wires running into the box. 10 analog, 10 on/off, 4 RPM and 2 power.

 

[Photolomy]

Here are a couple pictures of the helm prior to the install. This first picture is of the lower section...



The black boxes are the Newmar 32v to 12v converters. The two smaller (3 amp) converters are for the gauges, port and starboard. There are inline fuses above each converter that are a bear to open. If the gauges on a whole side (except the voltage gauge) are not working, then go to the fuse first. Keep in mind that the fly bridge is separate and has its own Newmar converters, just like the lower station. Just something to keep in mind when troubleshooting gauges.

Above the Newmars is a fuse block for the gauges and parallel switch. To the right of that is the alarm buzzer and to the right of that is the back side of the console alarm unit. I cleaned out a lot of wires from all the older electronics (Loran, Depth Sounder, etc.).

The MD33 will mount below the Newmars and it will be powered by the 12v generator battery which also powers my radios and chart plotters. The MD33 only draws 0.1 amp, so you could easily power it from one of the Newmars, but the Newmars are only live when the ignition key is on, which is how they last 40 years. But I want the MD33 on all of the time because it will also monitor bilge pump activity and the high water alarm. Thus is why I connected it to the generator battery. Before I did this, I used a multimeter to make sure that the ground of the generator battery was common to the gauge grounds (main batteries) and that appears to be the case. The MD33 has only one ground and in order to measure the gauges that ground has to be in common with them. In any event, it was.

This is the picture of the upper part showing the gauges...



The MD33 will handle all of these. Keep in mind that only the A5 input will handle 40 volts, so those must be connected to the voltage gauges. A1 through A4 are connected to the other gauges. I only needed A1 through A3 for Temp, Oil and Drive Pressure. There are two additional connections for the tachometers. I actually only needed one wire for each tachometer. The inputs connect to where the senders connect to the gauges. You can see where that is because that will be the terminal with only one wire connected to the gauge. The other terminals have multiple wires connected because the ignition and ground wires are daisy chained from gauges to gauge. Make sure the key is off when working back here because the space is cramped and you will be blowing fuses left and right, or blowing gauges. All of the gauges operate on 12v, except the voltage gauge which is 32v.

Four on/off inputs connect to the bilge pump indicators at the right. For those I use resistors to bring the voltage down. Likewise, I will use four on/off inputs with the alarms, though I am still working out the method.

And of course, the NMEA-2000 will connect to the Garmin.

 

[davidwigler]

So it works? I have the MD33 I bought years ago and never could get it working. How much would you want for a working vacation in Knoxville?

 

[Photolomy]

Here is a shot after the install. I still have some cable management to perform.



I have been calibrating and so far that is going ok, but with a variety of old senders, I can see how this step can be troublesome. The tachs are pretty easy, as is the voltage gauges. I tested the unit with a spare temp sender and water heated to various temps and was able to dial it in pretty well. In fact, it was tracking a cooking thermometer within a degree or two. For the pressure gauges I am taking an educated guess from my working gauges. I'll have to install mechanical gauges to get more accurate readings to calibrate to. I'll post some screen shots of the app and the Garmin while the engine is running as soon as I dial it in more. I also have a bad drive pressure sender, or a loose wire.

Btw, what are common pressures for the oil and drive at idle? I am getting around 40 and 150 psi.

 

[davidwigler]

Oil pressure starts at 40 plus cold and warms to around 20 psi at idle.

My gear oil pressure reads around 100 to 120 psi, lower than most.

Mechanical gauges in the ER.

 

[Photolomy]

So it works? I have the MD33 I bought years ago and never could get it working. How much would you want for a working vacation in Knoxville? 

Yeah, it is working. The box and the firmware seem very solid. It has been on continuously for a couple of days, even while I have been connecting and reconnecting gauges. The app crashed a few times though, but I figured out what it doesn't like, such as cancelling a config window or trying to connect without the USB plug in. What has taken some time though is realizing that while you can configure the app gauges to be what you want them to be, you are limited on the NMEA messages that can be associated with the inputs. For example, you can use engine temp, but it has to be with A2, while oil pressure can be used with any input. Thus, the app was setup and working but the Garmin gauges were either doing nothing, or showing gibberish compared to the app gauges. I finally figured that out and now the app and the Garmin are saying the same thing. Now I am looking at the condition of a couple of my senders, which is one of the purposes for getting this. Once you do set it up the voltages it reads are pretty accurate, within 1% at least, and I can watch a remote screen in the ER while I fiddle with a sender.

