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Minn Kota 12V or 24V
I wonder if anybody can help me on this...
Which type of Minn Kota Transom-Mount should I choose for the following boat: 440 pounds, 14.5 feets I am thinking of a Vector or a Maxxum model. Do I need a 24V or a 12V motor? I will buy probably anyway two batteries. I have read that the 24V needs less Ampere. Will the 24V model run as long as the 12V model, longer or less longer? How long will it run approximately anyway? Thanks for any advice! Markus |
I have used my 30 lb Minnkota on various boats all around 16'. It is the 12
volt Endura model. With a single deep-cycle battery, it pushes them close to 4 mph for close to three hours. This will also depend strongly on the actual amp-hour rating of the battery. The higher the amp-hour rating, the longer. The more advanced motors with pulse width modulation controllers would run considerably longer at lower power settings. Theoretically there is no difference in longevity or power just based on voltage. However, in practice there is slightly less voltage drop on any connecting cables and the internal windings with the 24 volt set up meaning that slightly more of the energy stored in the battery reaches the motor. BS "Markus Fischer" wrote in message om... I wonder if anybody can help me on this... Which type of Minn Kota Transom-Mount should I choose for the following boat: 440 pounds, 14.5 feets I am thinking of a Vector or a Maxxum model. Do I need a 24V or a 12V motor? I will buy probably anyway two batteries. I have read that the 24V needs less Ampere. Will the 24V model run as long as the 12V model, longer or less longer? How long will it run approximately anyway? Thanks for any advice! Markus |
From an automotive view I'd stay with 12 myself. 24 will deliver a bit more power for amp use wich is a bit more eficient, however, the supporting of that voltage is a bit more critical. 24 volt battery chargers arn't cheap, and if you were going to charge the 24 v battery pac you would either need an external charger, or use a 24 v. alternator/generator,which again is higher cost. Plus, with a 12v motor eventually like all brush motors the brush's will wear down with a normal usage. With the 12 v. motor, the brush's can be replaced and usually the rest of the motor parts (armature) will be reusable. On a 24v motor the brush's will wear down faster because they are made of a softer material than the 12v sets, and when they get so short, the voltage is higher, and the carbon brush's will litterally arc and burn holes inthe armature. which would require not only a brush set, but also the brush holder assembly and an armature. in other words...the motor is fried, and you would porobably be better off buying a new motor. Like I said, this is my view, but I'd stick with the 12v. system. Tim |
Tim wrote:
From an automotive view I'd stay with 12 myself. 24 will deliver a bit more power for amp use wich is a bit more eficient, however, the supporting of that voltage is a bit more critical. 24 volt battery chargers arn't cheap, and if you were going to charge the 24 v battery pac you would either need an external charger, or use a 24 v. alternator/generator,which again is higher cost. Plus, with a 12v motor eventually like all brush motors the brush's will wear down with a normal usage. With the 12 v. motor, the brush's can be replaced and usually the rest of the motor parts (armature) will be reusable. On a 24v motor the brush's will wear down faster because they are made of a softer material than the 12v sets, and when they get so short, the voltage is higher, and the carbon brush's will litterally arc and burn holes inthe armature. which would require not only a brush set, but also the brush holder assembly and an armature. in other words...the motor is fried, and you would porobably be better off buying a new motor. Like I said, this is my view, but I'd stick with the 12v. system. Tim Last night I saw a 55 lb thrust 12 v Minn Kota at Costco for $ 359.00 CDN. that should move the boat along in sensible conditions. |
What the motor needs is Watts. W=V x A.
So to get the same power with 24V you need half the Amps you would need from a 12V battery. How long it runs depends on the Ah the battery delivers and the A the motor needs. But with the same weight batteries and same powerful motor there is no difference if you use 24 or 12 V Matt |
How long it runs depends on the Ah the battery delivers and the A the
motor needs. But with the same weight batteries and same powerful motor there is no difference if you use 24 or 12 V Matt Matt, for the most part I do agree with you. Usually, a 24v set up is wound for the higher voltage, and will be a slight bit more efficient on the wattage usage,then the 12v applications But in this type of application, I ageee that the benefit wouldn't even come close to weighing against the aformentioned disadvantages and costs. Tim |
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Shortwave Sportfishing writes:
If you are going to buy two batteries, connect them in parallel. Not a good idee. |
"Richard J Kinch" wrote in message . .. Shortwave Sportfishing writes: If you are going to buy two batteries, connect them in parallel. Not a good idee. Why? Hundreds of thousands of batteries are connected in parallel. Lots of critical energy systems have them in parallel as well as most large boats house banks. |
Bill McKee wrote: "Richard J Kinch" wrote in message . .. Shortwave Sportfishing writes: If you are going to buy two batteries, connect them in parallel. Not a good idee. Why? Hundreds of thousands of batteries are connected in parallel. Lots of critical energy systems have them in parallel as well as most large boats house banks. |
Thanks anybody for the inputs!
I am hesitating between a boat weighting 440 pounds and a very nice one weighting around 1000 pounds. Will a 12V 55 lb motor with two batteries (in parallel?) do the job still as fine? |
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On Tue, 26 Apr 2005 20:16:53 -0500, Richard J Kinch
wrote: Shortwave Sportfishing writes: If you are going to buy two batteries, connect them in parallel. Not a good idee. Really? Why? Later, Tom |
wrote in message ups.com... Thanks anybody for the inputs! I am hesitating between a boat weighting 440 pounds and a very nice one weighting around 1000 pounds. Will a 12V 55 lb motor with two batteries (in parallel?) do the job still as fine? I have two 12 volt batts hooked up in parallel for my 12 volt trolling motor. Works fine, and I get lots of time on the trolling motor. I think my boat weighs a little more than yours. |
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I have a 3200# boat and a MK 65# autopilot does fine. Even got me back to
the ramp last year when I ran out of gas 2 miles from the ramp. After 3 days and 100+ miles on the lake, you should look at the gas gage before the last 6 miles. Bill ;) "Shortwave Sportfishing" wrote in message ... On 27 Apr 2005 02:07:48 -0700, wrote: Thanks anybody for the inputs! I am hesitating between a boat weighting 440 pounds and a very nice one weighting around 1000 pounds. Will a 12V 55 lb motor with two batteries (in parallel?) do the job still as fine? No problem - in fact the 55 may be a little over kill, but hey - MORE POWER!!! :) Good luck. Later, Tom |
Shortwave Sportfishing writes:
Not a good idee. Really? Why? Any mismatch is destructive, and eventually, they will mismatch. |
On Wed, 27 Apr 2005 20:22:30 -0500, Richard J Kinch
wrote: Shortwave Sportfishing writes: Not a good idee. Really? Why? Any mismatch is destructive, and eventually, they will mismatch. Give me some specifics. Later, Tom |
Richard J Kinch Apr 27, 6:22 pm show options
Newsgroups: rec.boats From: Richard J Kinch - Find messages by this author Date: Wed, 27 Apr 2005 20:22:30 -0500 Local: Wed,Apr 27 2005 6:22 pm Subject: Minn Kota 12V or 24V Reply | Reply to Author | Forward | Print | Individual Message | Show original | Report Abuse Shortwave Sportfishing writes: Not a good idee. Really? Why? Any mismatch is destructive, and eventually, they will mismatch. I really don't know what you mean by "destructive" Two equally good batteries should work fine. Eventually,one bad battery can, and usually will drain the good one, but it won't ruin anything that I know of. |
Tim writes:
Any mismatch is destructive, and eventually, they will mismatch. I really don't know what you mean by "destructive" Two equally good batteries should work fine. No. Currents are at best unstably balanced. Any mismatch (difference) in the cells (size, manufacturer, model, flooded/sealed/gel/etc, date of manufacture, age, prior application, usage history) at the start or developing over time will result in loads between the batteries themselves, which over time will accelerate the mismatching process. A shorted cell, not uncommon, will result in enormous currents that can cause a fire or explosion. I know it is done, but only as a compromise, and a bad one at that. I would at least put fusible links in series with each battery before the parallel connection. That will at least give some protection against the fire and explosion hazard. Think of it as yoking a strong horse and a weak horse to a cart side by side. The strong horse will be spent dragging the weak one. The weak one will be spent just trying to keep up with the strong. The power to the cart is a fraction of what the team is exerting. |
Amps ...
