Re: Direct Drive

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Re: Direct Drive

Mark E. Hazen-2
Lee,

We should also mention, if it hasn't been already, that direct drive also
demands much more from the batteries.

I am a strong advocate of using a transmission because it makes no sense to
place undo strain on the motor, controller and the batteries just so you
don't have to switch gears.  Neither does it make any sense to buy a larger
motor, controller and batteries than what you need for practical street use.

Racing is another case altogether.

Mark E. Hazen
EVhelp, LLC
5215 NE 14th Court
Ocala, FL 34479
352-732-8354
Cell: 352-502-6200
[hidden email]
www.evhelp.com



Message: 1
Date: Sun, 22 Feb 2009 14:18:52 -0600
From: Lee Hart <[hidden email]>
Subject: Re: [EVDL] Direct drive of pickup truck
To: Electric Vehicle Discussion List <[hidden email]>
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Roger Heuckeroth wrote:
> Oh yes I guess a electric forklift can be considered an "EV". I'll
> have to be more specific next time and say battery only electric
> street legal car or truck.  The point is when the engineers designed
> these motors they were thinking forklift, not car or truck.  Had they
> designed them for an automobile their starting parameters would have
> been different.

Yes, that is true. But, there wouldn't have been a lot of difference. A
series motor is a very common choice for direct drive EVs, of all sizes.
They're used in NEVs, cars, trucks, buses, trains, and every other type
of EV you can think of.

The only fundamental difference between a series motor designed for a
road-going EV with direct drive, and one designed for use with a
transmission, is that the direct drive motor is a little bigger. The
controller will also have to be a bit bigger, to supply the extra
current needed for faster acceleration and hills. Also, since the
internal fan won't work at low speeds, there will be an external blower
instead for cooling.

Once you get a chance to drive an EV, you'll find that even if it has a
transmission, you wind up leaving it in one or possibly two gears all
the time anyway. You make up for an undersized motor and controller by
shifting, for the steepest hills or faster acceleration.

It turns out that the weight and losses of a transmission (and the cost,
if you have to buy it) are greater than it would have been to eliminate
the transmission and use a bigger motor and controller instead.

>> For example, my Sunrise EV2 has a WarP 9" motor, 2000amp Zilla
>> controller, and 5:1 differential with no transmission. The first pack
>> will be 22 6v golf cart bateries (132v)... It's no Tesla or Tango,
>> but it's plenty of power for normal driving.

> Kodos to you for making do with what's available, and ending up with
> quite a capable EV.  Something tells me though that if someone was to
> give you a blank check to go out and have a custom motor and
> controller designed and built for the Sunrise EV2, you wouldn't end up
> with a motor just like the WarP 9 and a controller like the Z2K.  I
> would guess it would be AC, or brushless PM, and a regen capable
> controller.

No, I actually think this motor and controller are a reasonable choice.
It's not what I would pick if cost were no object -- but then we'd be
producing yet another $100,000 car that almost no one can afford. Such
cars are rich people's toys -- they don't get driven, and won't have any
real effect on the world.

> Also, the pickup conversion that started out this thread is far from
> being a Sunrise. That was who I was replying to.  Would you recommend
> a direct drive for that conversion? You have so much more flexibility
> with keeping the tranny, and it helps keep your amps low which is
> better for your batteries and motor.

If you already have the transmission, it's easier to keep it. It can
save you money on your motor and controller, too.

But, we converted a 1987 Corvette and a GM full-size van into EVs
*without* the transmission. In the case of the Corvette, the 4-speed
transmission is rare and very expensive; so we used a NetGain TransWarp
11" motor, Zilla 2k controller, and 4.88:1 differential. The van is for
an in-city delivery truck to service vending machines, and won't need
freeway speeds, so it is geared lower. It also has the 11" motor and
Zilla controller. Leaving out the transmission on it saves room (the
motor is where the transmission used to be), which saves room under the
hood.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net


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Re: Direct Drive

Lee Hart
Mark E. Hazen wrote:
> We should also mention, if it hasn't been already, that direct drive also
> demands much more from the batteries.

