Electrical GURU's I need your help

I have recently noticed that i have interference on my 998 SI unit when using the trolling motor. I just noticed cause i usually dont use SI when on TM as my SI unit in back and have different unit up front...usually have a buddy fishin in back and we switch it to 2d
I was fishing the other day had si unit turned so i could see from front and noticed then....
So i have 2 dedicated batteries. 1 for the 998 and 1 for the TM. They are the only thing on each battery.
The only connection between them is that i have a 2 bank minn kota charger connected to each battery. I have narrowed the interference to the charger....i can unhook charger connections from TM battery and no interference. The charger is NOT plugged in either. I have bought the ferrite chokes but no resolution. I like having convenience of just plugging up and ready but dont like interference.
Anyone have any help? I have read the rf thread.....

Tom

Can you see if the problem comes thru the ground side of the charger? Hook up the positive and leave ground unhooked and try this. Repeat with the power lead.

One lead is easier to fix than two. I have heard of this type problem before. Never heard the fix.

Ground side being the negative side of the battery being charged.

You can disconnect the charge cable via switch or by relay or by lead quick disconnect. These options will fix it. What you wanna do?

Do you have room for a second charger ... ??

Rickie

Switches are cheaper than chargers. :yikes:yikes You can use a switch remotely to operate a relay(s) to switch lead(s) or you can just use an wall 12v charger and plug it in and operate relays when you plug your battery charger in. Cheap fix either way. Disconnect or direct switch at lead is cheaper, but PIA.

I've got the same interference on mine Tommy. When you figure it out, just let me know what you find. I've been ignoring mine for the most part, but it does need to be fixed. I suspect it is either the on board charger or coming back through the US2. Both of these would be real easy to check. My plan was to pull the fuses between the starting battering and the charger. If that doesn't fix it I was going to disconnect the US2 transducer. If I beat you to finding my problem, I'll let you know. I suspect they will both be the same thing.

I ran a 18 gauge wire to the TM case to fix my us2 problem. This works best on most TMs. There is a lot of EMI being generated by commutation and PWM with no where to go (unless you have US2 which is another problem). The on board charger probably has a ac signal sneak path back thru the current sensing which would need to be open air isolated via disconnect.

My opinion and Ima sticking to it.

http://i188.photobucket.com/albums/z...ps1f5379fe.jpg

Well i checked with just power (+) connected and it did same..not as bad, but still present.
Im thinking of the quick disconnect from charger......
Attachment 196724
Would this work? Just wire up charger leads to one end then other end to battery....unhook when fishing when back just reconnect when charging others

Tommy, that should work good for the power. I've been thinking about what Tom said about the relays, and if it is the charger that is the problem, I'll hunt up a 12vdc wall transformer and put normally open relays on it. When I plug the charger in, I'll plug the relay transformer in at the same time. Are your units networked and are you using the US2 transducer on the trolling motor?

If mine happens to be the US2 transducer, I'll add an external transducer to see if it will help. I've been on the lookout for another HDSI transducer anyway. I just hate to pay $200 for the transducer alone. When I think about 200 bucks for a transducer, I'm thinking I can sell the 798, add the 200 bucks I would have spent on the transducer, pay this much down on a brand new 1199 and then finance the rest of it for $19.99 a month for 7 years. :biggrin

Is yours doing it out of the water?

I will be going thru this noise stuff again when or if the Ulterra ever shows up. It has US2. The relays simplify life. I forget to unplug things.

Im not understanding the relay thing...pics work like a million bucks for me. Show me one and how you would wire it
Happens both on water and in shop :)

I'll try to check mine tomorrow, time and weather permitting. Does this make any sense? You could use a DPST relay also.

Attachment 196768

Where/how did you run wire cane pole when you wired to TM housing?

Quote:

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Originally Posted by RCC

I'll try to check mine tomorrow, time and weather permitting. Does this make any sense? You could use a DPST relay also.

Attachment 196768

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Right on.

I looked at a tabletop type power supply. They have a cord for power and a cord for output. 500 ma would be just fine. I will mount the power module on top of my on board charger prob with Velcro. I will cut the power plugs off both and splice the power cords or join the wires in a new ac plug. This way I ain't gotta fool with but 1 cord. I don't worry about a warranty. Ain't got one anyway.

