Lost my NMEA network somehow

[schinkr1]

Not a new install, was working just fine. I noticed my Point 1 was not working, then while troubleshooting confirmed that nothing on the network is seeing each other (HDS Live 12, HDS Live 9, Ghost, Point 1). Under the network settings I tried the Auto Config option and it removed all the devices that were networked and now each unit only can see itself. My NMEA gets power at the main console. I pulled the fuse from the power block to the NMEA network and confirmed it is getting power. Not sure what else to check. Seems like a pretty straightforward setup. Thoughts?

[schinkr1]

Well, I took every connection off and plugged them back in and now it's working. Happy it's working, but was hoping to find a root cause. All the connections felt solid.

[Team Colibri]

Even though the last generation NMEA-connectors (Micro-C) are waterproof, it is typically a good idea to pick them apart once a year or so and give them a dose of contact-spray. The current going through NMEA is low, so it does not take much to stop the whole network.

[schinkr1]

Network went out again. I picked up some contact-spray. Have a few questions though. Included a layout of my network setup. I will clean all the contacts, but looking for a way to systematically test each component to see where the issue is. I'd like to get to root cause, whether it's a specific connection or cable. I'm asking if I could use a multimeter to test each connection in the network or if this is an all or nothing deal i.e. if one connection is bad they are all bad.

NMEA2.jpg

[schinkr1]

Even though the last generation NMEA-connectors (Micro-C) are waterproof, it is typically a good idea to pick them apart once a year or so and give them a dose of contact-spray. The current going through NMEA is low, so it does not take much to stop the whole network.

I'm still having issues. Can you take a look at the pic I uploaded and give some thoughts on how to troubleshoot? For example, can I take a multi-meter and test the voltage at each connection or is it like the old x-mas tree lights where 1 light (circuit) goes out and they are all dead?

I found this old post http://www.bbcboards.net/showthread.php?t=668979&page=6 but the diagram indicated 'Red' connector and mine are black. The boat, graphs and network are all less than a year old.
Thanks

[schinkr1]

Took everything apart and sprayed all connections with contact spray as recommended. Also moved one of the T's from the console to the back of the boat, which eliminated one cable. Figure the less components that can fail the better. So now I have 2 T's at the bow, 2 T's at the console and 2 T's at the rear of the boat. Everything is working again in the garage. Will see how it holds up on the water. I'll be on the great lakes for two weeks in July and would hate to be on big water without Point 1. So general question, if there is a fault at say the bow of the boat, will that render the whole system down? The network gets power from the console, so wondering if part of the network would still work or if it would all be down.

[Tim619]

If it were mine, I'd pull the network apart, start with a bare minimum of components on the network and add back items one at a time until the network failed again. Hopefully that will point isolate the bad component.

[DR. DROP]

Going back to your first post.
Did you look at the device list on both Lives?
Where you just looking at one unit and see there was nothing on the network?
I got water in my 9 Live on the bow. Wiped out the nmea circuit. It showed faults on the Bus.
My other units showed the network.

[schinkr1]

Going back to your first post.
Did you look at the device list on both Lives?
Where you just looking at one unit and see there was nothing on the network?
I got water in my 9 Live on the bow. Wiped out the nmea circuit. It showed faults on the Bus.
My other units showed the network.

Yes, I looked at both units. Also ran the auto config on both and all it did was remove the devices that were on the network. It's working now, in the garage, but my confidence isn't high that it will stay working. I planned to build it back piece by piece until it stopped working to find the bad component, but it appears to be an intermittent problem since it's working again with all the pieces connected.

[Moonlighter]

Looking at your diagram, there is only 1 terminating resistor shown. There should be 2 unless one of the devices connected has the TR incorporated in it.

Networks that aren’t terminated correctly can sometimes work and sometimes not, but sooner or later you can be sure you will have problems.

[Bill Reynolds]

These 2 screen shots should be helpful in diagnosing the voltage and resistance in the backbone.
Question:
In the second pic, you do not show a termination resistor on one end but the other pic shows one???
you don’t mention the brand of boat but if this is a Ranger, I would check to be sure there is a terminating resistor in the bilge. I have seen two occasions where they were not properly terminated from the factory.
In both cases, the network was erratic like you describe.