No; direct drive has no real effect on the batteries. They see the same
load, because the controller just steps the voltage down more (and the
current up more) to make up for lack of lower gears.

> I am a strong advocate of using a transmission because it makes no sense to
> place undo strain on the motor, controller and the batteries just so you
> don't have to switch gears.  Neither does it make any sense to buy a larger
> motor, controller and batteries than what you need for practical street use.

Look, this is really pretty simple. Suppose your transmission has a 2:1
reduction in 2nd gear, and 1:1 in 4th gear. If you don't use 2nd gear,
the motor needs to be able to produce twice the torque, and the
controller needs to deliver twice the current. This moves you from (say)
a 500 amp Curtis controller to a 1000 amp Zilla controller. It also
moves you from an ADC L91 6.7" motor to an ADC 9" motor.

The larger motor and controller aren't under any more strain with direct
drive than the smaller motor and controller with a transmission.

If you have the transmission "for free" (i.e. it came with the car),
then keep it. If you don't have the transmission and would have to buy
one, the end result will be lighter and cheaper with the bigger motor
and controller, and *no* transmission.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Re: Direct Drive

John Lussmyer
Lee Hart wrote:
> If you have the transmission "for free" (i.e. it came with the car),
> then keep it. If you don't have the transmission and would have to buy
> one, the end result will be lighter and cheaper with the bigger motor
> and controller, and *no* transmission.
>  

This really makes me tempted to try just sticking my transmission in an
appropriate gear, and not bother with cutting the hole in the floor for
the shift, or bother installing something to engage/disengage the clutch.
(This is on my F-250 conversion)
Of course, first I need to figure out WHICH gear to stick the
transmission into.

--
--
John G. Lussmyer  mailto:[hidden email]
Electric Vehicle Battery Monitoring Systems, http://www.CasaDelGato.com


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Re: Direct Drive

Roger Heuckeroth
Are you running those twin motors with a z2k?  If so, you can probably  
skip the tranny completely. However since you have it already hooked  
up to the tranny, you may just go ahead and try leaving it in 3rd.  
What about reverse? Electric?

Sent from my iPhone

On Feb 23, 2009, at 7:14 PM, "John G. Lussmyer"  
<[hidden email]> wrote:

> Lee Hart wrote:
>> If you have the transmission "for free" (i.e. it came with the car),
>> then keep it. If you don't have the transmission and would have to  
>> buy
>> one, the end result will be lighter and cheaper with the bigger motor
>> and controller, and *no* transmission.
>>
>
> This really makes me tempted to try just sticking my transmission in  
> an
> appropriate gear, and not bother with cutting the hole in the floor  
> for
> the shift, or bother installing something to engage/disengage the  
> clutch.
> (This is on my F-250 conversion)
> Of course, first I need to figure out WHICH gear to stick the
> transmission into.
>
> --
> --
> John G. Lussmyer      mailto:[hidden email]
> Electric Vehicle Battery Monitoring Systems, http://
> www.CasaDelGato.com
>
>
> _______________________________________________
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> Usage guidelines: http://evdl.org/help/index.html#conv
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>

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Re: Direct Drive

John Lussmyer
Roger Heuckeroth wrote:
> Are you running those twin motors with a z2k?  If so, you can probably  
> skip the tranny completely. However since you have it already hooked  
> up to the tranny, you may just go ahead and try leaving it in 3rd.  
> What about reverse? Electric?
>  

Hmm, I need the transmission for Reverse.  urgh.  Guess I'll need the
shift...  (Though I may not bother with the clutch at first.)

--
--
John G. Lussmyer  mailto:[hidden email]
Electric Vehicle Battery Monitoring Systems, http://www.CasaDelGato.com


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Re: Direct Drive

David Dymaxion
In reply to this post by Lee Hart
Lee, do you ever use 1st gear, like for climbing a steep hill? I'm also curious how direct drive does climbing a steep hill. That seems like the acid test for tranny vs. direct drive.

With the EV1 I climbed some pretty steep hills no problem, but I'm curious if DC direct drivers have had any issues.