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On Thu, 28 Apr 2005 16:56:12 -0500, Richard J Kinch
wrote: Tim writes: Any mismatch is destructive, and eventually, they will mismatch. I really don't know what you mean by "destructive" Two equally good batteries should work fine. No. Currents are at best unstably balanced. Any mismatch (difference) in the cells (size, manufacturer, model, flooded/sealed/gel/etc, date of manufacture, age, prior application, usage history) at the start or developing over time will result in loads between the batteries themselves, which over time will accelerate the mismatching process. A shorted cell, not uncommon, will result in enormous currents that can cause a fire or explosion. I know it is done, but only as a compromise, and a bad one at that. I would at least put fusible links in series with each battery before the parallel connection. That will at least give some protection against the fire and explosion hazard. Think of it as yoking a strong horse and a weak horse to a cart side by side. The strong horse will be spent dragging the weak one. The weak one will be spent just trying to keep up with the strong. The power to the cart is a fraction of what the team is exerting. Whatever. Later, Tom |
"Shortwave Sportfishing" wrote in message ... On Thu, 28 Apr 2005 16:56:12 -0500, Richard J Kinch wrote: Tim writes: Any mismatch is destructive, and eventually, they will mismatch. I really don't know what you mean by "destructive" Two equally good batteries should work fine. No. Currents are at best unstably balanced. Any mismatch (difference) in the cells (size, manufacturer, model, flooded/sealed/gel/etc, date of manufacture, age, prior application, usage history) at the start or developing over time will result in loads between the batteries themselves, which over time will accelerate the mismatching process. A shorted cell, not uncommon, will result in enormous currents that can cause a fire or explosion. I know it is done, but only as a compromise, and a bad one at that. I would at least put fusible links in series with each battery before the parallel connection. That will at least give some protection against the fire and explosion hazard. Think of it as yoking a strong horse and a weak horse to a cart side by side. The strong horse will be spent dragging the weak one. The weak one will be spent just trying to keep up with the strong. The power to the cart is a fraction of what the team is exerting. Whatever. Later, Tom I guess I better disconnect the 2nd factory battery in my Duramax Diesel pickumup. |
Bill McKee writes:
I guess I better disconnect the 2nd factory battery in my Duramax Diesel pickumup. What you have is a compromised, but not uncommon, design. The biggest batteries commonly sold aren't big enough for starting diesels. It would be better if they put two 6V of the same size in series, or used a 24V starter from two 12V in series, but it's cheapest to do it like you have. |
"Richard J Kinch" wrote in message .. . Bill McKee writes: I guess I better disconnect the 2nd factory battery in my Duramax Diesel pickumup. What you have is a compromised, but not uncommon, design. The biggest batteries commonly sold aren't big enough for starting diesels. It would be better if they put two 6V of the same size in series, or used a 24V starter from two 12V in series, but it's cheapest to do it like you have. woooooooooosh |
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On Fri, 29 Apr 2005 02:50:33 GMT, "Bill McKee"
wrote: "Shortwave Sportfishing" wrote in message .. . On Thu, 28 Apr 2005 16:56:12 -0500, Richard J Kinch wrote: Tim writes: Any mismatch is destructive, and eventually, they will mismatch. I really don't know what you mean by "destructive" Two equally good batteries should work fine. No. Currents are at best unstably balanced. Any mismatch (difference) in the cells (size, manufacturer, model, flooded/sealed/gel/etc, date of manufacture, age, prior application, usage history) at the start or developing over time will result in loads between the batteries themselves, which over time will accelerate the mismatching process. A shorted cell, not uncommon, will result in enormous currents that can cause a fire or explosion. I know it is done, but only as a compromise, and a bad one at that. I would at least put fusible links in series with each battery before the parallel connection. That will at least give some protection against the fire and explosion hazard. Think of it as yoking a strong horse and a weak horse to a cart side by side. The strong horse will be spent dragging the weak one. The weak one will be spent just trying to keep up with the strong. The power to the cart is a fraction of what the team is exerting. Whatever. I guess I better