Monday, November 3, 2008

Wiring the 12 Volt System

After surviving a short period of being low on motivation, I finally started wiring up the 12 volt portion of the car. It's good to see the gauges and lights working again. It's like the car is coming back alive.

By the way, this is not your typical 1971 Duster. Besides the digital dash, I have installed my own version of a keyless ignition system. Bringing a specific RFID key fob close to the hidden sensor turns on the 12 volt power (obtained from a small battery). Pushing the button behind the flasher switch energizes the first main contactor and turns on the tiny pilot LED that I mounted in the flasher switch handle. This switch powers up the DC-DC converter which keeps my small 12 volt lawn mower 'system battery' charged off of the 156 volt traction battery pack. It also pre-charges the capacitors in the DC motor controller.

The original ignition switch has been removed. In its place I installed a tiny red momentary pushbutton. This pushbutton will control a set of relays that energize the second main contactor. This switch is pushed when you are ready to travel. For safety, this set of relays will not turn on the contactor unless the accelerator pedal is all the way up, the foot brake is on, and the emergency brake is off.

A small momentary pushbutton mounted behind the ashtray door is the system 'kill switch' that shuts down all 12 volt 'control' power, thus also opening the main contactors. There will also be an emergency 'kill switch' that physically attaches a control wire to the circuit breaker handle. This can be pulled in an emergency to immediately cut off all high voltage/amperage power to the motor and controller from the driver's seat.

No comments: