Thursday, December 31, 2009

[Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

LOL! Yeah, I forgot he was talking about an outboard. Still, I'd use a flexible coupling in that application, too. Just torquing the motor bolts could put undue stress on the bearings. If the shaft was unsupported at the upper end, you might get away with no flex coupler since the flexing of the shaft itself would take care of a lot of radial flex. However, by eliminating the spline connection, you lose axial movement. Differential expansion and contraction of the aluminum outboard motor lower end and the steel shaft could put some load on the bearings, reducing their lifespan. I have three $3000 vacuum pumps at work. All are C-mount and short-coupled between motor and pump, and they all have a flex connection between them. Never had a bearing or pump seal problem and they have run 8 hours a day for over 8 years. Or, to put it a better way, a lovejoy connector is a lot less expensive than a set of motor bearings, let along the inconvenience of being stranded on the water, or the time it takes to change out bearings.

--- In electricboats@yahoogroups.com, "im_searchin" <axius@...> wrote:
>
> ????
> I am totally puzzled for two reasons;
> 1. I have been the owner of many of the millions of boats with the prop shaft hard connected to the motor. 0.0005 per inch of coupling face is the standard alignment spec. This is the same spec for aligning electric motors in industrial applications. Lovejoy and other couplings are for low hp applications and to minimize shock load. You line up a LoveJoy exactly the same way, before installing the rubber cross.
>
> 2. This is an OUTBOARD MOTOR the fellow is connecting to so what does the flex of the hull have to do with the coupling?
>
>
>
> --- In electricboats@yahoogroups.com, danbollinger <no_reply@> wrote:
> >
> > Myles, The "guarantee" is the splendid bit of engineering you do that calculated the shear values. The fellow wanted to avoid welding and machining, which is why I came up with this solution.
> >
> > When I said "buy a coupler" I meant one of the many types that allow movement and misalignment like a Lovejoy connector. Prop shafts should never be hard connected to motors, especially in boats because the boat itself can flex, causing excessive force on the motor bearings.
>

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Posted by at No comments:

Re: [Electric Boats] AGM Battery: To Float Or Not To Float

 

Mike,

Why does your marina not allow electric to the boat during the winter? The expense of electric heaters running?

I was able to get the Harbor to drop the "Utility Charge" from my slip fee. I am using shore power to keep my batteries topped off and use very little electricity. It took a while but they agreed that the effort (expense) I have put into this "Green Technology" should not penalized. Initially they were lumping my battery float charging in with boats that were hooked up to shore power for refrigeration and other uses.

Have you talked to your marina about your intended use?