________________________________
From: Lee Hart <[hidden email]>
To: Electric Vehicle Discussion List <[hidden email]>
Sent: Monday, February 23, 2009 4:51:03 PM
Subject: Re: [EVDL] Direct Drive

Mark E. Hazen wrote:
> We should also mention, if it hasn't been already, that direct drive also
> demands much more from the batteries.

No; direct drive has no real effect on the batteries. They see the same
load, because the controller just steps the voltage down more (and the
current up more) to make up for lack of lower gears.

> I am a strong advocate of using a transmission because it makes no sense to
> place undo strain on the motor, controller and the batteries just so you
> don't have to switch gears.  Neither does it make any sense to buy a larger
> motor, controller and batteries than what you need for practical street use.

Look, this is really pretty simple. Suppose your transmission has a 2:1
reduction in 2nd gear, and 1:1 in 4th gear. If you don't use 2nd gear,
the motor needs to be able to produce twice the torque, and the
controller needs to deliver twice the current. This moves you from (say)
a 500 amp Curtis controller to a 1000 amp Zilla controller. It also
moves you from an ADC L91 6.7" motor to an ADC 9" motor.

The larger motor and controller aren't under any more strain with direct
drive than the smaller motor and controller with a transmission.

If you have the transmission "for free" (i.e. it came with the car),
then keep it. If you don't have the transmission and would have to buy
one, the end result will be lighter and cheaper with the bigger motor
and controller, and *no* transmission.


     
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Re: Direct Drive

Roger Heuckeroth
In reply to this post by John Lussmyer


Sent from my iPhone

On Feb 23, 2009, at 10:44 PM, "John G. Lussmyer"  
<[hidden email]> wrote:

> Roger Heuckeroth wrote:
>> Are you running those twin motors with a z2k?  If so, you can  
>> probably
>> skip the tranny completely. However since you have it already hooked
>> up to the tranny, you may just go ahead and try leaving it in 3rd.
>> What about reverse? Electric?
>>
>
> Hmm, I need the transmission for Reverse.  urgh.  Guess I'll need the
> shift...  (Though I may not bother with the clutch at first.)

I'm keeping the tranny as well, but I'm going to try clutchless. I  
designed the adapter such that the spacing will allow addition of a  
clutch and flywheel if I ever change my mind.

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Re: Direct Drive

Lee Hart
In reply to this post by David Dymaxion
David Dymaxion wrote:
> Lee, do you ever use 1st gear, like for climbing a steep hill? I'm
> also curious how direct drive does climbing a steep hill. That seems
> like the acid test for tranny vs. direct drive.

No; I never use first gear for any normal driving, no matter how steep
the hill. First is just if I need to really creep along, or if I want to
impress some teenager and burn rubber.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Re: Direct Drive

Rick Beebe
In reply to this post by Mark E. Hazen-2
Mark E. Hazen wrote:
> Lee,
>
> We should also mention, if it hasn't been already, that direct drive also
> demands much more from the batteries.
>
> I am a strong advocate of using a transmission because it makes no sense to
> place undo strain on the motor, controller and the batteries just so you
> don't have to switch gears.  Neither does it make any sense to buy a larger
> motor, controller and batteries than what you need for practical street use.

There is some small amount of efficiency loss in a transmission that
annoys purists like me. The tranny is there to solve a problem--torque
over a narrow rpm range--that electric motors don't really have. I feel
it doesn't make sense to have a box spinning 5 gear sets when you'll
only ever use one or two of them.

There are other advantages with small vehicles. The tranny in my car
weighs 80 pounds. With it out I could add 80 pounds more battery. With
the motor in the back near the differential I'd have space under the
hood for another three batteries and there's potential space in the now
unused tunnel for batteries or electronics.

The vast majority of cars sold in the US now have automatic
transmissions. If you're making cars for mass consumption (defined
however you want) you'll appeal to a larger market with just a
forward/reverse/park lever.

That said, for most of us the transmission is "free" and is by far the
easiest way of connecting a motor to the drive train. The relatively
small RPM range of the series DC motors also often necessitates a tranny
to get acceptable speed range.