I hope maybe what I post here might help you along. How far did you get when you tried to hook it up? There are some pitfalls like what I mentioned above. If you start off just wiring gauges in any order (like I did) you might not get the expected results on your multifunction displays. I had to change how I wired them a couple times before I straightened it out. Fortunately, I did this on the port side first, so I knew what I was doing when I did the starboard side.

 

[Photolomy]

Some shots of the Garmin with everything hooked up. In some shots the engines are running, some not. I didn't run the engines very long, so they didn't warm up. I have a monitor attached to the Garmin on the side, showing the same screen. The Garmin has an extensive number of layouts.







Comments thus far...

The unit seems very reliable from an up-time perspective. It is wired directly to the fuse box so it has been on all the time for the last couple days. I will add a switch so that I can turn it off when I need to, or to reset it if that ever happens. Likewise, the serial port drivers have been reliable thus far, and I am pretty sure that it will function fine connected to my ship server, logging and reporting (via email) any bilge or alarm activity.

Regarding the engine monitoring, it depends on the condition of your senders...

RPM good (I checked with a laser tachometer). There is some jitter at low RPMs but that goes away at higher RPMs. Similar to the analog gauges I suppose.

Water temp seems fine, the senders have a decent range.

Oil pressure, one is "ok" but the other has a narrow range which affects accuracy and jitter.

Drive pressure, again, one is "ok" but the other has a narrow range.

Regardless of the sender issues, I was able to calibrate to the narrow ranges and get readings, however, the narrower the range the less the accuracy and the more jitter in the readings. The Garmin does a good job of smoothing the data, while the app that comes with the unit does not smooth at all I think. I generally use the app for calibrating though and the application I write will smooth.

Next step is to replace some senders and add mechanical gauges in the ER as a reference.

 

[Photolomy]

What is a good (and easy to install) sender for the fuel tanks? Are the ultrasonic senders any good?

 

[MadHatter53]

Thanks bud now I gotta add this to my list of updates.

 

[davidwigler]

Yeah, it is working. The box and the firmware seem very solid. It has been on continuously for a couple of days, even while I have been connecting and reconnecting gauges. The app crashed a few times though, but I figured out what it doesn't like, such as cancelling a config window or trying to connect without the USB plug in. What has taken some time though is realizing that while you can configure the app gauges to be what you want them to be, you are limited on the NMEA messages that can be associated with the inputs. For example, you can use engine temp, but it has to be with A2, while oil pressure can be used with any input. Thus, the app was setup and working but the Garmin gauges were either doing nothing, or showing gibberish compared to the app gauges. I finally figured that out and now the app and the Garmin are saying the same thing. Now I am looking at the condition of a couple of my senders, which is one of the purposes for getting this. Once you do set it up the voltages it reads are pretty accurate, within 1% at least, and I can watch a remote screen in the ER while I fiddle with a sender.

I hope maybe what I post here might help you along. How far did you get when you tried to hook it up? There are some pitfalls like what I mentioned above. If you start off just wiring gauges in any order (like I did) you might not get the expected results on your multifunction displays. I had to change how I wired them a couple times before I straightened it out. Fortunately, I did this on the port side first, so I knew what I was doing when I did the starboard side.

I hooked up the starboard side. As I recall the tach worked but I never was able to calibrate the gauges. I bought all new senders and ran new wires directly to the senders. I spent over a week in total frustration and gave up. I’d love to get it working but it’s over my head.

 

[JCG-PR]

Hey Photolomy, could you let me know what operating system you're running in the PC you are using to program your MD33? I've had trouble with my Windows 10 laptop quickly loosing connection with the Noland, making it extremely difficult to program. A friend got my rpm, oil and drive pressures pretty spot on, but my temp gages are not even close. I tried to get them better, but got frustrated with the connection loss. Any advice?

Thanks!
Julian

 

[Photolomy]

I used a cheap HP netbook running Windows 10 and a MacBook running a Windows 10 VM and neither had connectivity issues. I believe one was Win 10 Pro and the other Win 10 Home, so that wasn't an issue. In fact, I am remoted into the netbook (on the boat) from my MacBook (at home) and the netbook is connecting fine.