Mark

--- In electricboats@yahoogroups.com, Mike <biankablog@...> wrote:
>
> "For battery LONGEVITY, is it preferable to have the battery absorb every last bit of energy and sit there fully charged with an external float charger (set to, e.g., 13.2v at 70degF), or is simply turning off everything when float current gets below a certain point preferable?"
>  
> Joe:
>      There are no bad or old questions here just new opportunities to learn something. New people are joining the list with new ideas and expertise all the time. Your question is something I have been wondering about too. I've charged my 48 volt 200 amp AGM  battery bank up to full charge and then shutdown the charger because my boatyard will not allow any AC lines going to boats over the winter. So I am relying on the wind generator and solar panel to keep things charged up until I next check on the boat and plug in the AC charger. I have been wondering if this is the best way to store and charge my AGM's over the winter too. So far the batteries have been holding up using this system but, I'm not sure if it is the best way to store the AGM batteries over the winter. Since I'd rather not think about taking them off the boat every year.
>
>  
> Capt. Mike
> http://biankablog.blogspot.com
>
> --- On Thu, 12/31/09, joemultihuller <siudzinski@...> wrote:
>
>
> From: joemultihuller <siudzinski@...>
> Subject: [Electric Boats] AGM Battery: To Float Or Not To Float
> To: electricboats@yahoogroups.com
> Date: Thursday, December 31, 2009, 5:53 PM
>
>
>  
>
>
>
> BACKGROUND
>
> I am running a string of Optima Yellow Tops, each one with its own dedicated isolated charger. My present daily non-marine use typically discharges the bank less than 30% of full capacity (i.e., I rarely go below 70% of full charge), with charging immediately after use. I have no parasitic loads after I turn everything off, and these batteries can maintain their fully-charged state for months.
>
> Some chargers, e.g., West Marine's programmable 30A unit, consider charging complete when the battery draws less than about 0.85A at their float voltage of 13.4v (65degF), at which point the charger turns off. The charger then cycles on for a few seconds at lengthy intervals (minutes to hours), and then shuts back off when that lower current limit is again reached.
>
> Other chargers simply maintain a constant float voltage (13.2v - 13.4v at 70degF), and the battery itself determines how much current it wants - over a day or two, the current draw decreases until it finally stabilizes in the low milliamp range for a healthy battery.
>
> Contrasting these two techniques simply tells me that the former charges the battery to maybe 98% whereas the latter stuffs that additional 2% of energy into the battery. The difference is inconsequential to me as I never approach a full drawdown of the batteries.
>
> The QUESTION on the table:
>
> For battery LONGEVITY, is it preferable to have the battery absorb every last bit of energy and sit there fully charged with an external float charger (set to, e.g., 13.2v at 70degF), or is simply turning off everything when float current gets below a certain point preferable?
>
> My reason for asking is that I have a whole bunch of different chargers and can program just about any scenario (including 'desulphation' pulsing), and am looking to optimize my final installation which I plan to migrate to the boat.
>
> Thanks in advance for your advice, and sorry to belabor what is probably an old topic but one which I could not find an answer to.
>
> JoeS.
>

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Posted by at No comments:

[Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

Obviously I was thinking direct-drive in my last post. With belts the alignment is simpler. Consider using QD bushing pulleys:
http://www.mcmaster.com/#quick-disconnect-bushings/=56bqwz
(scroll about halfway down the page)
They work with an assortment of pulleys and sprockets.
Something like this might work for you:
http://www.mcmaster.com/#catalog/115/1045/=56bqc5
McMaster is not the cheapest around, but they have a lot of stuff and are easy to deal with.
I used keyed pulleys and couplers on my first inboard conversion, but once I discovered the clamp-type ones, I never went back.

--- In electricboats@yahoogroups.com, "williamdickenson55" <williamdickenson55@...> wrote:
>
> An interesting set of conversations. I was specifically trying to avoid the machine shop / welding side of the world, but it looks like I'm stuck with it. That isn't a shock, I was just hoping someone knew of a commercial adapter.
>
> I'll probably grind down a side, bore the pulley out to 9/16th, tap it with a couple of set screws, press in place (push rather hard actually) and live with it for a while.
>
> If anyone does come up with a place to buy, I'm all ears. Thanks
>

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Posted by at No comments:

[Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

Another possibility for an "off the shelf" solution...

http://www.mcmaster.com/#shaft-couplers/=56awqy
or if you'd rather have a flex coupler:
http://www.mcmaster.com/#shaft-couplers/=56bf4y

These clamp-type couplers work real well for plain shafts. No keyway needed. The fit tolerance is fairly critical, but they are easily bored to fit if you have an off-sized shaft. You might get away with clamping it right over the OD of the splines. The "teeth" would bite into the bore a little and give some extra traction.
As to the vibration concerns, when using rigid couplers, a simple way to assure alignment is to install and tighten the coupler before tightening down the motor bolts. Spin it with the mount bolts loose and see if the motor wobbles. If it does(perhaps due to the OD of the splines not being perfectly concentric with the shaft) try loosening and re-clocking the coupler till you find a sweet spot.
Flex couplers make it easier but cost more. They can also provide galvanic isolation, important if it's going to sit in saltwater. Of course the motor/mount would need to be isolated too in that case. Probably not as much of a concern with an outboard vs. inboard.

Good luck. I always wanted to try an outboard conversion, but haven't got around to it yet. Please let us all know how it works out.

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Posted by at No comments:

Re: [Electric Boats] Forward/ reverse potentiometer.

