Crazy NEW interference on 520 with motorguide digital 109

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green weenie
Posts: 91
Joined: Fri Nov 10, 2006 4:30 pm

Crazy NEW interference on 520 with motorguide digital 109

Post by green weenie »

Just put on a 109 digital with built in transducer. Hooked up to three separate batteries with a ground between the cranking battery and the 36 volts. I now have horrible interference, never goes away while trolling motor switch is pushed. Screen is yellowed out from 100 percent all the way down to 30 percent sensitivity. I never had interference with this 520 before with an external transducer on a non digital tour 82. Any thoughts? Wes :cry:
civicrr
Posts: 364
Joined: Mon Aug 25, 2008 10:04 pm

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by civicrr »

I have had both the Digital Tour 82 with & without built in transducer. No issues related to trolling motor induced interference.

Not quite sure what you are saying about the batteries. Do you have four batteries total? Three for the trolling motor & one cranking? Or do you have three batteries total? I read somewhere that the Lowrance should not be hooked up to the trolling motor batteries. Should have separate cranking/electronic accessory battery AND separate trolling motor power source.
green weenie
Posts: 91
Joined: Fri Nov 10, 2006 4:30 pm

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by green weenie »

that is correct. I have 4 batteries. 36 volt in a series with 6 guage wire. separate 12 volt deep cycle for cranking, electrical including meters. i also have a 18 guage ground from neg of cranking battery to neg of 36 volt trolling baterries as I have always done for added ground. With this new motor, interference. Wes
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scottsweet
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Location: Campbell, CA

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by scottsweet »

You may have ground loop interference. The way to fixed it is to join the ground of your cranking battery to the 36V - (negative) side of the trolliing motor battery.

Before you do this, double check with Motorguide to ensure there isn't an issue with doing this. MinnKota used to have an issue but was later approved to be ok.

Scott
green weenie
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Joined: Fri Nov 10, 2006 4:30 pm

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by green weenie »

I believe that is what I have with the 18 guage ground from the cranking neg to the trolling neg. Thanks Wes
civicrr
Posts: 364
Joined: Mon Aug 25, 2008 10:04 pm

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by civicrr »

green weenie wrote:that is correct. I have 4 batteries. 36 volt in a series with 6 guage wire. separate 12 volt deep cycle for cranking, electrical including meters. i also have a 18 guage ground from neg of cranking battery to neg of 36 volt trolling baterries as I have always done for added ground. With this new motor, interference. Wes
Get rid of the added ground from neg of 36volt system to neg of cranking battery. It is causing the problem.

BTW, I don't believe there would be ground loop problems on a boat. Happens on, say a car, with stereo systems. That would be because of using the car body & chassis @ different points for ground - with current passing through car body & chassis. On a boat, the TM motor is its own system. Cranking battery & accessories are system with motor. They don't ground to the boat hull itself.
JLS (Jay Liu's Service)
Posts: 87
Joined: Sun May 08, 2005 7:53 am

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by JLS (Jay Liu's Service) »

Green Weenie, if your trolling motor is new, you can get interference until the brushes seat in. I have had that problem when I rebuilt some units.

JLS (Jay Liu’s Service) Trolling motor repair.
green weenie
Posts: 91
Joined: Fri Nov 10, 2006 4:30 pm

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by green weenie »

Its used, but newer. ill call you to see if it is still warrantied. Wes
jrbasspro
Posts: 459
Joined: Thu Jul 20, 2006 10:41 pm
Location: Lancaster CA

Re: Crazy NEW interference on 520 with motorguide digital 10

Post by jrbasspro »

is your powere wire connected to the same termnals as your trolling motor in the bow?

I ended running a seprate power wire all the way to the cranking battey and I have no issues. and run the wire on the opposite side from the trolling motor wires

Walt
listen to that gut feeling!!!

"keep it clean and dry"
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