[DR. DROP]

To me if you lost all the devices on the network.
I would think you have a connection problem at the tee where the 12v power hooks up.
Can probably wiggle some wires around while watching your device list or bus state on your unit.
Unless you swapped the bad tee around to a different posision

[schinkr1]

Here is a clean picture. I do have 2 terminators. Bill, you are spot on. This is a Ranger and I didn't realize I had a temp sensor in the bilge with a T when I bought the boat, so ran another line. I tore everything apart last night and cleaned up the wiring, so it looks like the new image posted below (moved a T from console to bilge and connected Point-1 to the T in the bilge, removing the extra cable I installed). I'll take the boat out tonight and see if it stays working on the water. Really appreciate all the feedback and the detailed diagnostic diagram.
Network.JPG

[Bill Reynolds]

You should be good to go now. I did the same as you on my boat and a friends. I went through a lot of mental gyrations assuming Ranger did a correct installation but they did not. I am not saying that all the Ranger installations were missing the terminator but I know of two. There is an inline termination resistor that I thought they may be using, but when I did the resistance test, it was clear that it was not there.

Edit: You may have to calibrate the Point-1

[schinkr1]

I absolutely hate this network. It worked in my garage, I got to the lake and it stopped working again. This is my 4th wasted fishing trip. I disconnected the rear two T's (Temp sensor and Point 1) and put the terminator on the cable. Turned everything on and bingo, the two graphs and Ghost were on the network. I was happy because I thought I at least isolated half the network into good and bad. Just to be sure, I reconnected the rear two T's and everything showed up again on the network. I feel like I'm chasing ghosts.

[NoCAL]

You photo in post 13 is an example of a perfectly configured NMEA network. If that isn’t working, there has got to be a bad component. These networks are not that sensitive! I’ve had mine in the boat since 2008, just keep adding Ts and new components. Personally, I’d take off the back two Ts, replace the terminator and go on your trip. Once you are sure the network is working, add in the temp sensor. Make sure it is working then add the Point 1. Your issue sounds like it’s at the rear of the boat, so start by isolating the connections back there.
How does the fuse block receive power? Are all the units and the network on the same block and do they start up at the same time. Is there a cutoff switch that you turn on to supply power to the block?

NoCAL

[Bill Reynolds]

My memory is really foggy but several years ago, when I was having all the trouble with the Point-1 install I read that if you left the Point-1 powered up for long periods it would or could go to sleep. To get the network to recognize it again, you had to physically disconnect from the tee and reconnect it.
This made no sense but I did have to do this after leaving my network powered up for a long period. It only happened a couple times and there were a lot of other things happening so I can’t say for sure that this was the problem.
I normally turn off all power to the boat with a master switch but sometimes I forget.
Perhaps someone that is more knowledgeable can weigh in.

As NOCAL said, your current NMEA setup is correct and his suggestion to find the bad component is spot on.

Edit: Do you have a Level1 or above MercMonitor supplying engine information? If so, there is a NMEA power supply built into that wiring harness. When I installed mine, Don had me hook the ground wire of that NMEA power source to the power source ground to the NMEA tee connection. He said that even though we were not using the power supply in the MercMonitor, we needed to connect the two grounds to prevent a ground loop.

[schinkr1]

I always cut power to the boat when I'm not fishing (Ranger switch to kill power). I don't think it's a Point-1 issue since the whole network goes out and it goes out within minutes of getting to the lake. Also not sure I can say it's an issue with the back of the boat since the problem is so intermittent. I just happened to start with disconnecting the rear half of the network. In terms of power, it's a Ranger and behind the console/steering wheel, there is a buss bar. I physically inspected the connections and checked with a voltmeter. I think you guys are onto something with it being a component. I might go buy one of those network in a box kits and just start replacing parts. Hate the idea of pulling new cables, but maybe starting with T's and terminators.

[bloodman]

I do not see how it could be anything but the power connection. The fuse link is the first place I'd check and replace.

[Bill Reynolds]

Do you have a Level1 or above MercMonitor supplying engine information? If so, there is a NMEA power supply built into that wiring harness. When I installed mine, Don had me hook the ground wire of that NMEA power source to the power source ground to the NMEA tee connection. He said that even though we were not using the power supply in the MercMonitor, we needed to connect the two grounds to prevent a ground loop.