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Discussion Starter · #1 ·
My 1981 rabbit pickup (see sig) has a DCP 450 (Raptor) Controller. I
couldn't resist the urge to conquer a fairly major hill....according
to the emeter it was pulling between 200-250 amps all the way up. I
could tell that the 450 started limiting the amps (going into creep
mode) on the way up. My questions is this: would upgrading to a 600
allow me to pull more amps longer, or am I stressing the system way
too much already by pulling that many amps continuously....I'm sure I
will get some slap on the wrist responses, but I guess that is how we
learn...

--
Michael Mohlere
My EV: http://www.austinev.org/evalbum/296.html

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Discussion Starter · #2 ·
Hi Mike;

My Jetta has the same Rapture 450Amp controller and I have the same
issue. The cooling fan has crapped out, so it goes into thermal cutback, big
time, on a hot day. When you key "On" does the fan run a second or two, then
shut down?Like it's suposted to? On hot daze, I have had to pull over and
let it cool off.Of course you won't hear it cycling when yur going! I was
always amazed at how cool it ran, when the fan setup worked. You don't miss
it until it doesm't work.

I have a 400-450 amp hill near by, too. I can blast up at 50mph or so,
in 4th with the gas rigs if I want, but usually shortcut out about halfway,
going by the quiet residential street dignity intact. It was about 45, 50
second pull, but you could almost hear the shreek of agony of the battery.
This is using the system perfected by 18 wheelers, freight trains, roller
coasters, etc. coming DOWN the Other Side at 70!For a head start.

Seeya

Bob
----- Original Message -----
From: "Michael Mohlere" <[email protected]>
To: "EVDL" <[email protected]>
Sent: Monday, October 22, 2007 6:08 AM
Subject: [EVDL] too many amps?


> My 1981 rabbit pickup (see sig) has a DCP 450 (Raptor) Controller. I
> couldn't resist the urge to conquer a fairly major hill....according
> to the emeter it was pulling between 200-250 amps all the way up. I
> could tell that the 450 started limiting the amps (going into creep
> mode) on the way up. My questions is this: would upgrading to a 600
> allow me to pull more amps longer, or am I stressing the system way
> too much already by pulling that many amps continuously....I'm sure I
> will get some slap on the wrist responses, but I guess that is how we
> learn...
>
> --
> Michael Mohlere
> My EV: http://www.austinev.org/evalbum/296.html
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
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> Internal Virus Database is out-of-date.
> Checked by AVG Free Edition.
> Version: 7.5.488 / Virus Database: 269.13.28/1023 - Release Date:
> 9/22/2007 1:27 PM
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>

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Discussion Starter · #5 ·
Michael, my concern would be how well your motor can handle the
load. What is the continuous Amps rating on a Prestolite MTC
4002? I would hate to see the motor damaged.

Thanks,

Mike Chancey,
'88 Civic EV
Kansas City, Missouri
EV Photo Album at: http://evalbum.com
My Electric Car at: http://www.geocities.com/electric_honda
Mid-America EAA chapter at: http://maeaa.org
Join the EV List at: http://www.madkatz.com/ev/evlist.html

In medio stat virtus - Virtue is in the moderate, not the extreme
position. (Horace)

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Discussion Starter · #7 ·
Hello Michael,

You did not note what the rpm of the motor was at and what is the overall
gear ratio is.

If you are pulling 200-250 battery amps and you are limited to 450 motor
amps, the motor amps may go three times higher than the battery amps or
about 600 amps if you was not limit to 450 motor amps.

I am running a Warp 9 with a Zilla 1k with a 260 AH T-145 pack which I limit
the batteries to 400 amp maximum and the motor amps at 800 amp maximum.

The maximum motor ampere I ever pull was 600 amps for about a micro second,
500 amps for a second, 400 amps for 20 seconds, 300 amps at 20 to 30 seconds
and 200 amps continuous.

I can normally drive a 6860 lb EV at 200 motor amps on a level grade in the
city at speeds up to a maximum of 45 mph but most of the time it is at 25
mph. At 200 motor amps, I am pulling about 50 battery amps.

So this morning which is down to 40 degrees, I will tried the steepest hill
in the city which even some gas cars cannot maintain a steady speed. I turn
on the water pumps that cool the Zilla that comes from a fan cool radiator.
Also turn on the external motor fans and a external fan for additional
cooling of the Zilla.

Never went up this hill with this EV, always drove around it to my home. I
wanted to tried it once, before I pull the Warp 9 out and put back in the GE
11 that was out for maintenance.

The first 4 blocks before this hill has a slight incline, where I was up to
6000 rpm in 1st gear at 26 mph at a overall gear ratio of 19.495:1 was
pulling about 200 motor amps and 60 battery amps. As I start to go up this
hill which feels like it's a 40 degree slope, I let the speed reduce to 15
mph and held it there. The maximum battery ampere I pull was 125 amp and I
kept the motor amps at 400 amp maximum for about 20 seconds until I got to
the top of the hill.