disconnect the 2nd factory battery in my Duramax Diesel pickumup. Yes - I must go out and disconnect my diesel batteries in my pickup truck right now - they might be unstable. Oh, and my '50 MTA International tractor - can't have that being unstable. I'll just have to figure out another way to start it - maybe like pushing it downhill. Oh, and the storage batteries that buffer the diesel generator for the house and barn. I forgot all those diesel electric subs - hell, subs are dangerous enough, can't have unstable batteries. They are all unstable, YOU HEAR ME!! UNSTABLE!!! I also need to get to my professors - if they are still alive - and tell them that parallel batteries are verboten because the circuit is unstable. Here's a quote and a reference: "Failure mechanisms of deep cycle batteries are described on pages 14-97 thru 14-98 of reference 1. Grid corrosion and plate shedding are the predominant failures. Neither is a result of parallel connections." http://www.amplepower.com/pwrnews/parallel/ Might want to take a look at this one while you are at it. http://www.batteryuniversity.com/partone-24.htm I just can't resist - here's one more. http://www.wagonmaker.com/newbatt.html And let's not leave a manufacturer out of this: http://tinyurl.com/acvgb I have no freakin' idea what this is all about, but it is described as a Intra/Extra Dimensional Shift - anybody ever watch "Sliders"? http://nadia.delicata.net/appendixVI.htm Later, Tom |
Perhaps I wasn't clear. Paralleling lead-acid batteries is done, but
its not a good idea. If series is possible then use series. I believe your reports of using them all over diesels where there is no other option that cheap, but that doesn't mean it is a good idea for a little trolling motor. Shortwave Sportfishing writes: "Failure mechanisms of deep cycle batteries are described on pages 14-97 thru 14-98 of reference 1. Grid corrosion and plate shedding are the predominant failures. Neither is a result of parallel connections." A thoroughly shallow analysis, followed by ignorant opinions like: "a cell rarely, if ever, shorts with a low resistance". All from somebody trying to sell you something. I suppose if you have never seen a car battery explode, you might not believe the warnings, or at least you might not treat them with respect. I know I didn't, until it happened. I still jump car batteries when the need arises, but believe me, I do it with care and wearing protective gear. I'm not gonna get in a citation war. Look at lead-acid battery mfr sites and you'll find they typically caution against paralleling if they address the issue at all. This religious advocacy of a poor practice reminds me of people who advocate using suicide cords for portable generators. Yes, they work, yes its done (and I have done it myself), but it isn't a good idea, and it risks some serious problems. |
On Sat, 30 Apr 2005 00:33:26 -0500, Richard J Kinch
wrote: ~` snippage ~~ I'm not gonna get in a citation war. Look at lead-acid battery mfr sites and you'll find they typically caution against paralleling if they address the issue at all. Look, your position is ridiculous and silly. Just admit it and move on. Later, Tom |
I guess I better disconnect the 2nd factory battery in my Duramax
Diesel pickumup. Not a bad idea...LOL! batteries can explode, I don't deny that. But if it was that great or common of an issue, then there would be all kinds of govt regulations checking for paralell and series battery applications to be in "code" Almost all your diesel Semi-trucks have not only 2 but 3 and even 4 batteries and no "diodes" or "spark arrestors" installed. they are however, mounted in a battery box which if I rememeber correctly is Coast Guard mandatory on boats anyhow. |
Richard is not so much being silly as he is being an expounder of a theory
with which he has fallen in love??? In practical terms he is full of it. Operating batteries in parallel is virtually bullet proof. Clearly he has no practical experience or his position would shift. In some ways he reminds me of the K of Oz and DFI. Butch "Tim" wrote in message oups.com... I guess I better disconnect the 2nd factory battery in my Duramax Diesel pickumup. Not a bad idea...LOL! batteries can explode, I don't deny that. But if it was that great or common of an issue, then there would be all kinds of govt regulations checking for paralell and series battery applications to be in "code" Almost all your diesel Semi-trucks have not only 2 but 3 and even 4 batteries and no "diodes" or "spark arrestors" installed. they are however, mounted in a battery box which if I rememeber correctly is Coast Guard mandatory on boats anyhow. |
On Sat, 30 Apr 2005 14:23:28 GMT, "Butch Davis"
