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Old 06-02-2010, 01:16 PM   #1
Fish'n John
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Default Trolling motor expertise

I have a '98 Glastron "Fish and Ski". It has a 24V Min Kota 64lb trolling motor operated through a Dual Phase II on-board battery charger/bat. system interlink (not made any more). I imagine that this is a set-up like found on some Bass Boats. I can only get 12v output to the motor which is only useful if there is no wind. I have tried wiring it direct to 24v but I end up blowing fuses. I am at my wits end trying to figure out if the problem is in the charger, the trolling motor or the connections. I have tried Fays Boat Yard, who seem like good local experts, and they were little help on this issue. I have tried online to find a nearby shop that works on Bass Boats without success.

Does anyone have an idea where to turn for help?
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Old 06-02-2010, 02:05 PM   #2
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There used to be a Nissitissit trolling motor repair business down near Nashua somewhere.....named after the Nissitissit River. Maybe try 'Nissitissit trolling motor repair' in a search engine and come up with something?
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Old 06-02-2010, 02:08 PM   #3
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Welcome to the Forum John. I have no experience with trolling motors or anything else on a boat that uses 24 volts. First I must assume you have TWO 12 volt battery's in the boat which can be "Tapped' for 24 volts by using the two battery's in Series. Normally the two batterys would be used in Paralell for everything else in the boat.

I suspect the circuitry associated with the trolling motor allows this..without subjecting ANY of the rest of the boats appliances to 24 volts....which would blow fuses at the least. So this leads me to believe that the circuitry that you mention ..."that is no longer made", needs to be replaced with somehting else. I suspect a compatible item (different brand) should be available from someone that services bass boats.

There must be a bass boat dealer somewhere around the lake. In the meantime, try this link as a start. They sell bass boats.....among other things. NB

http://www.dougrussell.com/

EDIT: Maybe not. I may be thinking of a place just down the street from Doug Russell which i thought was an annex. I'll have a look and get back.

EDIT 2: Here is the place down the street from Doug Russell.

http://www.boats.com/sites/marineusa-worcester

EDIT 3: Try Google: "Bass Boat Dealers, Winnipesuakee, NH" I found a bunch.
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Old 06-02-2010, 03:25 PM   #4
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Quote:
Originally Posted by fatlazyless View Post
There used to be a Nissitissit trolling motor repair business down near Nashua somewhere.....named after the Nissitissit River. Maybe try 'Nissitissit trolling motor repair' in a search engine and come up with something?
It looks like Nissitissit trolling motor repair has been out of business for awhile and they have abandoned their web address. Good thought though. Thanks. I haven't really searched specifically for trolling motor repair businsses. I'll give it a try.
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Old 06-02-2010, 03:38 PM   #5
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Originally Posted by NoBozo View Post
Welcome to the Forum John. I have no experience with trolling motors or anything else on a boat that uses 24 volts. First I must assume you have TWO 12 volt battery's in the boat which can be "Tapped' for 24 volts by using the two battery's in Series. Normally the two batterys would be used in Paralell for everything else in the boat.

I suspect the circuitry associated with the trolling motor allows this..without subjecting ANY of the rest of the boats appliances to 24 volts....which would blow fuses at the least. So this leads me to believe that the circuitry that you mention ..."that is no longer made", needs to be replaced with somehting else. I suspect a compatible item (different brand) should be available from someone that services bass boats.

There must be a bass boat dealer somewhere around the lake. In the meantime, try this link as a start. They sell bass boats.....among other things. NB

http://www.dougrussell.com/

EDIT: Maybe not. I may be thinking of a place just down the street from Doug Russell which i thought was an annex. I'll have a look and get back.

EDIT 2: Here is the place down the street from Doug Russell.

http://www.boats.com/sites/marineusa-worcester

EDIT 3: Try Google: "Bass Boat Dealers, Winnipesuakee, NH" I found a bunch.


Thanks. Marineusa in Worcester looks like they should be able to help me out. I was hoping for someone on Winnipesaukee, but I don't think there are any bass boat dealers.

I am using 2 12v batteries in series but it was all hooked up through the battery charger when I got the boat. There are taps for 12v and 24v outputs but both measure 12v. It sounds like I at least need a new charger...
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Old 06-02-2010, 06:14 PM   #6
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...also try Greenes marine in Hooksett.
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Old 06-02-2010, 09:10 PM   #7
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Try Dave Motorboat shop in Gilford, he always knows the answer or someone who does.
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Old 06-02-2010, 09:28 PM   #8
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Another person you might try, and I would suggest is Jason( Service manager ) at Irwins in lakeport. I've bought 2 different bass boats from them, Procraft, and a Skeeter, when they we're dealers of these boats. Jason is very,very clever in these matters. On 1 of my boats they had to replace the trolling motor, and I have never had a problem with it, and its been 5 years. His Number is 524-6661. Good luck !
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Old 06-02-2010, 10:07 PM   #9
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Question Some questions for you

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Originally Posted by Fish'n John View Post
I have a '98 Glastron "Fish and Ski". It has a 24V Min Kota 64lb trolling motor operated through a Dual Phase II on-board battery charger/bat. system interlink (not made any more). I imagine that this is a set-up like found on some Bass Boats. I can only get 12v output to the motor which is only useful if there is no wind. I have tried wiring it direct to 24v but I end up blowing fuses. I am at my wits end trying to figure out if the problem is in the charger, the trolling motor or the connections. I have tried Fays Boat Yard, who seem like good local experts, and they were little help on this issue. I have tried online to find a nearby shop that works on Bass Boats without success.

