Can you sheild wires to prevent electircal noise?

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

1) i will try a ground and power wire twisted from the battery and hook up to the fishfinders wires.

2) i will try the noise filter however i installed a clamp fitler and didnt work last time i was out,
which wire or location should i clamp the noise suppressor at?

3) then i will try the spark plugs

I will report back with my findings, i plan on going through the grounds with a fine tooth comb and check for corrosion. I just cleaned the connections running to the battery though.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

Bring you your twisted pair directly back to the battery and that will be your only ground point. Don't ground again at the helm.

Fuse the positive wire at the battery.

Run your transducer cable away from all other wires if possible. Your fish finder instruction likely already advised this.

Typically, a ferrite bead or "clamp filter" in your case would be as close to your device as possible. The problem you are experiencing is probably at a lot lower frequency than the stop band of the filter.

EDIT: How's searching for your even harmonics coming along? LMAO

 

[Fed]

Re: Can you sheild wires to prevent electircal noise?

When I'm running my sounder and start my motor I get a lot of lines on the screen but they disappear fairly quickly, I put it down to running the sounder in auto mode & it taking a short time to lower the gain to the appropriate level.
Every sounder I've ever owned will show hash on the screen if the gain is set too high.

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

Run your transducer cable away from all other wires if possible. Your fish finder instruction likely already advised this.

EDIT: How's searching for your even harmonics coming along? LMAO

Problem is all the wires run up the starboard side of boat though a hole to he fuse box under dash. i have the trans wire seperated from the other wires but where it lies inside the hull i have no idea haha

Yeah about them Harmonics....crickets.........wait..wait... more crickets still going in my head.

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

When I'm running my sounder and start my motor I get a lot of lines on the screen but they disappear fairly quickly, I put it down to running the sounder in auto mode & it taking a short time to lower the gain to the appropriate level.
Every sounder I've ever owned will show hash on the screen if the gain is set too high.

i have a lowrance elite dsi 5, i dont have those settings unfortunetly. there is a noise reduction but even with it on no luck.

 

[dingbat]

Re: Can you sheild wires to prevent electircal noise?

Problem is all the wires run up the starboard side of boat though a hole to he fuse box under dash. i have the trans wire seperated from the other wires but where it lies inside the hull i have no idea haha

I break every rule in the book and I don't have a bit of problem.

In one 4? rigging tube I have, 2-#10 power cables, a #8 ground cable, a 1kW transducer cable, a NMEA 2000 backbone cable, the main control harness and a paddle wheel cable.

Power distribution for the entire boat comes off the house terminal on the on-off switch. CD, VHF, Sounder, GPS, and 2000 backbone all come off the distribution panel at the helm. No noticeable RF in any of the systems. The only thing of note is that the sounder and GPS OEM power cords and the transducer cable all have OEM EMI filters on them. Both units ahave separate earth ground connections.

I'm an ME with a background in metallurgy and non-contact thickness measurements so what do I know. But?. The first thing I would have done is to start eliminating variables.

Connect the sounder, both positive and negative leads to a completely separate power source and disconnected the transducer. Use a battery charger if you need to. Run the boat. If you still have noise, you have sounder issues. If the noise stopped, connect the transducer and see what happens. If he noise returns you narrowed it down to the transducer cable. Nothing on the transducer cable, it?s a power issue.
Take the belt off the alternator. Did the noise go away?

I chased a similar problem for a guy and come to find out he was using the wrong spark plug wires. Your it doesn?t work, now it works bettered scenario would lead me to an issue with the alternator.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

Connect the sounder, both positive and negative leads to a completely separate power source and disconnected the transducer. Use a battery charger if you need to.

I agree with this method as well. Probably wouldn't use a battery charger since those put out a lot of noise.

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

i dont have an alternator, i do have a stator. But i will use your advice about a separate power source i do have some battery chargers. ill check that out as well.

 

[dingbat]

Re: Can you sheild wires to prevent electircal noise?

I agree with this method as well. Probably wouldn't use a battery charger since those put out a lot of noise.

If the unit can?t deal with what little noise you would get off a battery charger, someone didn?t do such a swell job of designing the unit?s power supply circuitry and you could be chasing your tail.

Plug and plug wire issues typically make the unit RPM sensitive. With a stator I would start looking at the voltage regulator or the rectifier, if the rectifier is separate from the voltage regular. The "performs better later" has me somewhat puzzled. Typically performance deteriorates as components heat up and start to act up.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

If the unit can?t deal with what little noise you would get off a battery charger, someone didn?t do such a swell job of designing the unit?s power supply circuitry and you could be chasing your tail.

Depends on if the battery charger uses a full or half wave rectifier on its output. If its a half wave, the huge ripple that may be on there could well mess up the test.

On the subject of rectifiers, a blown rectifier section in an alternator or an outboard charging system could contribute greatly to the ripple put out by it and be causing the noise problem as well. Measuring the output of the charge system with a multimeter set to AC should show little or no AC ripple.

The finder should be able to be hooked up and work without any noise filters.

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

Measuring the output of the charge system with a multimeter set to AC should show little or no AC ripple.

The finder should be able to be hooked up and work without any noise filters.

i have a multimeter if you guys have any tests for me to run please let me know.

I WILL BE WORKING ON THIS ISSUE MON AND TUESDAY, SO CHECK BACK FOR UPDATES PLEASE...

i have been told locally the same i shouldnt need filters here, but if it solves the problem for cheap ill do it.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

Filters are a band aid for something that is really wrong.

Measure the voltage at the battery with the meter on AC at various RPMs. Should be less than 0.2V(200mV) or so. You may want to measure it with various loads on it. Since it sounds like it does this more at startup, the time when your charging system is putting out the most current is at that time because it is charging the battery from running the starter.

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

UPDATE W/PICS: I cleaned up the gas tank connections,grounds for the motor, and acouple other corroded wires. did the twisted wire trick and completely wire away from other wires. Haven't ran the AC test yet but will do tomorrow unfortunately wont know if this solves the problem until Sunday.

BIG QUESTION: On the first pic is of bilge area. There is i suspect 2 ground wires going to 1) mount for my livewell pump
2) to the drain hole

They look really bad shape can i relocate them??

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

If that is your transducer cable, I wouldn't be running your power/ground next to it. Also, I prefer a tighter twist. Did you try the drill trick I mentioned above?

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

Here is a link to a video, i have my multimeter set to ac. Without the motor turned on it averaged .27 .

http://www.youtube.com/watch?v=MYg4V0Tt0mc

please report back with results if you think i am experiencing engine noise.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

Without the motor turned on it averaged .27 .

Without?

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

Without?

correct with engine not runnning. just hooking the multimeter up to the battery. Seems to be the same #'s with the engine on idling as well though.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

What bothers me is that I saw a reading of 1V there when you revved it up which is way too high.

Reading 0.2V with the engine not running seems almost impossible. Was anything else on at the time? The leads were directly on the battery posts right?

 

[Bustedknuckle84]

Re: Can you sheild wires to prevent electircal noise?

Bruce;
I had the fish finder,radio,and stereo on when hooking up directly to the terminals on ac without motor running.

the 1v reading is after letting off the throttle youll hear the knocking sound and the 1v seems consistant with that knocking sound, if you slowly rev up it stays around the .2 .

i will keep all electronics off and re test.

 

[bruceb58]

Re: Can you sheild wires to prevent electircal noise?

Your leads were right on the battery?