Born to be Wired: Page 4 of 6

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Inside this Article

Front Battery Box
Above the drive motor— six T-145 lead-acid batteries and the control box, mounted to the left of the batteries.
Electric GMC Sonoma Pickup Truck
Randy Richmond’s full-electric-powered GMC Sonoma pickup, converted using a commercial kit.
Removing the internal combustion engine
Out with the internal combustion engine.
Empty engine cavity
Lots of room in the engine compartment.
Author and electric pickup truck
Randy Richmond takes his electric truck to auto events to help spread the word on EV practicality and performance.
Inspecting the DC Motor and Transmission
The 100 hp DC motor bolted to the original transmission.
Installing the Electric Motor
Installing the new electric motor and transmission, with room to spare.
Rear Battery Box
In the bed—a custom battery box holds eighteen T-145s.
Electric GMC Sonoma Schematic Diagram
Electric Vehicle Control Box
The control box, with the logic interface mounted on its cover.
Electric Vehicle 240 VAC Plug
The original gasoline filler cap was replaced by a 240 VAC plug.
Front Battery Box
Electric GMC Sonoma Pickup Truck
Removing the internal combustion engine
Empty engine cavity
Author and electric pickup truck
Inspecting the DC Motor and Transmission
Installing the Electric Motor
Rear Battery Box
Electric GMC Sonoma Schematic Diagram
Electric Vehicle Control Box
Electric Vehicle 240 VAC Plug

Under the Hood

In the space once occupied by the air conditioning unit, Richmond installed a 1,500-watt ceramic heater to provide heat for the cab. Securing the piece required Richmond to fabricate a simple mounting plate from sheet metal—an easy-enough task that suited his metal-working skills.

From there, he worked on the power controller and its cooling system—two of the most important components in the electrical system. The pulse-width-modulated (PWM) power controller regulates the power to the vehicle’s drive train by translating the position of the accelerator pedal into power flowing to the electric motor, making the car go.

For every amp that flows to the motor from the controller, 2 watts of waste heat are generated in the controller. At 400 amps, for example, the power controller produces 800 watts of heat. The cooling system circulates water through the controller to cool the electronics, preventing the unit from overheating and causing a thermal shutdown of the Zilla controller.

Outfitting the Cab

With these vital components in place, and after mounting the vacuum pump for the power brakes, the control box, and the remaining battery box above the electric motor, Richmond moved his work from under the hood into the cab. There, he mounted the charger and 45 A DC-DC converter behind the driver’s seat. The extended cab allowed enough room for both components, which should not be exposed to the elements. As an added bonus, the charger produces heat while charging. “When it’s colder outside, I try to charge the truck right before I leave for work. That way I don’t have to run the heater as much, if at all,” Richmond says. 

The DC-DC converter charges a 12-volt battery (also in the cab) that powers the vehicle’s accessories—headlights, windshield wipers, radio, etc. This battery is separate from the traction batteries under the hood and in the bed so that the vehicle can operate standard 12 V accessories independently.

Richmond wrapped up the cab components installation by installing a battery SOC meter—what he considers an “absolute must” for EV newbies who tend to overestimate their battery charge. Much like a gas gauge shows the amount of gas in the tank, the SOC meter shows the amount of energy available in the vehicle’s batteries.

Tying up Loose Ends

One of his final tasks—wiring the AC power cabling to the charger—was perhaps the easiest. The AC plug fit perfectly behind the old gasoline filler cap, saving Richmond from enlarging the existing hole. 

Last but certainly not least was wiring the three-fold safety system and wiring the batteries to each other. The EV’s safety system includes a 500 A fuse in the rear battery box that opens the circuit if the system shorts; a breaker in the control box that is connected to a knob on the dash board for emergency disconnect; and an inertia switch in the control box that causes the circuit to open and stop the motor in the event of an accident. Wiring the batteries seems fairly straightforward—connecting the positive terminal of one battery to the negative of the next—but tight connections are vital to performance and preventing the connections from overheating and melting the terminals.

Turning the Key

Then came the moment he had anticipated for more than a year—the test drive. “It’s a nerve-racking moment. You just hope that everything works and no smoke appears,” he recalls.

Rather than running the motor at the full 400 amps, he took gradual steps. Using his laptop connected to the controller’s computer interface, he programmed the power controller for 50 amps—barely enough power to move the vehicle. He adjusted the settings eight times, adding 50 amps each time until reaching the maximum, 400 amps. At each increment, he checked all the components and connections for signs of heat and unusual noises.

Comments (6)

jerryd's picture

I'd suggest anyone wanting to convert and EV start with the lightest one they can find as EV's cost by the lb of the donor vehicle. So if you start with a 2-3k lb vehicle and strip it down by about 1/3 the weight you need a smaller battery pack, motor, controller for the same range, performance.

Doing things like low rolling resistance tires, making aero improvements, low drag diff, transmission oils, etc can nicely increase range. So start light and aero for a cost effective EV.

Kienan Maxfield's picture

If you would like to regain your A.M. radio reception, just find the wire powering your radio and wire in a couple capacitors and a couple of good inductors. For a diagram on how to wire it, click the following link or copy and paste the following address into your browser.

https://dl.dropbox.com/u/8017159/DC... — or —

http://db.tt/lWq7JEFg

Kienan Maxfield's picture

I realized this would not work because the problem has to do with emitted RF rather than the supplied power. This would only work for pulsing load or pulsing charge related interferences such as alternator whine.

willwilkin@madeinusasolar.us's picture

I'm limping my gasoline-powered Ranger for a few more years till I can get the money for an electric pick-up that I will charge by solar PV. Hopefully EV pickups will become available soon. I am not going to build it myself, but admire those who do!

CasaDelGato's picture

More electric trucks! yeah!
http://john.casadelgato.com/Electri...

RG B's picture

Nice work

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