Does anyone have an idea where to turn for help?
I'm no expert either but perhaps I can help. When you say you can only get 12V to the motor, when is this happening ? I mean what are the connections between the batteries, the motor and the charger ? When you say you wired it direct what were the connections then and what fuses were blown ? What I'm wondering is IF you have to manually remove a jumper/connection between the 2 batteries when charging (so as to have only 12V) and replace it when trolling (so as to get 24V). I tried searching the WWW for info on your unit but didn't have much luck. About all I could find is that the parent company for your charger is thought to be GoldenEye (see last post there and if this sounds familar for wiring). Still ... how hard can it be ?


Note the warning on the diagram below. Perhaps your outputs are not isolated and the wire between the batt 2 + and the batt 1 - needs to be disconnected when charging. Then again perhaps it's just the connections that are not proper. See if the diagram makes sense to you and comment how close your system is to it.

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Old 06-03-2010, 06:18 AM   #10
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Originally Posted by Mee-n-Mac View Post
I'm no expert either but perhaps I can help. When you say you can only get 12V to the motor, when is this happening ? I mean what are the connections between the batteries, the motor and the charger ? When you say you wired it direct what were the connections then and what fuses were blown ? What I'm wondering is IF you have to manually remove a jumper/connection between the 2 batteries when charging (so as to have only 12V) and replace it when trolling (so as to get 24V). I tried searching the WWW for info on your unit but didn't have much luck. About all I could find is that the parent company for your charger is thought to be GoldenEye (see last post there and if this sounds familar for wiring). Still ... how hard can it be ?


Note the warning on the diagram below. Perhaps your outputs are not isolated and the wire between the batt 2 + and the batt 1 - needs to be disconnected when charging. Then again perhaps it's just the connections that are not proper. See if the diagram makes sense to you and comment how close your system is to it.

My system is pretty close to the drawing you posted. The Dual Phase II book says to remove the series connection between the 2 aux batteries. This was done. It also says their unit ..."is equipped with internal series/parallel switching. Therefore all other series connections must be removed or severe damage may result..." There are two output connections on the side of the charger, one for 12v and one for 24v. The 24v is hooked up to the trolling motor. When I noticed the trolling motor slowing down, I checked the voltage at these terminals. Both read 12v.

When I tried to hook the batteries up directly, I bypassed the charger as shown in your solid lines using the wires that were installed from the tr. motor to the charger. I smoked the wires and burned out a 30A fuse. I put in heavier wires (#8) and a 60A fuse. The motor ran at 24V until I melted the connection from my boat to the trolling motor. This told me that the motor was never set up properly and that I only had 12v from the start.

At this point I got a little gun shy and have been trying to get some professional help...
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Old 06-03-2010, 08:53 AM   #11
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The drawing above is for a 24 volt system. The output is 24 volts. There is no 12 volt output shown. Your decision to seek professional advice is a good one.

If your boat stays IN The Water at a dock with shore power, it is IMPERATIVE that the wiring in the boat be correct, or you risk "electrolysis" which will quite likely EAT up your outdrive, or outboard lower unit if it remains in contact/imersed in the water. This damage can actually happen over night (while plugged in to shore power) and will be seen as blistering and shedding of the paint on the lower unit. The aluminum under the paint actually disolves.

As an aside: This same result can occur if the Dock is incorrectly wired. NB
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Old 06-03-2010, 12:50 PM   #12
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Arrow May I suggest a few tests

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My system is pretty close to the drawing you posted. The Dual Phase II book says to remove the series connection between the 2 aux batteries. This was done. It also says their unit ..."is equipped with internal series/parallel switching. Therefore all other series connections must be removed or severe damage may result..." There are two output connections on the side of the charger, one for 12v and one for 24v. The 24v is hooked up to the trolling motor.
OK, it sounds like the charging system is putting the batts in parallel (neg to neg, pos to pos) to charge them (simultaneously) off a single 12V tap. Then when the charger isn't charging it connects them in series to make a 24V system. While I suspect NB is correct (you'll need to see a pro) let's try to do a little simple, non-destructive testing to see what's working and what's not.

To that end disconnect the trolling motor from the system, leaving the charger and batts as shown in the diagram (minus the jumper btw the batts, remove that per the instructions). That should give you 4 wires from the charger to the batts. With the charger off, measure the voltage (seems you know how to do this) between the neg on "batt 2" and the pos on the other batt. It should be 24V if my thinking above is correct. Turn the charger on and see if it's now 12V. Indeed a measurement from the neg of any batt to the pos of any batt should be 12V (again assuming I'm correct above). If the above works then the charger would seem to be doing it's job. My concern is that it might not be coming out of the "charge configuration".

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Originally Posted by Fish'n John View Post
When I noticed the trolling motor slowing down, I checked the voltage at these terminals. Both read 12v.
I assume you measured as above, from the neg of batt 1 (in the pic) to the pos of batt1 and then also to the pos of batt2 (from the neg of batt 1) ? I'm a little unsure of where to where you measured.

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When I tried to hook the batteries up directly, I bypassed the charger as shown in your solid lines using the wires that were installed from the tr. motor to the charger. I smoked the wires and burned out a 30A fuse. I put in heavier wires (#8) and a 60A fuse. The motor ran at 24V until I melted the connection from my boat to the trolling motor. This told me that the motor was never set up properly and that I only had 12v from the start.
I'm a little confused as to what you did. Did you remove the charger completely and have the batts connected to each other (re-install the jumper btw the batts) and the trolling motor (controller) as shown in the pic (solid lines = wires you had, no wires coresponding to the dashed lines) ? This certainly should have given your motor 24V, assuming the batts are good and the connections are good and the wires big enough for the current. On this latter point ... what wires were in the system when you got it ? Was this all working at some point in time ? The #8 wires should be OK, assuming they're not overly long as I'd expect your motor to draw less than 30A. Which leads me to suspect something isn't right in your motor/controller. It shouldn't have popped the 30A fuse nor melted anything (I'm assuming the motor plug/socket is really clean). I have a suspicion that your motor is somehow setup for 12V, not 24V, operation. Not to be too stupid but how sure are you that it's a 24V motor ? Is there any chance that the motor has a 12V option (ie - can it be wired to use 12V or 24V) ?