--Rick

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Re: direct drive

Brian D. Hall
In reply to this post by Mark E. Hazen-2
This Debate has been around for awhile, as well as AC vs DC. I am in
favor of a transmission with a clutch. I have replaced too many
transmissions in ev's without clutches to know the benefit of a
clutch.Guess folks think it's easier to replace the transmission than
to add a fly wheel and clutch. I know many of you out there are
driving  clutch-less ev's with no problem, But would you let anyone
drive it ?
Oh, I was going to write about transmissions, to be short, My Geo
metro with an ac-31 draws 500 amps if I take off in 3rd gear, it only
draws about 150 in 1st gear.Yes you can start off in 3rd gear and just
leave it there, but my range and battery life is going to suffer. Just
my 1/2 watts worth, Brian



Mark E. Hazen wrote:
> Lee,
>
> We should also mention, if it hasn't been already, that direct drive also
> demands much more from the batteries.
>
> I am a strong advocate of using a transmission because it makes no sense to
> place undo strain on the motor, controller and the batteries just so you
> don't have to switch gears.  Neither does it make any sense to buy a larger
> motor, controller and batteries than what you need for practical street use.

.There is some small amount of efficiency loss in a transmission that
.annoys purists like me. The tranny is there to solve a problem--torque
.over a narrow rpm range--that electric motors don't really have. I feel
.it doesn't make sense to have a box spinning 5 gear sets when you'll
.only ever use one or two of them.

.There are other advantages with small vehicles. The tranny in my car
.weighs 80 pounds. With it out I could add 80 pounds more battery. With
.the motor in the back near the differential I'd have space under the
.hood for another three batteries and there's potential space in the now
.unused tunnel for batteries or electronics.

.The vast majority of cars sold in the US now have automatic
.transmissions. If you're making cars for mass consumption (defined
.however you want) you'll appeal to a larger market with just a
.forward/reverse/park lever.

.That said, for most of us the transmission is "free" and is by far the
.easiest way of connecting a motor to the drive train. The relatively
.small RPM range of the series DC motors also often necessitates a tranny
.to get acceptable speed range.

.--Rick

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Re: direct drive

Ray Brooks
As an alternative clutch Google Ram Coupler.


----- Original Message -----
From: "Brian D. Hall" <[hidden email]>
To: <[hidden email]>
Sent: Tuesday, February 24, 2009 6:37 PM
Subject: Re: [EVDL] direct drive


> This Debate has been around for awhile, as well as AC vs DC. I am in
> favor of a transmission with a clutch. I have replaced too many
> transmissions in ev's without clutches to know the benefit of a
> clutch.Guess folks think it's easier to replace the transmission than
> to add a fly wheel and clutch. I know many of you out there are
> driving  clutch-less ev's with no problem, But would you let anyone
> drive it ?
> Oh, I was going to write about transmissions, to be short, My Geo
> metro with an ac-31 draws 500 amps if I take off in 3rd gear, it only
> draws about 150 in 1st gear.Yes you can start off in 3rd gear and just
> leave it there, but my range and battery life is going to suffer. Just
> my 1/2 watts worth, Brian
>
>
>
> Mark E. Hazen wrote:
>> Lee,
>>
>> We should also mention, if it hasn't been already, that direct drive also
>> demands much more from the batteries.
>>
>> I am a strong advocate of using a transmission because it makes no sense
>> to
>> place undo strain on the motor, controller and the batteries just so you
>> don't have to switch gears.  Neither does it make any sense to buy a
>> larger
>> motor, controller and batteries than what you need for practical street
>> use.
>
> .There is some small amount of efficiency loss in a transmission that
> .annoys purists like me. The tranny is there to solve a problem--torque
> .over a narrow rpm range--that electric motors don't really have. I feel
> .it doesn't make sense to have a box spinning 5 gear sets when you'll
> .only ever use one or two of them.
>
> .There are other advantages with small vehicles. The tranny in my car
> .weighs 80 pounds. With it out I could add 80 pounds more battery. With
> .the motor in the back near the differential I'd have space under the
> .hood for another three batteries and there's potential space in the now
> .unused tunnel for batteries or electronics.
>
> .The vast majority of cars sold in the US now have automatic
> .transmissions. If you're making cars for mass consumption (defined
> .however you want) you'll appeal to a larger market with just a
> .forward/reverse/park lever.
>
> .That said, for most of us the transmission is "free" and is by far the
> .easiest way of connecting a motor to the drive train. The relatively
> .small RPM range of the series DC motors also often necessitates a tranny
> .to get acceptable speed range.
>
> .--Rick
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>