 

Mr. Searchin,
 
The throttle ramp and neutral delay parameters are set to prevent "instantaneous" switching from forward to reverse - it takes maybe a second or two to go from F to R.  The motor has plenty of power to overcome the windmill action of the prop through the water.  The delay is plenty of time to minimize the inertial load of the spinning components.
 
Denny
----- Original Message -----
Sent: Thursday, December 31, 2009 1:19 AM
Subject: Re: [Electric Boats] Forward/ reverse potentiometer.

 

Dennis;
Does the new firmware apply a low current to stop the shaft from turning before allowing your selected input to be applied? You have the mass of the prop to stop plus the speed of the water trying to spin the prop to overcome.
thanks;

--- In electricboats@yahoogroups.com, "dennis wolfe" <dwolfe@...> wrote:
>
> Matt's answer is probably the correct explanation for your hesitation but there is another possibility.
>
> Your controller knows the speed and direction of the motor shaft via the hall sensors. It may not give you reverse current until it detects the shaft has stopped moving forward.
>
> I had a real problem with my Sevcon PMAC at first. It took 15 seconds for the boat to stop coasting forward; that is a long time to wait for reverse. Sevcon changed the controller's firmware to fix the problem.
>
> Denny Wolfe
> www.wolfEboats.com
>

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.

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Posted by at No comments:

[Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

An interesting set of conversations. I was specifically trying to avoid the machine shop / welding side of the world, but it looks like I'm stuck with it. That isn't a shock, I was just hoping someone knew of a commercial adapter.

I'll probably grind down a side, bore the pulley out to 9/16th, tap it with a couple of set screws, press in place (push rather hard actually) and live with it for a while.

If anyone does come up with a place to buy, I'm all ears. Thanks

__._,_.___
.

__,_._,___
Posted by at No comments:

RE: [Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

There’s the rub as I see it---the lovejoy, in allowing some misalignment would allow the unsupported upper end of the driveshaft to deflect, compressing the lovejoy, further causing “mass imbalance”, leading to cyclic vibrations at the power head---not a good thing.  Further, this would pretty much happen as function of speed, not load.  Mass imbalance isn’t fun…when trying to machine/adapt a 14”diam conical bore prop to the straight bore/shear pin needed for my outboard prop shaft, we didn’t take the time to ensure that the resulting straight bored hole was concentric with the original conical bore.  This caused a slight mass imbalance and possibly some angular wobble offset.  The prop would work fine, but with speed, cyclic vibration was more than noticeable, it was unsettling as I feared the lower unit bearings our housing might become compromised.  We were more careful with the next prop we modified.

For those of you who know the sound and feel of a carrier bearing or u-joint going out on our car, a poorly supported upper end of an outboard driveshaft would be similar.

 

-mt

 

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of im_searchin
Sent: Wednesday, December 30, 2009 10:14 PM
To: electricboats@yahoogroups.com
Subject: [Electric Boats] Re: Source for coupler (14 spline, 5/8ths shaft) to motor or pully

 

 

????
I am totally puzzled for two reasons;
1. I have been the owner of many of the millions of boats with the prop shaft hard connected to the motor. 0.0005 per inch of coupling face is the standard alignment spec. This is the same spec for aligning electric motors in industrial applications. Lovejoy and other couplings are for low hp applications and to minimize shock load. You line up a LoveJoy exactly the same way, before installing the rubber cross.

2. This is an OUTBOARD MOTOR the fellow is connecting to so what does the flex of the hull have to do with the coupling?

--- In electricboats@yahoogroups.com, danbollinger <no_reply@...> wrote:
>
> Myles, The "guarantee" is the splendid bit of engineering you do that calculated the shear values. The fellow wanted to avoid welding and machining, which is why I came up with this solution.
>
> When I said "buy a coupler" I meant one of the many types that allow movement and misalignment like a Lovejoy connector. Prop shafts should never be hard connected to motors, especially in boats because the boat itself can flex, causing excessive force on the motor bearings.