Quote:

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Originally Posted by tommyboyrn

Where/how did you run wire cane pole when you wired to TM housing?

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My electronics were on their own battery up front. This was on my War Eagle Predator. I removed the front minner bucket and made a battery compartment. I ran a wire from the skag up thru the slot on the terrova shaft to the ground side of the up front battery. The ground side of this battery was also tied to the TM battery negative at the TM control board. This worked for me. None of the ferrite beads I tried stopped the noise completely.

EMI/RF noise is inherent. You can't really stop the noise, you can only mask it.

I have no cue what I will have to do with the Ulterra. It ain't got a groove in the shaft so I am told.. My pondtoon has no wiring channels front to aft. I will probably have to add one. PIA though.

My noise is coming through the US2. I was sure hoping the link was the charger. I haven't finished testing yet. I tore down my setup before I thought things completely through. My first thinking was that it was coming from the US2 which is connected to the 998 and then across the ethernet and jacking up the SI on the 798. I gotta go lick my calf over on this one. It may be coming across the power of the 998 to the 798 which are bridged. Gotta hook everything back up except the ethernet cable and see what happens. I sure hope it's coming across the power. I think that would be some easier to deal with.

Ain't it purty?

Attachment 196893

The bad news is that once the interference gets to the 998, it appears to travel back to the 798 both on the power wires and the ethernet cable. The only way I can be sure of this is to put the 998 or 798 on a separate power source and see if the interference is the same across the ethernet cable as it was with a common power source. I do have a non-hd side imaging transducer laying around somewhere. I guess I could hang it on the TM and see what happens. I would really prefer to put a hdsi transducer on the motor. I think I'll tell my wife that a pair of ONIX units would fix this.

Here is the interference from the US2 with the charger and ethernet disconnected. It is traveling from the us2, to a 998 across the power wires to a 798. The 998 running 2d is OK.

Attachment 196900

Canepole, when you ran wire from skeg, up shaft and to battery you had that connected to TM control board as well....is that the ground connextion at top of TM or in the footpedal housing?

I hooked on the power board. I tried several places, but this point gave best results. That US2 is a booger. This connect point is the same place near where the US2 fuse wire hooks. US2 wire is internal vs wire I ran external. Same point electrically. Figure it??

This has quickly become a PITA
I went and got some quick connects like i have pictured....wired up and checked both sides with VM...everything checked out...then i connect them and plug charger in and friggin charger now says "check connection". I again checked both sides and im getting everything to work up to the point i connext the 2 quick connects.....AAAAAAAAAGGGGGGGH
So i go get battery doctor master switch thingy and works great to cut power on/off but when i switch to "off" and check TM on 998....same interference problem.....so after 3 hours of tinkering and still back to square 1
I dont understand how it could be losing enough juice in connection to trip charger to check connection....
Now im seriously considering relay but since its all wired together like the above master switch im afraid it to would show interference

Im thinking of doin away with on board charger and go back to old way of doin things.....

I had no problems with adding a switch to mine (Power Pro). Mine flashes a fault code when I have a bad connection. Usually a fuse holder get corroded a little and causes the fault.

Adding a little wire length shouldn't matter since you can buy a 10 foot extension battery cable (to battery) and the charger still works fine.

No make sense.

I solder all my connections. I do not trust crimps. I do use crimps on a temporary basis.

Thanks guys....will dive back into it again this week

Would using 2 spst switches work? That way both (+) and (-) sides isolated through switches? Thats been my problem with the battery doctor thing is that through one cixuit the interference remained.....

Yes. That would work. I users a dpdt throw switch from Radio Shack.

Yes. That would work. I users a dpst throw switch from Radio Shack.

Ok thanks.....will give that a try

NTE54-004 - 15A Bat Handle Toggle Switch : Toggle Switches | RadioShack.com

Bat handle, and I put a rubber boot on the bat handle I got at Car Quest.

Ok well i wired up a dpst switch from autozone and.......IT WORKED!!!
No more interference what so ever...put switch on battery box.....when charging mode switch will be lit and flip switch to off and circuit disconnected from charger.
Many thanks guys for your help i greatly appreciate it
Attachment 197550Attachment 197552

Great!!

Excellent. That will work great.