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Originally Posted by Fish'n John View Post
At this point I got a little gun shy and have been trying to get some professional help...
I don't blame you. I'd be a little concerned about popping 30A fuses and melting wires ! Still it's best the divide and conquer these type of problems. First make sure the batts are both good and not just at no load conditions. Make sure the connections are all clean and tight. Try to see if it's the charger or the motor that's the problem. It appears you've already thought along these lines ! If there's no other way to connect or configure the motor/controller (12 vs 24 V) then it's time to pay the pro.
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Old 06-04-2010, 12:12 PM   #13
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Quote:
To that end disconnect the trolling motor from the system, leaving the charger and batts as shown in the diagram (minus the jumper btw the batts, remove that per the instructions). That should give you 4 wires from the charger to the batts. With the charger off, measure the voltage (seems you know how to do this) between the neg on "batt 2" and the pos on the other batt. It should be 24V if my thinking above is correct. Turn the charger on and see if it's now 12V. Indeed a measurement from the neg of any batt to the pos of any batt should be 12V (again assuming I'm correct above). If the above works then the charger would seem to be doing it's job. My concern is that it might not be coming out of the "charge configuration".
With the trolling motor disconnected, jumper off (which indeed leaves 4 wires from the charger to the batteries) I measure no voltage measured either at the 24v terminals on the charger or between the batteries (from the positive on Bat 1 to the negative on Bat 2). If I turn the ignition switch to the "Accessory" position, I measure 12v at both locations. (I have noticed that at times I can keep the trolling motor running at 12v if I turn the ignition switch to this position???). I did not yet try turning the charger on, but it seems the internal series to parallel swith in the charger is not working.

Quote:
I assume you measured as above, from the neg of batt 1 (in the pic) to the pos of batt1 and then also to the pos of batt2 (from the neg of batt 1) ? I'm a little unsure of where to where you measured.
Actually, I was measuring the voltage at the output terminals on the charger. I didn't think to measure it right on the batteries.


Quote:
I'm a little confused as to what you did. Did you remove the charger completely and have the batts connected to each other (re-install the jumper btw the batts) and the trolling motor (controller) as shown in the pic (solid lines = wires you had, no wires coresponding to the dashed lines) ?
Yes, this is exactly how I wired it. Initially I used the wires that were initially hooked up from the charger to the motor. They were #12 or #14 wires and smoked like hell when I first put 24v to them. I also blew the 30A fuse they had in line.

Quote:
This certainly should have given your motor 24V, assuming the batts are good and the connections are good and the wires big enough for the current. On this latter point ... what wires were in the system when you got it ? Was this all working at some point in time ? The #8 wires should be OK, assuming they're not overly long as I'd expect your motor to draw less than 30A. Which leads me to suspect something isn't right in your motor/controller. It shouldn't have popped the 30A fuse nor melted anything (I'm assuming the motor plug/socket is really clean). I have a suspicion that your motor is somehow setup for 12V, not 24V, operation. Not to be too stupid but how sure are you that it's a 24V motor ? Is there any chance that the motor has a 12V option (ie - can it be wired to use 12V or 24V) ?
I checked the Minn Kota book that came with the 64lb thrust motor. It will work at either 12 or 24v. They recommend #8 wires and 60A fuses at 24v. I installed new wires and fuses but used the existing plugin connection on the front boat panel. When I wired the motor directly to 24v, it worked fine but stopped after awhile. I found I had melted the plugin connection. I don't think the motor was ever set up for 24V. I bought the boat new with a 12v Minn Kota installed by the dealer. It was too weak so I bought a new 24V motor and took it into the dealer (Expo North, Rt 16). They supposedly rewired it for me, but I think now that they just hooked it up with the old wiring. I guess the new motor at 12v was better than the first one and I never noticed that I wasn't getting full performance.



Quote:
I don't blame you. I'd be a little concerned about popping 30A fuses and melting wires ! Still it's best the divide and conquer these type of problems. First make sure the batts are both good and not just at no load conditions. Make sure the connections are all clean and tight. Try to see if it's the charger or the motor that's the problem. It appears you've already thought along these lines ! If there's no other way to connect or configure the motor/controller (12 vs 24 V) then it's time to pay the pro.
The batteries are both good. I had them checked under load and replaced one late last year. The connections are all clean and tight. I think it is clear that the charger is not working at 24v but the one question that keeps nagging at me is why it didn't output 24v as it first came back from Expo North. Could they have rewired the charger for 12v at each set of terminals?? Certainly if it had worked right in 1998 they would have burned up the existing wiring if they had run it the way it "appears" to be hooked up. I think I have to pull that battery charger for a look inside before I take it anywhere. What do you think?
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Old 06-07-2010, 02:20 PM   #14
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Arrow Curiouser and curiouser

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The batteries are both good. I had them checked under load and replaced one late last year. The connections are all clean and tight. I think it is clear that the charger is not working at 24v but the one question that keeps nagging at me is why it didn't output 24v as it first came back from Expo North. Could they have rewired the charger for 12v at each set of terminals?? Certainly if it had worked right in 1998 they would have burned up the existing wiring if they had run it the way it "appears" to be hooked up. I think I have to pull that battery charger for a look inside before I take it anywhere. What do you think?
I agree, it sounds like they wired it for a 12V motor and that's the only way it's been operated all this time (new trolling motor [TM] being better than old TM even at 12V). As for the ignition SW being in the accessory position ... I read a thread that said the charger had another set of wires to the main, boat battery and that when the ignition was on, it would parallel all the batts so as to charge them up off the engine's alternator. I'm not sure how well this would work but it sounds like the charger is breaking the series connection btw the batts and paralleling them when the ignition sw is in the accessory position. I'll guess this is proper for the moment. Now as to why you get zero volts ... at first glance it seems there's only 2 possibilities : the charger is broken (not making the series connection) or the terminals are mislabeled.