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Re: Direct Drive

CHARLIEP
In reply to this post by David Dymaxion

David Dymaxion wrote
Lee, do you ever use 1st gear, like for climbing a steep hill? I'm also curious how direct drive does climbing a steep hill. That seems like the acid test for tranny vs. direct drive.

With the EV1 I climbed some pretty steep hills no problem, but I'm curious if DC direct drivers have had any issues.




________________________________
From: Lee Hart <leeahart@earthlink.net>
To: Electric Vehicle Discussion List <ev@lists.sjsu.edu>
Sent: Monday, February 23, 2009 4:51:03 PM
Subject: Re: [EVDL] Direct Drive

Mark E. Hazen wrote:
> We should also mention, if it hasn't been already, that direct drive also
> demands much more from the batteries.

No; direct drive has no real effect on the batteries. They see the same
load, because the controller just steps the voltage down more (and the
current up more) to make up for lack of lower gears.

> I am a strong advocate of using a transmission because it makes no sense to
> place undo strain on the motor, controller and the batteries just so you
> don't have to switch gears.  Neither does it make any sense to buy a larger
> motor, controller and batteries than what you need for practical street use.

Look, this is really pretty simple. Suppose your transmission has a 2:1
reduction in 2nd gear, and 1:1 in 4th gear. If you don't use 2nd gear,
the motor needs to be able to produce twice the torque, and the
controller needs to deliver twice the current. This moves you from (say)
a 500 amp Curtis controller to a 1000 amp Zilla controller. It also
moves you from an ADC L91 6.7" motor to an ADC 9" motor.

The larger motor and controller aren't under any more strain with direct
drive than the smaller motor and controller with a transmission.

If you have the transmission "for free" (i.e. it came with the car),
then keep it. If you don't have the transmission and would have to buy
one, the end result will be lighter and cheaper with the bigger motor
and controller, and *no* transmission.


     
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Re: Direct Drive

CHARLIEP
In reply to this post by John Lussmyer

John G. Lussmyer wrote
Lee Hart wrote:
> If you have the transmission "for free" (i.e. it came with the car),
> then keep it. If you don't have the transmission and would have to buy
> one, the end result will be lighter and cheaper with the bigger motor
> and controller, and *no* transmission.
>  

This really makes me tempted to try just sticking my transmission in an
appropriate gear, and not bother with cutting the hole in the floor for
the shift, or bother installing something to engage/disengage the clutch.
(This is on my F-250 conversion)
Of course, first I need to figure out WHICH gear to stick the
transmission into.

--
--
John G. Lussmyer  mailto:Cougar@CasaDelGato.Com
Electric Vehicle Battery Monitoring Systems, http://www.CasaDelGato.com


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Re: Direct Drive

CHARLIEP

Charlie P wrote
a used transmission ranges from 50 dollars to 250dollars how does this compare to cost of larger motor and controller?
John G. Lussmyer wrote
Lee Hart wrote:
> If you have the transmission "for free" (i.e. it came with the car),
> then keep it. If you don't have the transmission and would have to buy
> one, the end result will be lighter and cheaper with the bigger motor
> and controller, and *no* transmission.
>  

This really makes me tempted to try just sticking my transmission in an
appropriate gear, and not bother with cutting the hole in the floor for
the shift, or bother installing something to engage/disengage the clutch.
(This is on my F-250 conversion)
Of course, first I need to figure out WHICH gear to stick the
transmission into.