wrote: Richard is not so much being silly as he is being an expounder of a theory with which he has fallen in love??? In practical terms he is full of it. Operating batteries in parallel is virtually bullet proof. Clearly he has no practical experience or his position would shift. In some ways he reminds me of the K of Oz and DFI. I refuse to comment other than to say... EXACTLY!!! :) I'm sure Richard has something to contribute - on this issue I'm afraid he's in a very small, and very wrong, minority. Hey, everybody has an opinion - no harm, no foul. Later, Tom |
Butch Davis writes:
Operating batteries in parallel is virtually bullet proof. Clearly he has no practical experience or his position would shift. We'll have to leave this as a distinct difference of opinion, then. |
On Sat, 30 Apr 2005 23:44:19 GMT, Gene Kearns
wrote: On Sat, 30 Apr 2005 00:33:26 -0500, Richard J Kinch wrote: Perhaps I wasn't clear. Paralleling lead-acid batteries is done, but its not a good idea. If series is possible then use series. I don't find any merit in what you offer as fact. I don't want to get into a citation war either, but short of a religious faith in safe vs. unsafe battery practices it would be nice to have a little science to back up one's words. I, too, have seen the explosion (and thermal runaway) of batteries, but I believe it made not a whit of difference whether the battery was paralleled or in series. If you have some sort of objective scientific explanation reaching beyond having seen a car battery explode and consequently becoming afraid of them.... I'd like to hear it. The only thermal runaway I have ever personally witnessed was an industrial application in which temperature extremes caused a situation in which the charger overcompensated starting for a low temp condition and continuing through a high temp condition. The temp compensator circuit was faulty. That was the only situation I have ever watched personally. I've worked on investigations of thermal runaway, but they almost always were caused by this same condition - the temp compensation was faulty. You see this type of condition with BBU systems also. These were/are not your everyday run of the mill lead acid starting or trolling batteries though. They were rapid charge/discharge batteries which are not seen in daily applications being special purpose. To give Richard his do, there have been some reports of AGM batteries having thermal failure as a result of inappropriate application. These have all been misapplication of the AGM technology rather than a fault in the system themselves. In one reported case, a garage mechanic just slapped a rapid charger on an AGM battery and it went kablooey. These seem to be few and far between however and mostly related to RVs which somehow figures. To get back to the main discussion point - in basic service, with lead acid batteries parallel circuits are as safe as can be and unless somebody is a complete and total idiot, almost impossible to screw up or blow up due to the basic nature of the circuit itself. Later, Tom |
"Gene Kearns" wrote in message ... On Sun, 01 May 2005 00:56:14 GMT, Shortwave Sportfishing wrote: The only thermal runaway I have ever personally witnessed was an industrial application in which temperature extremes caused a situation In truth, the only thermal runaways I have ever witnessed were nicad batteries designed for starting turbine engines...... .... not unheard of, but quite spectacular... lead-acid explosions, I think, fall into another category... -- Grady-White Gulfstream, out of Southport, NC. http://myworkshop.idleplay.net/ Homepage* http://www.thebayguide.com/rec.boats Rec.boats at Lee Yeaton's Bayguide The only lead-acid battery explosion I ever witnessed was about 42 years ago and I removed the charger from the spare jumper battery at the service station I worked in. Small spark, big bang. Luckily the battery blew out the side away from me. |
Gene Kearns writes:
If you have some sort of objective scientific explanation reaching beyond having seen a car battery explode and consequently becoming afraid of them.... I'd like to hear it. The explanation is simply that batteries are more or less mismatched. See my earlier posts. As long as there is a mismatch, you cannot get twice the watt-hours out of a pair of batteries in parallel versus a single. One will always load the other. There is also a risk of severe overload if a cell should short; this risk is simply not present in a series arrangement; thus my recommendation to insert fusible links in each parallel branch. Aside from the output degradation, and the shorted-cell risk, yes, you can put well-matched batteries in parallel. It is common in certain applications as a compromise. If series is possible, then use series. |
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