On the latter ... pretend due to a mislabelling you connected the batts with the 2 pos terminals tied together when trolling (via the internal series connection). Then if you measured (on the charger) btw the neg and 24V output you'd see +12 added to -12V (minus voltage due to the batt reversal) and get 0 volts out. This would mean you'd never be able to run the motor off the batts though and at some point it did work if only in "12v mode". Moreover when the batts are in paralleled to charge, you'd have the 12V reversed going to the mislabelled battery and that, absent any internal protection in the charger, would be a very bad thing indeed. This possibility sounds like it's ruled out then.

Thus I agree it sounds like the charger isn't making the serial connection when it should. But if this is the case, then with only 2 wires going to the TM from the batts/charger, then there would be no voltage due the missing serial connection. Again at some point both TMs ran, if only at some lesser voltage perhaps. So I'm beginning to think you have a wiring issue and a maybe a half working charger. Did you notice how it was wired when it came from Expo North ? I'll guess (again) perhaps they had it wired somehow for 12V operation only.

I agree that #14 wire is insufficient to run any TM off of, so the wires burning up (at 60A) isn't a surprise ... though ... if the charger is supposed to make the series connection btw the batts, then the wires (2 of the 4 to be exact) connecting the charger to the batts would be carrying the full current through them. AWG12 might just work for a small run but I wouldn't trust it so I doubt the charger designer would have either (at 60A). The rule I read is 1A for each lb of thrust at 12V, half that at 24V. But let's take your TM's book at face value and say it's supposed to draw 60A. Hence the smoked wires. The AWG8 should have been OK but the melted connector is troubling. Unless it was corroded and making a "high" loss connection, then the melting at 60A would be understandable. I get the gut feeling there's something I'm missing here ...

The way the old systems worked was to deliver 24V to the TM. If you wanted less than full speed, the TM controller added resistance in series with the motor, thus decreasing the current draw and also reducing the voltage seen by the actual motor itself. If you kept reducing the speed, increasing the resistance, at some point the motor would have less than 12V across it. So the old 12/24 systems would switch out the series resistance and 24V, and connect 12V, perhaps through a lesser series resistance, to the motor. It saved the battery this way and allowed a finer low speed control. The question for you is where this switching is taking place, if indeed it is at all. Newer TMs come with pulse width modulation (PWM) speed control and don't have any voltage switching. I do worry that your old charger might not be rated to handle the newer motors current. May I assume it came with 30A fuse ? That the new(er) TM came with the 60A fuse but that it wasn't installed when you brought it to Expo North ?

What other wires come out of the charger to ... well, any place ? What are the labels on the wires ... or terminals on the charger ?
How many wires run to the TM controller; 2, 3 or 4 ? What gauge would you guess they are ? What MK TM do you have ?
Lastly I'd think the series/parallel connection internal to the charger would be made by a fairly hefty relay or solenoid. Can you hear a good click or clunk when the ignition switch is turned from off to accessory (or on) ? Or going back the other way, accessory to off ?

If you feel inclined and have some electrical saavy, take the charger inside. It sounds like you have a complete manual for it. I'm not sure how well trouble shooting over the forum will work but you've got my curiousity aroused now.

Here's my guess at how the system should work. When AC power is off and the ignition is off, the relay switch goes to it's unpowered state and the batts are connected in series (internal to the charger) and you should see 24V across the proper terminals (assuming the right connections to the batts). This voltage should go to the TM on 2 hefty wires (AWG6 or 8). The TM then works off the 24V as it's designed to. When the AC is on or when the ignition is on (really shouldn't be accessory but ...) the relay switch is energized, the series connection is broken and the parallel conenction is made. I'm assuming there's another pair of wires to another battery (the main boat batt) that you haven't mentioned. The TM batts are then charged off the AC/DC converter or from the engines alternator. The voltage at the 24V output would then also be 12V, same as across all the + to - battery terminals. The charger should have 2 current "ratings"; one at which the batts are charged (perhaps 5 - 10 amps) and a max current when the TM is being run. Ideally the TM connections are made to the batteries themselves and not to the charger terminals. If it's done at the charger then all the wires from the charger to the TM batts need to be "hefty".

FWIW here's a nice chart and online calculator for what wire size is needed and how much voltage drop can be expected for a given current draw and AWG ... http://www.powerstream.com/Wire_Size.htm

Here's a simplified diagram of the wiring paths in each mode; when trolling or when charging. Note the fat lines indicating where the max current is supposed to flow.
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Old 06-08-2010, 08:53 AM   #15
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Here are my answers to your specific points:

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Quote:
As for the ignition SW being in the accessory position ... I read a thread that said the charger had another set of wires to the main, boat battery and that when the ignition was on, it would parallel all the batts so as to charge them up off the engine's alternator. I'm not sure how well this would work but it sounds like the charger is breaking the series connection btw the batts and paralleling them when the ignition sw is in the accessory position.
This is right. The manual says the charger is connected to the ignition switch so that it is "on" when the ignition switch is on. It says this allows the batteries to charge while the boat is running.

Quote:
Now as to why you get zero volts ... at first glance it seems there's only 2 possibilities : the charger is broken (not making the series connection) or the terminals are mislabeled.
I wonder if this connection to the ignition also may answer why I get 0V when the ignition switch is off. Since the jumper connection is only made inside the charger, the charger has to be on or I have an open circuit between the two 12v batteries. It seems to make sense to me that with the charger off I should get 0v at both locations. What I don't understand is why I get 12v when the ignition switch is on. Maybe the charger is wired internally so the 24v terminal is looking only at one 12v battery, but does it make sense to you that measured across batteries 1 and 2 with no jumper I should get 12v?