--
--
John G. Lussmyer  mailto:Cougar@CasaDelGato.Com
Electric Vehicle Battery Monitoring Systems, http://www.CasaDelGato.com


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Re: Direct Drive

CHARLIEP

Charlie P wrote
in a f250 you will often find you need gear changes, cut the hole ,respectfully C p
Charlie P wrote
a used transmission ranges from 50 dollars to 250dollars how does this compare to cost of larger motor and controller?
John G. Lussmyer wrote
Lee Hart wrote:
> If you have the transmission "for free" (i.e. it came with the car),
> then keep it. If you don't have the transmission and would have to buy
> one, the end result will be lighter and cheaper with the bigger motor
> and controller, and *no* transmission.
>  

This really makes me tempted to try just sticking my transmission in an
appropriate gear, and not bother with cutting the hole in the floor for
the shift, or bother installing something to engage/disengage the clutch.
(This is on my F-250 conversion)
Of course, first I need to figure out WHICH gear to stick the
transmission into.

--
--
John G. Lussmyer  mailto:Cougar@CasaDelGato.Com
Electric Vehicle Battery Monitoring Systems, http://www.CasaDelGato.com


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Re: Direct Drive

Lee Hart
In reply to this post by CHARLIEP
Charlie P wrote:
(nothing)

Charlie, either you hit "send" before you wrote anything, or your email
software is set up to use some unreadable format.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Re: Direct Drive

Lee Hart
In reply to this post by CHARLIEP
Charlie P wrote:
>> a used transmission ranges from 50 dollars to 250dollars how does this
>> compare to cost of larger motor and controller?

That's similar in price to buying a larger (vs a smaller) used motor and
controller.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Re: Direct Drive

CHARLIEP
In reply to this post by David Dymaxion
David Dymaxion wrote
Lee, do you ever use 1st gear, like for climbing a steep hill? I'm also curious how direct drive does climbing a steep hill. That seems like the acid test for tranny vs. direct drive. With the EV1 I climbed some pretty steep hills no problem, but I'm curious if DC direct drivers have had any issues. Used trannys are a dime a dozen what do larger motors and controllers cost? in the thousands.,If you can find them especialy controllers ________________________________ From: Lee Hart <leeahart@earthlink.net> To: Electric Vehicle Discussion List <ev@lists.sjsu.edu> Sent: Monday, February 23, 2009 4:51:03 PM Subject: Re: [EVDL] Direct Drive Mark E. Hazen wrote: > We should also mention, if it hasn't been already, that direct drive also > demands much more from the batteries. No; direct drive has no real effect on the batteries. They see the same load, because the controller just steps the voltage down more (and the current up more) to make up for lack of lower gears. > I am a strong advocate of using a transmission because it makes no sense to > place undo strain on the motor, controller and the batteries just so you > don't have to switch gears. Neither does it make any sense to buy a larger > motor, controller and batteries than what you need for practical street use. Look, this is really pretty simple. Suppose your transmission has a 2:1 reduction in 2nd gear, and 1:1 in 4th gear. If you don't use 2nd gear, the motor needs to be able to produce twice the torque, and the controller needs to deliver twice the current. This moves you from (say) a 500 amp Curtis controller to a 1000 amp Zilla controller. It also moves you from an ADC L91 6.7" motor to an ADC 9" motor. The larger motor and controller aren't under any more strain with direct drive than the smaller motor and controller with a transmission. If you have the transmission "for free" (i.e. it came with the car), then keep it. If you don't have the transmission and would have to buy one, the end result will be lighter and cheaper with the bigger motor and controller, and *no* transmission. _______________________________________________ General EVDL support: http://evdl.org/help/ Usage guidelines: http://evdl.org/help/index.html#conv Archives: http://evdl.org/archive/ Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
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Re: Direct Drive

Grant Stockly
In reply to this post by Lee Hart
At 08:45 PM 2/24/2009, you wrote:
>Charlie P wrote:
> >> a used transmission ranges from 50 dollars to 250dollars how does this
> >> compare to cost of larger motor and controller?
>
>That's similar in price to buying a larger (vs a smaller) used motor and
>controller.

There are possibly benefits to not having as much drag on the
motor.  Truck transmissions can get quite warm on the highway.



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