There are two ways to calibrate. One way is from the CPort screen by opening the config window for the gauge you are calibrating (temp for example). I have noticed that if you cancel out of that config window it will crash. I always hit "Ok" instead, even if I didn't change anything.

However, configuring in the CPort screen only calibrates the CPort software. To calibrate the MD33 itself, so that it sends actual temp to the NMEA-2000 network you must use the calibration software. That hasn't crashed on me. Well, unless I attempt to connect without first setting the COM port.

But, before you can use the calibration utility, you need to know what pairs of values to use, and to do that you use the CPort software, and don't cancel out of the config windows.

What I do is first set the calibration to 0 / 0 and 20 / 20. This basically means that the actual voltage will be shown on the gauge. For a temp gauge cold you might see something like 12.3 volts. And for a temp gauge hot, say 160 degrees, you might see something like 8.2 volts. So, your calbration points are 12.3 / 80 and 8.2 / 160 (I am assuming that the water when cool is 80 degrees). That should then get you close.

You can set those in the CPort software, and also set them in the calibration utility to calibrate the NMEA messages as well.

Let me know if this helps. If it isn't the config / cancel glitch, then maybe reinstalling the USB driver from the Noland flash drive might help. Early USB/Serial drivers were notorious for crashing but nowadays they are pretty stable, and this has been pretty stable.

 

[Photolomy]

Here is a connection diagram that may help someone in the future...


As you can see, you can hook up quite a bit of stuff. The nice thing is that all of those connections, except the rudder and AC pump, can be made all within the helm console. No need to run any long wires. For the bilge pumps, I connected to the bilge pump lights using resistors (voltage divider) to bring the voltage down from 32 volts. Likewise, the same concept for the alarms, using the alarm lights. I already have a connection to the 12 volt (generator) battery, as that powers my radios. And the AC shore power can be connected using a cheap 12 volt power supply or even a spare USB charger. The MD33 includes two op-amps that could be used to sense the current in the AC lines. I will use one of those to do the AC pump.

 

[Photolomy]

Here is more detail on how to sense 32 volts when you are limited to 20 volts...



In this example, I want to sense when 32v is going to the bilge light on my helm console (even if the light is burnt out, this still works). I add the two resistors shown from the input to the light to a ground and connect the sensor between them. The sensor will get 100 / (100 + 200) = 1/3 the input voltage. You want the resistors to be large so that no real current flows through them (otherwise you would be shorting out the light). In this case there would only be 32 / 300k = 0.1 milliamps. Also note that there is no current at all, unless the bilge pump is on.

 

[scottinsydney]

Could the Noland be connected to Floscan senders? Two pulse and one ground wires for each engine.

(I bought the Floscan NMEA2000 system. Floscan went out of business the next day and there seems to be a wiring diagram error.)

 

[Photolomy]

Could the Noland be connected to Floscan senders? Two pulse and one ground wires for each engine.

(I bought the Floscan NMEA2000 system. Floscan went out of business the next day and there seems to be a wiring diagram error.)

I think they would certainly connect and report pulses per minute, but they wouldn't do the math. You would actually need two of the RS11's (cheaper than one MD33) because they each have two RPM inputs. One RS11 for each engine. But, as I said, the software will not subtract the return rate from the feed rate and convert that all to GPH. You could write an app that does that calculation on a PC though.

You can call Noland and ask. They are pretty good about responding.

https://www.nolandeng.com

What would be cool if Noland allowed you to add your own code to the box itself. The calculations for GPH are pretty simple and then you could output the NMEA messages for fuel flow.

 

[Photolomy]

Also, what isn't wiring correctly with the FloScan stuff?

 

[scottinsydney]

I sent the old Floscan gauges for repair and also purchased a new sender and Flonet NMEA2000 box. The startboard NMEA gauge was modified to output to the Flonet box. Both gauges talk to each other and also to the Flonet.

The gauges work fine and are pretty accurate. Assuming I have wired the Flonet as per Floscan instructions, then the Flownet top line reads 80 litres per hour when the actual fuel consumption on the gauges is about 32 litres per hour for both engines.

So today I have bought an NMEA2000 wifi transmitter from www.yachtd.com and will see if the fuel flow readings on my iphone work properly. Wifi will arrive Friday or Monday and will post results in new topic. Yachtd have a really interesting range of NMEA products

The Noland review is excellent, thank you Prometheus.