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
>
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