N200 Network for Dummies?

maxton1

Junior Member
I read @goldenstate's thread on installing his N200 network and, well, yikes. I just want to install a simple network so I can use the dash panel function on my Garmin. The tach is out on my '84 28+ and I'd rather have something I can read from the helm, anyway, rather than having to bend over to look at the gauges. If I could just get RPM, fuel level, engine temp senders to feed my Garmin I'd be happy. Is this a fairly simple/cheap installation? I'm not an idiot, but I'm not a rocket scientist either. Has anybody had experience with this more basic network installation?
 

Baslin

Member III
I haven’t looked into what would be involved in doing that but I would guess that you would have to replace all of your gauges to be able to send data over the CAN network. Along with the gauges having to be replaced, there will have to be some sort of “brain” that would collect the information from the temperature gauges, tach and fuel, and then transfer them onto the CAN network For other control modules to pick up and display.
 

mbp

Ericson 34
Life long computer nerd here. There is no magic bullet, but a little info can help understand the pieces.

A NMEA 2000 (or N2K) network is a wired cabling system that lets everything connected to it send and receive little text messages to all the other connected devices. Your Garmin MFD (which model?) knows how to listen for tachometer messages or engine temp messages and will display the values in the messages if it sees them.

Your fuel and temp senders work by creating some resistance depending on the fuel level or the engine temp. For example, fuel senders often show about 33 ohms for full and 240 ohms for empty. The gauges read that resistance and convert that resistance to dial movement. All analog and old school electronics. To see this info on the Garmin MFD, you need some way to convert electrical resistance to NMEA messages.

There are devices that can convert electrical resistance readings into NMEA 2000 messages. You don’t have to replace your senders or gauges. One such device is the Actisense EMU-1. It costs around $450. It also requires the Actisense NGT-1 (USB version) ($225?) to program the EMU-1 and a PC to do the programming. This is an expensive device and it is also a very generic conversion device. It can be connected to many kinds of engine senders.

The EMU-1 also has dedicated input connectors for connecting a tachometer.

Lastly you need to figure out how to configure the EMU-1. The EMU-1 has 6 gauge inputs, but they are generic inputs. To configure the EMU-1, you use the PC software that comes with the EMU-1 to say what engine sender is connected to each input. For example, you might connect gauge input #1 on the EMU-1 to the fuel sender. You use the PC software to set gauge input #1 to send NMEA 2000 fuel level messages, uand when the input reads 33 ohms broadcast tank full messages, and when it reads 240 ohms broadcast tank empty messages.

You‘ll also need to run NMEA cables between the Garmin and the EMU-1 and there are some details like cable termination that need to be followed.

If you are willing to pay for the Actisense devices, it might be time to talk with your computer nerd friends and see if they are willing to help out with the configuration. They might consider it an interesting challenge.

There are other engine monitoring devices available. The EMU-1 is just one example. But they all involve understanding how to connect your senders to the monitoring device and how to perform the configuration.
 

maxton1

Junior Member
Life long computer nerd here. There is no magic bullet, but a little info can help understand the pieces.

A NMEA 2000 (or N2K) network is a wired cabling system that lets everything connected to it send and receive little text messages to all the other connected devices. Your Garmin MFD (which model?) knows how to listen for tachometer messages or engine temp messages and will display the values in the messages if it sees them.

Your fuel and temp senders work by creating some resistance depending on the fuel level or the engine temp. For example, fuel senders often show about 33 ohms for full and 240 ohms for empty. The gauges read that resistance and convert that resistance to dial movement. All analog and old school electronics. To see this info on the Garmin MFD, you need some way to convert electrical resistance to NMEA messages.

There are devices that can convert electrical resistance readings into NMEA 2000 messages. You don’t have to replace your senders or gauges. One such device is the Actisense EMU-1. It costs around $450. It also requires the Actisense NGT-1 (USB version) ($225?) to program the EMU-1 and a PC to do the programming. This is an expensive device and it is also a very generic conversion device. It can be connected to many kinds of engine senders.

The EMU-1 also has dedicated input connectors for connecting a tachometer.

Lastly you need to figure out how to configure the EMU-1. The EMU-1 has 6 gauge inputs, but they are generic inputs. To configure the EMU-1, you use the PC software that comes with the EMU-1 to say what engine sender is connected to each input. For example, you might connect gauge input #1 on the EMU-1 to the fuel sender. You use the PC software to set gauge input #1 to send NMEA 2000 fuel level messages, uand when the input reads 33 ohms broadcast tank full messages, and when it reads 240 ohms broadcast tank empty messages.

You‘ll also need to run NMEA cables between the Garmin and the EMU-1 and there are some details like cable termination that need to be followed.

If you are willing to pay for the Actisense devices, it might be time to talk with your computer nerd friends and see if they are willing to help out with the configuration. They might consider it an interesting challenge.

