Chartplotter turns off on engine start

[chart5011]

My Garmin 192C Chart Plotter goes blank if I start the engine on 'Both', (can't remember if it does it on just the engine battery). I take it that on starting, the current to the Garmin drops below a certain point and it cuts out. Is this usual?
It is wired to the same switch as the Stowe Echo Sounder/Speed/Log which doesn't cut out.

 

[oldsaltoz]

Low voltage.

 

[aslabend]

It does sound to me like you are suffering a voltage drop which affects the gps more than the log/echo. I Had a similar problem with a similar set-up, GPS+log/echo+gps repeater all running off of the same supply. I replaced the one supply with two thicker wires to solve it.

 

[MoodySabre]

My Garmin 120XL GPS does that too.

 

[tillergirl]

Bl**dy good thing too, Roger!

 

[temptress]

Garmin is VERY sensitive to voltage drops below 11v

The Garmin is VERY sensitive to voltage drops below 11v the instruments are not so sensitive.

Do you have a digital voltmeter?

Take a voltage reading at the Garmin when you are starting the engine and observe the volts, then do the same at the batteries you should see different numbers. If that is the case and the voltage at the batteries (or battery switch) does not drop below 11v then put the Garmin on it's own supply (with an inline fuse!) from the batteries.

If the volts at the batteries drop below 11v then you have other problems.

 

[MoodySabre]

Bl**dy good thing too, Roger!

I can't find my way up Bradwell Creek without it

 

[Poignard]

My Garmin 120XL GPS does that too.

So did mine - until I fitted a new battery to my boat. Now we can have the lights on longer and the engine starts more easily, as well.

 

[GrahamHR]

My Navman 5600 Chartplotter used to do that, yet the Garmin 250 Fishfinder didn't; both fed from the same auxillary fusebox ( seperate fuses), both with similar sized cables and connected to the same -ve busbar. If Garmin products are sensitive to voltage drop ( "below 11v"), then Navman must be even more so!

I couldn't find any bad connections that gave any appreciable voltage drop. The two main batteries are in good condition. I eventually got round it using a small ( domestic alarm back up) lead / acid 12Volt battery and a suitable sized diode. The diode is in line with the main +ve feed to the Navman. The extra battery +ve is connected after the diode (with a fuse), with the -ve terminal to a busbar. If there is any voltage drop as the engine is started, the Navman does not experience it, as the voltage is maintained by the smaller battery; there is a voltage drop across the diode, but the small battery is still charged, albeit maybe not to full capacity.

 

[Scotty_Tradewind]

My Garmin 192C Chart Plotter goes blank if I start the engine on 'Both', (can't remember if it does it on just the engine battery). I take it that on starting, the current to the Garmin drops below a certain point and it cuts out. Is this usual?
It is wired to the same switch as the Stowe Echo Sounder/Speed/Log which doesn't cut out.

I'm no electician but surely if you have a seperate 'engine' battery then if wired correctly the instruments running off the 'domestic' battery shouldn't suffer a volt drop when the engine is started?

I would ensure you are running two seperate circuits from your batteries.
One a designated engine start battery, the other a domestic, nav' and instrument battery.
Then a switch which allows you to join the engine and domestic batteries together for emergency engine start up only.

 

[Skylark]

Raymarine, too

A fairly easy problem to define but not see easy to solve!

My boat has B&G instruments, a Navman GPS feeding a Raymarine plotter with a Raymarine plotter/repeater on the console. I have the same problem.

I've replaced both batteries (when the boat was 5 years old) but not cured the problem.

After a day sail, worst case is that it all shuts-down on starting the engine. If I've been motoring for 8 hours, the electronics may not be affected at all but the battery voltage is undoubtedly very high. Anywhere in between, the plotters will go down first, then the GPS, lastly the instruments. I've tried to clean all terminals and sprayed miracle cures around electrical endings that can't be reached but all to no avail. Can't find the elusive cause for a voltage drop. I contacted the original owner and he did not experience the issue.

Good look with your search, post again if you find the culprit!

David

 

[MoodySabre]

I'm no electician but surely if you have a seperate 'engine' battery then if wired correctly the instruments running off the 'domestic' battery shouldn't suffer a volt drop when the engine is started?

It doesn't work like that for most people who have a 1-both-2 switch. Put it on to battery1 (starter batt) and switch on everything, start engine, GPS switches off, after running engine for a while to recharge batt 1 then switch to batt 2 to run domestics/instruments whilst engine is off.

Answer is of course to turn nothing on until the engine is running.

 

[Dipper]

My Garmin 192C Chart Plotter goes blank if I start the engine on 'Both', (can't remember if it does it on just the engine battery). I take it that on starting, the current to the Garmin drops below a certain point and it cuts out. Is this usual?
It is wired to the same switch as the Stowe Echo Sounder/Speed/Log which doesn't cut out.

My Garmin GPS also does that but on a single battery. I haven't tried it with both batteries on. The problem is that if I then wanted to send a distress signal on my DSC VHF, there wouldn't be a position transmitted unless I remembered to switch the GPS on again.

 

[Refueler]

It's very simply that engine starter is dragging voltage down when starting engine.
It's a common problem as you can see from number of posts with similar.

Long time ago someone posted on the old forum a cure by using a capacitor in parellel ... Now I cannot remember the description and how to connect - but as I remember ... the capacitor remains charged up while all is normal. Hit start button and voltage drops ... capacitor then feeds GPS / instrument just enough to keep it going. I'm sure some electronics wizard can come up with suitable ...

The other way of course is to do as I do - have GPS of domestic and start on other battery. If you are really clever - you could have a car headlight relay wired in ... so domestic battery is disconnected from other battery until alternator spins up and starts charging - that way both batterys get charged but you don't interfere with gear connected to domestic battery. I have my cool-box wired in like that.

Basically there are loads of ways to stop the GPS cutting out ...

 

[Amulet]

Normal, probably not soluble, not really a problem. Start only with the engine battery to avoid. Same reason as your car lights go dim if you crank the engine. I have a setup with computer attached to hand-held GPS, both with internal batteries but normally powered from the boat's 12 volt system. They keep going on their internal batteries when I start the engine, but the massive current surge causes so much electronic disruption that it almost always screws up the computer/GPS communication, which then has to be reconfigured.

 

[WindermereColvic]

Capacitor set up is here:
http://www.ybw.com/forums/showthread.php?t=210846&highlight=Capacitor
Looks like quite a ingenious little arrangement.

 

[stav]

I had a similiar problem with a standard horizon plotter. In the end I seperated the starter and domestic batteries and ran a direct feed from the starter to the engine start battery and then fitted a charge splitter. I left the selector switch in so I can still switch between the batteries I also added a sterling regulator boaster thing.

Quite a bit of work but pleased with the set up as I do not have to worry which position the selector switch is in as I know both batteries will be charged once the engine is running. Also the power to start the engine comes from the starter battery and small amount of current to activate the solenoid comes from the domestic batteries. Though I have to confess the positive feed to the engine starter does not have a fuse in it but I did run it through plastic pipe and fitted it in such a way that if it drops of it should drop down from the engine.

Good luck with it though.

 

[Erwin Swart]

Have the same problem. Talked with a technicien and problem is probably the wiring. Wiring in general is too thin, so replacement of the wiring (from battery to the main board) to ie 70 mm is the solution.

grtz

 

[beyondtheblue]

My Lowrance did it.... I turned the screen brightness down one notch and it sorted it.

 

[johnalison]

You should all consider yourselves lucky. When we had Decca it used to take another 20 minutes to find itself again. A reserve battery was the most popular solution at the time, or direct wiring to a service battery.