I have temperature sensors on the Zilla heat sinks and air temperature
sensors on the exhaust port of the Zilla enclosure and motor and they read
only 10 degrees over the ambient air temperature.

With the GE-11 which is also external fan cool, I was able to do highway
driving up to 70 mph on a level and when I approach a 7 degree 2 mile long
hill to work every day, I would let it peak to 600 motor amps and let it
come down to about 200 amps, because the ICE's in front of me was slowing me
down.

In the winter when this hill was icy, I would pass a lot of these ICE up,
just walk right pass them. Running studs on all fours.

Going down this hill, I would over take the ICE's with speeds up to 80 MPH
(we had no speed limit on this road at the time) and would coast another 2
miles at the bottom of the hill, take a exit at 45 mph and then continue
down another hill and turn left right into my garage with no additional
power.

Roland


----- Original Message -----
From: "Michael Mohlere" <[email protected]>
To: "EVDL" <[email protected]>
Sent: Monday, October 22, 2007 4:08 AM
Subject: [EVDL] too many amps?


> My 1981 rabbit pickup (see sig) has a DCP 450 (Raptor) Controller. I
> couldn't resist the urge to conquer a fairly major hill....according
> to the emeter it was pulling between 200-250 amps all the way up. I
> could tell that the 450 started limiting the amps (going into creep
> mode) on the way up. My questions is this: would upgrading to a 600
> allow me to pull more amps longer, or am I stressing the system way
> too much already by pulling that many amps continuously....I'm sure I
> will get some slap on the wrist responses, but I guess that is how we
> learn...
>
> --
> Michael Mohlere
> My EV: http://www.austinev.org/evalbum/296.html
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
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Discussion Starter · #8 ·
I'm going to take a guess that the motor rpm was a bit low. Lower
rpms are great for acceleration (and torque in general) but the motor
amps will be quite a bit higher than the battery amps. The DCP
controllers can cut back for either excess battery amps (MOSFETs
getting hot) or excess motor amps (freewheel diodes getting hot.) Its
around 3500 rpm that the controller can go full on (freewheel diodes
not being used, battery amps equal motor amps) with your foot to the
floor. If your foot is not on the floor the motor amps are higher
than the battery amps. The DCP 450 can dish out up to 625 motor amps,
but not for long.

You should verify the fan is running full tilt before the current
starts being reduced. Its supposed to be the first line of heat
control and current restrictions are the backup plan.

The DCP 600 should have higher continuous current limits. On the
other hand, flooded golf cart batteries shouldn't really hang out at
250 amps for extended periods of time anyway.

Paul Gooch

Michael Mohlere wrote:

> My 1981 rabbit pickup (see sig) has a DCP 450 (Raptor) Controller. I
> couldn't resist the urge to conquer a fairly major hill....according
> to the emeter it was pulling between 200-250 amps all the way up. I
> could tell that the 450 started limiting the amps (going into creep
> mode) on the way up. My questions is this: would upgrading to a 600
> allow me to pull more amps longer, or am I stressing the system way
> too much already by pulling that many amps continuously....I'm sure I
> will get some slap on the wrist responses, but I guess that is how we
> learn...

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Discussion Starter · #9 ·
Paul -

Took your advice and tackled "the hill" with the truck in 2nd gear
going 35 mph the whole way up....no problem. Thanks for the advice!
I received the fuses from mouser in the mail today, so will be putting
the truck back into its original configuration this weekend - should
eliminate the 220 volt charging issue.

Mike

On 10/23/07, Paul <[email protected]> wrote:
> I'm going to take a guess that the motor rpm was a bit low. Lower
> rpms are great for acceleration (and torque in general) but the motor
> amps will be quite a bit higher than the battery amps. The DCP
> controllers can cut back for either excess battery amps (MOSFETs
> getting hot) or excess motor amps (freewheel diodes getting hot.) Its
> around 3500 rpm that the controller can go full on (freewheel diodes
> not being used, battery amps equal motor amps) with your foot to the
> floor. If your foot is not on the floor the motor amps are higher
> than the battery amps. The DCP 450 can dish out up to 625 motor amps,
> but not for long.
>
> You should verify the fan is running full tilt before the current
> starts being reduced. Its supposed to be the first line of heat
> control and current restrictions are the backup plan.
>
> The DCP 600 should have higher continuous current limits. On the
> other hand, flooded golf cart batteries shouldn't really hang out at
> 250 amps for extended periods of time anyway.
>
> Paul Gooch
>
>
Michael Mohlere wrote:
>
> > My 1981 rabbit pickup (see sig) has a DCP 450 (Raptor) Controller. I
> > couldn't resist the urge to conquer a fairly major hill....according
> > to the emeter it was pulling between 200-250 amps all the way up. I
> > could tell that the 450 started limiting the amps (going into creep
> > mode) on the way up. My questions is this: would upgrading to a 600
> > allow me to pull more amps longer, or am I stressing the system way
> > too much already by pulling that many amps continuously....I'm sure I
> > will get some slap on the wrist responses, but I guess that is how we
> > learn...
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


--
Michael Mohlere
My EV: http://www.austinev.org/evalbum/296.html

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