There are other engine monitoring devices available. The EMU-1 is just one example. But they all involve understanding how to connect your senders to the monitoring device and how to perform the configuration.

This is great info, thanks! I do have some nerd friends who could help me with this. Would a surface mount tank sender work for the fuel tank? I'm getting something similar for my fresh and black water tanks. I don't have the Garmin in front of me, but I think it's a GPSMAP 750, and I know it has networked dash functions. I would really love to be able to read all the important engine information on it, as I'm not happy with my stock gauges. The tach doesn't work at all and the fuel and temp gauges are suspect at best. Plus I hate having to look down at my feet to see them.
 

1911tex

Sustaining Member
Life long computer nerd here. There is no magic bullet, but a little info can help understand the pieces.

A NMEA 2000 (or N2K) network is a wired cabling system that lets everything connected to it send and receive little text messages to all the other connected devices. Your Garmin MFD (which model?) knows how to listen for tachometer messages or engine temp messages and will display the values in the messages if it sees them.

Your fuel and temp senders work by creating some resistance depending on the fuel level or the engine temp. For example, fuel senders often show about 33 ohms for full and 240 ohms for empty. The gauges read that resistance and convert that resistance to dial movement. All analog and old school electronics. To see this info on the Garmin MFD, you need some way to convert electrical resistance to NMEA messages.

There are devices that can convert electrical resistance readings into NMEA 2000 messages. You don’t have to replace your senders or gauges. One such device is the Actisense EMU-1. It costs around $450. It also requires the Actisense NGT-1 (USB version) ($225?) to program the EMU-1 and a PC to do the programming. This is an expensive device and it is also a very generic conversion device. It can be connected to many kinds of engine senders.

The EMU-1 also has dedicated input connectors for connecting a tachometer.

Lastly you need to figure out how to configure the EMU-1. The EMU-1 has 6 gauge inputs, but they are generic inputs. To configure the EMU-1, you use the PC software that comes with the EMU-1 to say what engine sender is connected to each input. For example, you might connect gauge input #1 on the EMU-1 to the fuel sender. You use the PC software to set gauge input #1 to send NMEA 2000 fuel level messages, uand when the input reads 33 ohms broadcast tank full messages, and when it reads 240 ohms broadcast tank empty messages.

You‘ll also need to run NMEA cables between the Garmin and the EMU-1 and there are some details like cable termination that need to be followed.

If you are willing to pay for the Actisense devices, it might be time to talk with your computer nerd friends and see if they are willing to help out with the configuration. They might consider it an interesting challenge.

There are other engine monitoring devices available. The EMU-1 is just one example. But they all involve understanding how to connect your senders to the monitoring device and how to perform the configuration.

SIDEBAR: LIFELONG COMPUTER NERD...WHERE HAVE YOU BEEN ?

I need a personal/portable WiFi to connect to Roku on our boat 20" smart tv. Our marina has no wifi. We have 1000' forested hills 2/3 around our marina...beautiful, but blocks even local tv stations at the slip. My iPhone via ATT wants to bill me $40 a month additional to make the phone wifi. Phone receives 5 bars and I do get 7 locked wifi networks. Got to be a cheaper way to keep the ladies and little ones happy when docked on weekends between sailings or when they want to camp out overnight on the boat.

I am totally inert when facing this problem. Amazon shows dozens of portable personal wifi's. I don't understand the lingo. What can you suggest...?
 

mbp

Ericson 34
Would a surface mount tank sender work for the fuel tank? I'm getting something similar for my fresh and black water tanks.
If you are talking about the metallic strips that you place on the side of the tank, no. Those only work on plastic tanks, and your fuel tank is likely metal.
The tach doesn't work at all and the fuel and temp gauges are suspect at best.
Tachometers on diesel engines require special treatment. There is no ignition system on a diesel, so the engine speed is measured in another way. Some tachs sense the gear teeth on the flywheel either optically or magnetically. Other tachs count pulses generated by the alternator. In both cases, the pulses generated by the sensor are some multiple of the actual engine revolution. This is one of the things that you need to figure when programming an engine monitor like the EMU-1.

If the tach is not working at all, perhaps the problem is the sensor side of the circuitry and not the gauge. Even if you switch to a NMEA 2000 engine monitor, you’ll need to confirm that the sensor side works and tach pulses are getting generated. Trace out the circuit and make sure there are no broken or disconnected wires.

No boat fuel gauge is accurate. The oddball shape of the tank (because the fuel tank is put in some inaccessible location) means that the float type sensors can only provide approximations. Our boat came with a hand drawn gas gauge compensation chart. It is a picture of a gas gauge, and then drawn on top of the picture are arrows indicating where 20, 15, 10, and 5 gallons left really are. There‘s information about a more accurate fuel sender here and here.

You can use something like this to check your engine temp gauge. Just like your other gauges, you need to determine if the problem is on the sender/sensor side, or if the problem is with the gauge.
 
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