Quote:
Thus I agree it sounds like the charger isn't making the serial connection when it should. But if this is the case, then with only 2 wires going to the TM from the batts/charger, then there would be no voltage due the missing serial connection. Again at some point both TMs ran, if only at some lesser voltage perhaps. So I'm beginning to think you have a wiring issue and a maybe a half working charger. Did you notice how it was wired when it came from Expo North ? I'll guess (again) perhaps they had it wired somehow for 12V operation only.
Actually, there are 4 wires going from the charger to the TM. This is just how it was wired originally and how it is hooked up now. The only difference now is that I have installed #8 wires and 60a fuses. Two wires come from the 12v terminals and 2 wires come from the 24v terminals. The only time it was wired with only 2 wires was when I connected the 24v directly to the TM directly. I never have understood why those 12v wires are there. I thought maybe the motor that runs the positioning ran at 12v, but I see in the manual that this motor should run with only a single 24v connection, if I understand the drawing. The motors apparently both still work at 12v only more slowly.

I agree that #14 wire is insufficient to run any TM off of, so the wires burning up (at 60A) isn't a surprise ... though ... if the charger is supposed to make the series connection btw the batts, then the wires (2 of the 4 to be exact) connecting the charger to the batts would be carrying the full current through them. AWG12 might just work for a small run but I wouldn't trust it so I doubt the charger designer would have either (at 60A). The rule I read is 1A for each lb of thrust at 12V, half that at 24V. But let's take your TM's book at face value and say it's supposed to draw 60A. Hence the smoked wires. The AWG8 should have been OK but the melted connector is troubling. Unless it was corroded and making a "high" loss connection, then the melting at 60A would be understandable. I get the gut feeling there's something I'm missing here ...

Quote:
The way the old systems worked was to deliver 24V to the TM. If you wanted less than full speed, the TM controller added resistance in series with the motor, thus decreasing the current draw and also reducing the voltage seen by the actual motor itself. If you kept reducing the speed, increasing the resistance, at some point the motor would have less than 12V across it. So the old 12/24 systems would switch out the series resistance and 24V, and connect 12V, perhaps through a lesser series resistance, to the motor. It saved the battery this way and allowed a finer low speed control. The question for you is where this switching is taking place, if indeed it is at all. Newer TMs come with pulse width modulation (PWM) speed control and don't have any voltage switching. I do worry that your old charger might not be rated to handle the newer motors current. May I assume it came with 30A fuse ? That the new(er) TM came with the 60A fuse but that it wasn't installed when you brought it to Expo North ?
The Minn Kota manual talks about pulse width modulation to extend battery life. Neirther the Minn Kota or the Dual Phase II manuals discuss amperage. The Minn Kota motors now all are sold with a warning to protect them with a 60A reseatable safety. I think this is where I got the 60A number.

Quote:
What other wires come out of the charger to ... well, any place ? What are the labels on the wires ... or terminals on the charger ?
How many wires run to the TM controller; 2, 3 or 4 ? What gauge would you guess they are ? What MK TM do you have ?
There are 4 output wires going to the TM control (2 at 12v and 2 at 24v), a power cord, a red wire to the ignition switch, three sets of leads to the 3 batteries (main, aux 1 & aux 2) and a "sense wire" that goes to the pos terminal on Aux 2 battery. The wires going to the TM control now are #8 with 60a fuses. The trolling motor is a Minn Kota Bowmount Powerdrive Autopilot with a 60" shaft and 64ib thrust for operation at 24v.

Quote:
Lastly I'd think the series/parallel connection internal to the charger would be made by a fairly hefty relay or solenoid. Can you hear a good click or clunk when the ignition switch is turned from off to accessory (or on) ? Or going back the other way, accessory to off ?
Yes, I could never figure out what it was before, but when I put the switch into the accessory position there is a windup and a click sound. I must have the engine compartment open and it has to be quiet, but I heard it this morning. It is definitely coming from the area of the charger.

Quote:
If you feel inclined and have some electrical saavy, take the charger inside. It sounds like you have a complete manual for it. I'm not sure how well trouble shooting over the forum will work but you've got my curiousity aroused now.
I'll try it.

Quote:
Here's my guess at how the system should work. When AC power is off and the ignition is off, the relay switch goes to it's unpowered state and the batts are connected in series (internal to the charger) and you should see 24V across the proper terminals (assuming the right connections to the batts). This voltage should go to the TM on 2 hefty wires (AWG6 or 8). The TM then works off the 24V as it's designed to. When the AC is on or when the ignition is on (really shouldn't be accessory but ...) the relay switch is energized, the series connection is broken and the parallel conenction is made. I'm assuming there's another pair of wires to another battery (the main boat batt) that you haven't mentioned. The TM batts are then charged off the AC/DC converter or from the engines alternator. The voltage at the 24V output would then also be 12V, same as across all the + to - battery terminals. The charger should have 2 current "ratings"; one at which the batts are charged (perhaps 5 - 10 amps) and a max current when the TM is being run. Ideally the TM connections are made to the batteries themselves and not to the charger terminals. If it's done at the charger then all the wires from the charger to the TM batts need to be "hefty".
I'll have to think about this some more. I can't get past the thought that the voltage at the 24v taps on the charger were 0v until I put the ignition switch into the accessory position. Then I got 12v...?