__._,_.___
.

__,_._,___
Posted by at No comments:

Re: [Electric Boats] AGM Battery: To Float Or Not To Float

 

"For battery LONGEVITY, is it preferable to have the battery absorb every last bit of energy and sit there fully charged with an external float charger (set to, e.g., 13.2v at 70degF), or is simply turning off everything when float current gets below a certain point preferable?"
 
Joe:
     There are no bad or old questions here just new opportunities to learn something. New people are joining the list with new ideas and expertise all the time. Your question is something I have been wondering about too. I've charged my 48 volt 200 amp AGM  battery bank up to full charge and then shutdown the charger because my boatyard will not allow any AC lines going to boats over the winter. So I am relying on the wind generator and solar panel to keep things charged up until I next check on the boat and plug in the AC charger. I have been wondering if this is the best way to store and charge my AGM's over the winter too. So far the batteries have been holding up using this system but, I'm not sure if it is the best way to store the AGM batteries over the winter. Since I'd rather not think about taking them off the boat every year.
 
Capt. Mike

--- On Thu, 12/31/09, joemultihuller <siudzinski@telis.org> wrote:

From: joemultihuller <siudzinski@telis.org>
Subject: [Electric Boats] AGM Battery: To Float Or Not To Float
To: electricboats@yahoogroups.com
Date: Thursday, December 31, 2009, 5:53 PM

 
BACKGROUND

I am running a string of Optima Yellow Tops, each one with its own dedicated isolated charger. My present daily non-marine use typically discharges the bank less than 30% of full capacity (i.e., I rarely go below 70% of full charge), with charging immediately after use. I have no parasitic loads after I turn everything off, and these batteries can maintain their fully-charged state for months.

Some chargers, e.g., West Marine's programmable 30A unit, consider charging complete when the battery draws less than about 0.85A at their float voltage of 13.4v (65degF), at which point the charger turns off. The charger then cycles on for a few seconds at lengthy intervals (minutes to hours), and then shuts back off when that lower current limit is again reached.

Other chargers simply maintain a constant float voltage (13.2v - 13.4v at 70degF), and the battery itself determines how much current it wants - over a day or two, the current draw decreases until it finally stabilizes in the low milliamp range for a healthy battery.

Contrasting these two techniques simply tells me that the former charges the battery to maybe 98% whereas the latter stuffs that additional 2% of energy into the battery. The difference is inconsequential to me as I never approach a full drawdown of the batteries.

The QUESTION on the table:

For battery LONGEVITY, is it preferable to have the battery absorb every last bit of energy and sit there fully charged with an external float charger (set to, e.g., 13.2v at 70degF), or is simply turning off everything when float current gets below a certain point preferable?

My reason for asking is that I have a whole bunch of different chargers and can program just about any scenario (including 'desulphation' pulsing), and am looking to optimize my final installation which I plan to migrate to the boat.

Thanks in advance for your advice, and sorry to belabor what is probably an old topic but one which I could not find an answer to.

JoeS.

__._,_.___
.

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Posted by at No comments:

[Electric Boats] AGM Battery: To Float Or Not To Float

 

Battery life is measured in "cycles" not hours, days or years. Each time the battery is allowed to discharge and then a battery charger kicks in to re-charge the battery that is a cycle. If your battery charger is off for a specific length of time then "samples" the battery before turning itself back on, you are burning cycles - especially if some onboard item like bilge pumps, refrigeration, etc., etc., kicks on when the charger is in an "off" period.
- - Constantly "on" charge battery charges not only keep the battery topped off but they will provide the electricity to run the other equipment should they turn on. Now the battery charger is providing the electricity to run the bilge pumps, refrigeration, etc., etc. instead of the batteries.

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.

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Posted by at No comments:

[Electric Boats] AGM Battery: To Float Or Not To Float

 

BACKGROUND

I am running a string of Optima Yellow Tops, each one with its own dedicated isolated charger. My present daily non-marine use typically discharges the bank less than 30% of full capacity (i.e., I rarely go below 70% of full charge), with charging immediately after use. I have no parasitic loads after I turn everything off, and these batteries can maintain their fully-charged state for months.

