EVision

Vehicle Speed

The Simovert provides a motor speed output, 5000Hz at 10000rpm. This can be adjusted by a configurable factor f_out_factor. The EVision & the Simovert share a ground, so this output can be directly connected to the EVision's speed input.

The EVision uses pulses per turn and tyre diameter to calculate road speed. We wish to display motor RPM for now, so we scale for 100km/h (27.78m/s) at 10000rpm.

We make our tyre 2.778 metres in circumference or 2.778/Pi=0.8843m in diameter. This tyre does 10 revolutions per second at 100km/h. We set f_out_factor to 3, now the Simovert outputs 500Hz at 10000rpm, we set out EVision to 50 pulses per revolution.

Wiring

Purpose	EVision harness	CAT 5
PWR	red	white/blue
GND	blue	blue
CAN H	orange	orange
CAN L	black	white/orange
12v +		brown
12v -		white/brown
Speed pulse		green
		white/green

Fuses

The EVision is connected to the pack by 3 wires, these need 50mA fuses. My options seem quite limited here. After quite a lot of searching I found the Bussman FWH-.500A6F which is UL Rated to 500V DC. At US$18 each I'm not so happy. Can be had cheaper at Online Components. (wrong current). Can probably use http://jaycar.co.nz/productView.asp?ID=SZ2014 with a lower voltage pack.

10000 RPM Data Acquisition

Note, this was taken with the shunt incorrectly configured, double all the current readings

grep \\\$IV 10000rpm.csv |cut -d , -f 4- |tr , " " >data.dat
gnuplot
set terminal png
set output "10000rpm-1.png"
plot "data.dat" using 1:2 title "voltage", "data.dat" using 1:4 title "charge current", "data.dat" using 1:5 title "discharge current"
set output "10000rpm-2.png"
plot "data.dat" using 1:6 title "power"