Here's a simplified diagram of the wiring paths in each mode; when trolling or when charging. Note the fat lines indicating where the max current is supposed to flow.
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Old 06-08-2010, 06:35 PM   #16
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I wonder if this connection to the ignition also may answer why I get 0V when the ignition switch is off. Since the jumper connection is only made inside the charger, the charger has to be on or I have an open circuit between the two 12v batteries. It seems to make sense to me that with the charger off I should get 0v at both locations. What I don't understand is why I get 12v when the ignition switch is on. Maybe the charger is wired internally so the 24v terminal is looking only at one 12v battery, but does it make sense to you that measured across batteries 1 and 2 with no jumper I should get 12v?
I think what you've measured makes some sense but it's the opposite of what I think you've said above. What happens (IMO) when the ignition is on or when the charger is plugged into the AC outlet is that the charger configures itself in what I've called "charge mode". The (internal) series connection between the 2 trolling batts is opened and then all the batts, including the engine batt, are connected in parallel (+to+, -to-) and then also connected to the engines alternator output or the chargers AC/DC output. This charges (or tries to) all the batts simultaneously. Thus I'd expect you'd measure 12V at all the outputs when the ignition is on or the charger is on AC. There is no series connection between the batts to add them to make any higher voltage in this "charge mode".

Now with the AC off and the ignition off (like you'd have when trolling) the charger should reconfigure itself. The trolling batts should be isolated from the engine batt and the (internal) series connection between the 2 trolling batts should now be made. Thus the voltage across these 2 batteries adds up to the desired 24V. This last part doesn't seem to be happening. It appears the charger is coming out of "charge mode" but not fully going into "trolling mode". What's missing is that internal series connection. Thus when you measure from the 24V + terminal to the 24V - terminal you get zero volts. The circuit is open. It's the same as trying to measure the voltage between 2 AA batteries sitting on your table by putting one lead of the volt meter on one batteries - and the other lead on the other batteries +, w/o any other connection between the 2 batts. Now the question is why is this the case. If the clunk you hear is the charger solenoid trying to make it's internal serial connection then either a wire has come off, burned up ... or was taken off deliberately. Let me explain the last part.

When you had your old 12V TM, the installer might have disabled the 24V output so you couldn't blow up your TM by giving it 24V (disconnected a wire inside of the charger so even when the relay engaged it wouldn't make the serial connection to add the batts). When the new TM was added the guys at Expo North might just have kept the old wiring ... just because they didn't realize it could be changed. Thus you've been deprived all these years, running at half thrust. If this theory is correct then you might be able to open up the charger and replace the missing connection and get your 24V back. However there are multiple other things that could be wrong. Before I can troubleshoot any further I need to understand what the connections are.

See my new diagram and see if you agree with the labels and connections to the batteries. I've shown it with the internal connections as I think they should be when the charger is operating in "trolling mode". I could have the Aux1 and Aux2 labels swapped so before we go any further perhaps you could make a few voltage measurements and settle the diagram.

With the AC not connected, the ignition switch off and all the batteries connected and the TM completely disconnected ...

Measure the voltage between Aux1 + and Aux1 -. It better be +12V. This confirms the battery is connected.

Measure the voltage between Aux2 + and Aux2 -. It better be +12V. This confirms that battery is connected. Now it gets fun.

Measure the voltage between Aux2 + and Aux1 -. I hope it's +24V. This confirms the batteries are connected in series and my labels Aux1 and 2 are proper. If it's 0 V then there's more possibilities.

Measure the voltage between Aux2 - and Aux1 +. If the above measurement was +24V then this should be 0 V. If the above measurement was 0 V then this might be -24 V. This means I've swapped the labels/meaning of Aux 1 and 2. No problemo as it still indicates the desired serial connection is being made. If it's 0 V and the above measurement was also 0 V then I can't tell much about my Aux1 and 2 labels but I'm sure the series connection isn't being made (for some reason).

BTW it's real important that the volt meter be connected "properly" to make each of the above measuements. Otherwise you'll measure - voltage when it's really + voltage. By "proper" I mean that when I say measure between "A" and "B", you put the + probe of the volt meter on "A" and the - probe of the volt meter on "B". This will be obvious when measuring across a battery. + probe on the + post and - probe on - post should get you +12V and not -12V.

Now if you're still up for more fun we can see if there's nothing missing in the other internal wiring. With the + probe of the voltmeter on "Aux1 +" terminal, put the - probe on the 12V - terminal. I hope you read +12V. If not I've probably got my Aux 1 and 2 labels swapped. If I do then stop and I'll see what makes sense to do next. If you do read +12V then continue and put the - probe on the 24V - terminal (leaving the + probe of the voltmeter on Aux1 + terminal). Again I hope to see +12V. Finally measure between the 24V + terminal and the Aux1 - terminal. I'd hope for +24V but given your prior measurements I think it'll be 0 V, same as I might expect for the above "between Aux2 + and Aux1 -" measurement. Given these results we can determine what labels are what and what's missing (if anything) for internal charger connections. See how "fun" this is ?
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Old 06-09-2010, 08:46 AM   #17
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Here's my guess at how the system should work. When AC power is off and the ignition is off, the relay switch goes to it's unpowered state and the batts are connected in series (internal to the charger) and you should see 24V across the proper terminals (assuming the right connections to the batts). This voltage should go to the TM on 2 hefty wires (AWG6 or 8). The TM then works off the 24V as it's designed to. When the AC is on or when the ignition is on (really shouldn't be accessory but ...) the relay switch is energized, the series connection is broken and the parallel conenction is made. I'm assuming there's another pair of wires to another battery (the main boat batt) that you haven't mentioned. The TM batts are then charged off the AC/DC converter or from the engines alternator. The voltage at the 24V output would then also be 12V, same as across all the + to - battery terminals. The charger should have 2 current "ratings"; one at which the batts are charged (perhaps 5 - 10 amps) and a max current when the TM is being run. Ideally the TM connections are made to the batteries themselves and not to the charger terminals. If it's done at the charger then all the wires from the charger to the TM batts need to be "hefty".

