NMEA2000 Network - Bus Off

[snookonfly]

All of a sudden the point1 stopped working this weekend. Checked the status via the diagnostics page on the HDS Live and it says "Bus Off"

I am still running the 22.1 update so this is not tied to the new update.

Where do I start to troubleshoot?

[kennybryan]

Fuse on the power panel then the in line fuse. Next check all terminators are secure.

[snookonfly]

Fuse on the power panel then the in line fuse. Next check all terminators are secure.

Thanks, KennyBryan. I didn’t install the network portion of my setup and haven’t found that inline fuse yet. It’s not in the battery compartment. Will need to dig into the console and the bow.

On the day it stopped working, it was at the end of a tournament day where I had ran my battery down extremely low. Not sure if this makes any sense but could the low voltage caused the fuse to blow?

I’m really hoping that the fix is a fuse or lose connection.

[Whistler]

Thanks, KennyBryan. I didn’t install the network portion of my setup and haven’t found that inline fuse yet. It’s not in the battery compartment. Will need to dig into the console and the bow.

On the day it stopped working, it was at the end of a tournament day where I had ran my battery down extremely low. Not sure if this makes any sense but could the low voltage caused the fuse to blow?

I’m really hoping that the fix is a fuse or lose connection.

Actually, I believe the low voltage could potentially cause a fuse to blow. Your NMEA network requires a certain amount of power. To get that power the voltage * current is required. As your voltage drops, current in the circuit has to increase to supply the same amount of power. So, if your voltage dropped to a low enough value and your fuse was rated at a low enough current it is possible. Not sure if it is likely, but is possible.

Here is an example:

If your NMEA network requires 10 watts of power (it probably doesn't) and your fuse is rated at 1 amp.

12 volts x .8333 amp = 10 watts

But, if your voltage drops to 9.5 volts this will cause your current to increase

9.5 volts x 1.053 amp = 10 watts

Now the real question is would 1.053 amps cause your 1amp fuse to blow? My guess is probably not. And if they fuse is larger than that then it's hard to image a scenario where it would.

Just looked up the typical power consumption of the point 1. Lowrance lists it at <2W. If you plug those numbers in above you will quickly find that the the currently required will drop to 1/5 of my example. Making it very unlikely that low voltage caused the fuse to blow.

[snookonfly]

Actually, I believe the low voltage could potentially cause a fuse to blow. Your NMEA network requires a certain amount of power. To get that power the voltage * current is required. As your voltage drops, current in the circuit has to increase to supply the same amount of power. So, if your voltage dropped to a low enough value and your fuse was rated at a low enough current it is possible. Not sure if it is likely, but is possible.

Here is an example:

If your NMEA network requires 10 watts of power (it probably doesn't) and your fuse is rated at 1 amp.

12 volts x .8333 amp = 10 watts

But, if your voltage drops to 9.5 volts this will cause your current to increase

9.5 volts x 1.053 amp = 10 watts

Now the real question is would 1.053 amps cause your 1amp fuse to blow? My guess is probably not. And if they fuse is larger than that then it's hard to image a scenario where it would.

Just looked up the typical power consumption of the point 1. Lowrance lists it at <2W. If you plug those numbers in above you will quickly find that the the currently required will drop to 1/5 of my example. Making it very unlikely that low voltage caused the fuse to blow.

Thanks Whistler :)

I hope i don't need to replace the whole cable! Would love for it to be a fuse.

[bloodman]

You need to check the power connection to your NMEA.
I traced my NMEA connection problem for a long time. It was one of my 12 Lives that if I disconnected from the system, my problem went away.
In the brief 23.3 update period, my system has performed well.
Might be your Live doing it

[snookonfly]

Checked all the connections and cleaned them with rubbing alcohol. Booted it up and the bus is now powered on. Left it powered up for about 30-40 minutes with no problems. Unfortunately, the network does not see the Point 1 in the data sources list.

I ordered a new point 1 to test if my point1 has gone bad.

[CatFan]

Actually, I believe the low voltage could potentially cause a fuse to blow. Your NMEA network requires a certain amount of power. To get that power the voltage * current is required. As your voltage drops, current in the circuit has to increase to supply the same amount of power. So, if your voltage dropped to a low enough value and your fuse was rated at a low enough current it is possible. Not sure if it is likely, but is possible.

Here is an example:

If your NMEA network requires 10 watts of power (it probably doesn't) and your fuse is rated at 1 amp.

12 volts x .8333 amp = 10 watts

But, if your voltage drops to 9.5 volts this will cause your current to increase

9.5 volts x 1.053 amp = 10 watts

Now the real question is would 1.053 amps cause your 1amp fuse to blow? My guess is probably not. And if they fuse is larger than that then it's hard to image a scenario where it would.

Just looked up the typical power consumption of the point 1. Lowrance lists it at <2W. If you plug those numbers in above you will quickly find that the the currently required will drop to 1/5 of my example. Making it very unlikely that low voltage caused the fuse to blow.

Devices like these don’t work that way. When voltage drops on almost everything, current also drops. The only exception most people will ever encounter are AC motors which will draw as much current as they can if they can’t maintain their RPM, whether it’s because of low voltage or excess load.

[snookonfly]

Update…Turns out the point 1 failed. I bought a new one, installed it and all is working great!

[bgibson]

Update…Turns out the point 1 failed. I bought a new one, installed it and all is working great!

Great update! Glad you figured it out!

[yupitsme]

Update…Turns out the point 1 failed. I bought a new one, installed it and all is working great!

Just as a test... Reconnect the old Point 1 and see if it works now. You might end up with a spare Point 1. You don't have to re-install it. Just see if it's visible on the NMEA network.