Some chargers, e.g., West Marine's programmable 30A unit, consider charging complete when the battery draws less than about 0.85A at their float voltage of 13.4v (65degF), at which point the charger turns off. The charger then cycles on for a few seconds at lengthy intervals (minutes to hours), and then shuts back off when that lower current limit is again reached.

Other chargers simply maintain a constant float voltage (13.2v - 13.4v at 70degF), and the battery itself determines how much current it wants - over a day or two, the current draw decreases until it finally stabilizes in the low milliamp range for a healthy battery.

Contrasting these two techniques simply tells me that the former charges the battery to maybe 98% whereas the latter stuffs that additional 2% of energy into the battery. The difference is inconsequential to me as I never approach a full drawdown of the batteries.

The QUESTION on the table:

For battery LONGEVITY, is it preferable to have the battery absorb every last bit of energy and sit there fully charged with an external float charger (set to, e.g., 13.2v at 70degF), or is simply turning off everything when float current gets below a certain point preferable?

My reason for asking is that I have a whole bunch of different chargers and can program just about any scenario (including 'desulphation' pulsing), and am looking to optimize my final installation which I plan to migrate to the boat.

Thanks in advance for your advice, and sorry to belabor what is probably an old topic but one which I could not find an answer to.

JoeS.

__._,_.___
.

__,_._,___
Posted by at No comments:

Wednesday, December 30, 2009

Re: [Electric Boats] Forward/ reverse potentiometer.

 

Dennis;
Does the new firmware apply a low current to stop the shaft from turning before allowing your selected input to be applied? You have the mass of the prop to stop plus the speed of the water trying to spin the prop to overcome.
thanks;

--- In electricboats@yahoogroups.com, "dennis wolfe" <dwolfe@...> wrote:
>
> Matt's answer is probably the correct explanation for your hesitation but there is another possibility.
>
> Your controller knows the speed and direction of the motor shaft via the hall sensors. It may not give you reverse current until it detects the shaft has stopped moving forward.
>
> I had a real problem with my Sevcon PMAC at first. It took 15 seconds for the boat to stop coasting forward; that is a long time to wait for reverse. Sevcon changed the controller's firmware to fix the problem.
>
> Denny Wolfe
> www.wolfEboats.com
>
> ----- Original Message -----
> From: Matthew Geier
> To: electricboats@yahoogroups.com
> Sent: Thursday, December 24, 2009 4:24 PM
> Subject: Re: [Electric Boats] Forward/ reverse potentiometer.
>
>
>
> ebdrives wrote:
> > Dennis,
> >
> > I use a Merritt Joystick to run my electric 26'powerboat. It runs good to control forward/neutral/reverse, etc. But, I will tell you that there is a hesitation when I go from forward to reverse. My motor is a BLDC (brushless) motor so there is no coil to switch over into reverse.
> >
> This may not be the joystick causing the hesitation, it is probably the
> motor controller.
>
> Flipping from forward to reverse would put a lot of strain mechanically
> and electrically on the system, so when you flip the control handle from
> forward to reverse, the motor controller isn't instantly changing
> direction, but ramping the motor speed down at some pre-determined rate
> , stopping and then reversing the fields and ramping up to your throttle
> position.
> These ramp up/down rates are almost certainly programmable.
>
> I'm running a brushed motor and an Alltrax AXE, so reversing is done by
> contractors, but the forward/reverse switch is 3 way, so that 'off' has
> to be passed on the way to reverse, this causes the controller to reset
> and it then 'ramps up' at the programmed rate to the throttle setting it
> reads off the speed pot.
>
> In my case, flipping from forward to reverse with out shutting off
> would result extremely high motor currents as it fought to change
> direction against the high forward inertia of the boat. This would
> almost certainly put my motor into overload and cause the controller to
> go into current limit. It may even cause the reversing contactor to weld
> shut as it closes onto a huge current spike.
>
> So reprogramming the throttle ramp rates on your controller to get a
> 'snapper response' may not actually be a good idea.... (Assuming of
> course, that your controller allows 'in the field' changes to the
> throttle response ramp rates).
>

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.

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Posted by at No comments:
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