FWIW here's a nice chart and online calculator for what wire size is needed and how much voltage drop can be expected for a given current draw and AWG ... http://www.powerstream.com/Wire_Size.htm

Here's a simplified diagram of the wiring paths in each mode; when trolling or when charging. Note the fat lines indicating where the max current is supposed to flow.
OK. I have finally digested your drawing and comments on how the system should work. I agree and now understand why I registered 12v at both the 24v output lugs on charger and at the batteries after turning the ignition switch to the accessory position. The 0V readings with power off must mean some malfunction in the charger and I am preparing my mind to remove the charger from the boat for a look inside. It takes time to get my aging body into a position to remove this from the very back of a small engine compartment. Meantime I'll try to attach some drawings from my manuals. If it works, I'll attach others.
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Old 06-09-2010, 09:09 AM   #18
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Default More charger & TM diagrams

Here are a few more relevant pages of the manuals.
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File Type: pdf Tr Motor (2).pdf (1.18 MB, 621 views)
File Type: pdf Dual Phase II (5).pdf (1.40 MB, 649 views)
File Type: pdf Dual Phase II (6).pdf (1.37 MB, 666 views)
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Old 06-09-2010, 12:53 PM   #19
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OK. I have finally digested your drawing and comments on how the system should work. I agree and now understand why I registered 12v at both the 24v output lugs on charger and at the batteries after turning the ignition switch to the accessory position. The 0V readings with power off must mean some malfunction in the charger and I am preparing my mind to remove the charger from the boat for a look inside. It takes time to get my aging body into a position to remove this from the very back of a small engine compartment. Meantime I'll try to attach some drawings from my manuals. If it works, I'll attach others.
Excellent, it worked ! I briefly glanced at the attachments and it appears my simple diagram had/has the Aux1 and Aux2 connections correct. That is, the Aux2+ should be at +24V when trolling. So my prior troubleshooting measurements should tell us what's good and what's bad in the charger. I am curious as to what indicator lights are available and what they mean. It could be that "sense" line lights up an indicator light to tell you that 24V is available. It seems "odd" to me they would use a seperate wire given they already have on going to that battery post. Minor mystery I s'pose.

In any case we're just a little bit away from knowing what to do with the charger and now I want to understand what happened when you disconnected the charger and wired up the TM to the batts for 24V operation. That looks to have be correctly done. The TM worked (and I assume well) until the plug melted. So that seems like a bad plug or very lossy connections at the plug. Plugs have current ratings, do you know what this one was rated for ? In any case it's time for a new plug and socket. Get ones rated for the proper current (60A) and when the charger issues are settled, I think you'll be good to go.
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Old 06-10-2010, 09:25 AM   #20
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In any case we're just a little bit away from knowing what to do with the charger and now I want to understand what happened when you disconnected the charger and wired up the TM to the batts for 24V operation. That looks to have be correctly done. The TM worked (and I assume well) until the plug melted. So that seems like a bad plug or very lossy connections at the plug. Plugs have current ratings, do you know what this one was rated for ? In any case it's time for a new plug and socket. Get ones rated for the proper current (60A) and when the charger issues are settled, I think you'll be good to go.
Yes, The trolling motor ran well when I direct wired it at 24V. When the plug melted, I got nervous and backed off. I fixed the plug with spares I had from the original installation but I rewired everything through the charger and yelled for help. Now I see that the charger is a problem.

Just this morning I was looking through my West Marine catalog and I noticed that these connectors have ratings of 12v or 24v and designated wire sizes of #8 or #10. At this point I have to assume that I had 12v connectors and #10 wire size. Connections may also have been a little dirty. I just ordered two new TM connectors from West Marine at 24v and #8wire. Anyway, I will switch out these connectors when they arrive and I think I should be good to go. I should be able to wire the TM direct with the existing #8 wires and 60A fuses. I will also pull the battery charger and have a look inside and see if it is salvageable. If not, I should be able to replace it with a new and more conventional unit.

I really appreciate your help in all this. I'll let you know how I make out.
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Old 06-10-2010, 09:43 AM   #21
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Default Indicator Lights

Here are a few more pages of the manuals just for grins.

You asked about the indicator lights. That is shown on (7). The charger actually sequences the charging of the batteries so that the main is recharged first, then the auxillaries. The sequence is shown in the light patterns. I don't know what the sense wire is for...
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File Type: pdf Dual Phase II (7).pdf (872.1 KB, 561 views)
File Type: pdf Dual Phase II.pdf (503.9 KB, 585 views)
File Type: pdf Dual Phase II (2).pdf (824.7 KB, 696 views)
File Type: pdf Tr Motor.pdf (387.4 KB, 494 views)
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Old 06-14-2010, 10:25 AM   #22
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I have removed and inspected the battery charger. There are no internal fuses that I recognize and no places where the original wiring seems to have been altered. The only abnormality that I notice is some apparent heat damage to the wire that leads in from Aux battery #2. The black negative wire appears to have been overheated at the spot where it is connected to a one of three 1" x 1" x 1" components. They are black with a white top with a number (951221B) inscribed on the side. There is a second heavy black wire leading from this component to a black device that also appears to be heat damaged. This device has an enscription "Short Stop", and below that "12v A46 4OR". None of this means anything to me, and since the company is out of business, I assume I need a new charger.

I have rewired the batteries direct to the trolling motor using #8 wire and 60a fuses as much as I can. I am waiting for the 24v #8 connector for the TM before I can try this system out with direct wiring...
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Old 06-15-2010, 03:33 PM   #23
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I have removed and inspected the battery charger. There are no internal fuses that I recognize and no places where the original wiring seems to have been altered. The only abnormality that I notice is some apparent heat damage to the wire that leads in from Aux battery #2. The black negative wire appears to have been overheated at the spot where it is connected to a one of three 1" x 1" x 1" components. They are black with a white top with a number (951221B) inscribed on the side. There is a second heavy black wire leading from this component to a black device that also appears to be heat damaged. This device has an enscription "Short Stop", and below that "12v A46 4OR". None of this means anything to me, and since the company is out of business, I assume I need a new charger.

