Dear friends and followers.
A lot has happened since the last post. I am now a married to the most
wonderful, and understanding, woman in the world, Lisa Wildare. I Love you!
The car is back on the road after changing brushes, brush holder,
installing a fan and limiting the current to the Agni.
After restoring the commutator I installed the brushes and set the timing.
The default timing marks cannot be used and in order to find the new
"zero" I used the following procedure.
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Brush holder with brushes fitted by Joztek.
The cardboard helps during installation. |
1. Attach the brush holder and tighten the screws just so you can move the
brush holder with your hand.
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Brushholder from Jozztek, fitted with screws to aid set timing. |
2. Apply a low and stable voltage, I used 13.8V from a charger with supply
mode.
3. Attach an amp meter to monitor the amps used by the motor.
4. While the motor is spinning, read the amp value and carefully turn the brush
holder in either direction. Find the position were the amp reading is the
lowest, this is our new "zero". Make a mark on the motor and on the
brush holder.
5. Turn the brush holder against the direction in which the motor i spinning.
I turned the holder 1.5mm. See the Agni workshop manual for more info.
6.Tighten the screws on the brush holder CAREFULLY!
Let the motor run for 20 minutes or so before steping on the gas.
After the timing was set and the brushes were run-in it was time for a test
run. I made a configuration change to the Kelly before the first run. Max amp's
was set to 360A. During hard acceleration I could feel the smell of hot brushes
so I backed it down to 300A.
I haven’t had time to work on my water cooling of the Agni but I have a lot off
fans laying around so I decided to make a cooling fan to the motor. There is
not a lot of space left between the Agni and my batteries so I have to put the
fan on top.
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A (D1238B12B9) 12V fan capabel of pushing 5.25m3 of air per minute. |
The fan sounds like an airplane when it's running. The plan
is to use a thermal switch that will control the on/off of the fan. For now
it's hi jacked into the circuit for the lights. I can't hear the fan when
driving.
Air is pushed down in parallel to the Agni's rear plate. As
you all know the Agni sucks air through the backplane and out through the
stainless ring. In order for the air to get into the Agni I put a small piece Plexiglas
in the bottom of the Agni.
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The fan on top and the plexiglas in the bottom. |
When the fan is running and the motor is still air is coming
out under the car. When the Agni starts to spin you can feel that the air flow
under the car gets weaker, the more RPM's on the Agni the more air is used for
cooling. At max RPM almost all of the air from the fan
goes through the Agni.
With the fan installed I hooked up my Ohm-meter to the thermistor
in the Agni and went for a ride. The fan, in combination with lower the amps,
is working fine. The Ohm-meter never goes below 10KOhm when the Agni is
spinning.