I have rewired the batteries direct to the trolling motor using #8 wire and 60a fuses as much as I can. I am waiting for the 24v #8 connector for the TM before I can try this system out with direct wiring...

Hmmm, I'll offer up this sage guess ... it's dead.


It might be repairable but w/o any schematics or even a parts list that'll probably cost more than a newer, betterer charger. I might hazard a SWAG that the "short stop" device is some sort of fuse or circuit breaker made for 12v and 46A. Or perhaps it's the switch to go from 12V to 24V configuration ? In any case the negative lead for the Aux2 battery would carry the full current when in 24V mode which, according to your TM manual, might be as much as 48A (0.75A/lb x 64 lbs). Maybe the "new" TM was more than the "old" charger could handle ? If you care to post a pic of the charred devices I'll have a look but I'll guess parts are now obsolete.

As for your 24V connector ... I looked briefly at the connectors/plugs in the WM catalog. I couldn't imagine why there would be 12V and 24V connectors, there's just not enough difference in voltage to make a difference in design. What I did see were 2 wires (+ and -) for the 12V sets and 3 wires (+24V, +12V and -) for the 24V ones. If you got one of these you'll end up using only 2 of the wires/contacts. If at all possible I would recommend getting a plug/socket set with 4 contacts (I didn't see one but I didn't look all that hard) and using 2 of the contacts (in parallel) for the +24V and the other 2 (in parallel) for the -. Indeed if you wanted to double up the AWG8 wires (for the longest run) that would be prefered as well. Somewhere I read than ideally the voltage drop in the wiring and connectors from the batts to the TM head should be <1v. I think the online calculator I previously listed estimates you'll have something more (1.3v) for a single AWG8 to and from batts carrying 50A and at what I guessed to be 20 away (40' round trip). I didn't see any current ratings on any of the plugs/sockets, which surprised me a bit.
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Old 06-15-2010, 06:54 PM   #24
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I couldn't imagine why there would be 12V and 24V connectors, there's just not enough difference in voltage to make a difference in design. current ratings on any of the plugs/sockets, which surprised me a bit.
I seem to remember a simple electrical principle from my studies some 40 years ago. This principle still works today as far as I know. If you raise the voltage in a supply line (Picture the overhead lines you see supplying power to the GRID).....you can REDUCE the amperage....which allows you to REDUCE the WIRE SIZE..therefore lighter weight...and still have the same power at the end of the line. Correct me if I'm wrong.......

This seems to me to be the case with this Trolling Motor. Having lighter wire seems to be a good thing...NO..?? NB
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Old 06-15-2010, 10:51 PM   #25
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I seem to remember a simple electrical principle from my studies some 40 years ago. This principle still works today as far as I know. If you raise the voltage in a supply line (Picture the overhead lines you see supplying power to the GRID).....you can REDUCE the amperage....which allows you to REDUCE the WIRE SIZE..therefore lighter weight...and still have the same power at the end of the line. Correct me if I'm wrong.......

This seems to me to be the case with this Trolling Motor. Having lighter wire seems to be a good thing...NO..?? NB

You are correct vis-a-vis supplying power like over the electric grid. IF the power is constant, a higher voltage reduces the current supplied. Of course there's some limits on how high the voltage can go ... but you remember correctly. In the case of trolling motors what's happened is that over time more powerful motors were wanted (boats got bigger and heavier I guess). This lead to very high currents and large wires at the old 12V standard. At some point they couldn't make a more powerful 12V motor and so 24V and 36V systems were designed.

In this case the TM manual says to expect a current = to 0.75 times the thrust. At 64 lbs this gets the OP about 48A current draw. With the wires he has this should be safe but he'll "lose" something like 1.3+ V in the wiring so IF he had exactly 24V at the battery terminals, he'd have 22.7V at the TM itself. I think the manual wanted the voltage loss to be 1V or less. The way to do this is with thicker (AWG) wires or more wires (of the same size). Doubling up on his AWG8 wiring would give the equivalent of using AWG5 wiring. That's a bit better then the AWG6 recommended at the fishing sites I looked at. It's more $$ but you get slightly better motor performance and more reliability. Then again how often will F'n'J be running his TM at full power ?
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Old 06-16-2010, 06:31 AM   #26
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The current only goes down if the load is a constant power. The national grid delivers a fixed number of watts, so if they use higher voltages in the transmission lines the current goes down. But most loads consumers are familiar with are not constant power. With a resistive load as you increase the voltage the current goes up. Switching power supply loads (like in a computer) are more or less constant power so if you increase the voltage the input current goes dow.
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Old 06-16-2010, 08:20 AM   #27
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In the case of AC,20 amps @ 120 volts equals 10 amps @ 240 volts.
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Old 06-17-2010, 10:03 AM   #28
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Last night I completed the wiring of the trolling motor direct from the batteries using the new 24v #8 connector in the bow panel. Rain kept me from trying it last night, but I was out early this morning and the Trolling motor is performing beautifully with no evidence of overheating in any wires or connectors. Even the Minn Kota on-board battery charge indicator and the Auto-pilot performed flawlessly. I have plenty of power to spare for even windy days. I am deliriously happy!

I will search for a more conventional on-board battery charger at my leisure, having relegated the failed Dual Phase II to the junk heap. Unanswered is how Expo North could have wired the unit as it was for 24v operation and how it could have worked at any level for as long as it did.

I am very grateful for the suggestions I received from all on The Forum, but especially to Mee-N-Mac for his hard work, inciteful analysis and probing questions. I could not have fixed the problem without your help.
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Mee-n-Mac (06-17-2010)
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