Provide a single series chain that de-energises the tractive system if any safety device opens.
Every shutdown device is wired in series: shutdown buttons, inertia switch, brake plausibility device, insulation monitoring device and the BMS fault output. Opening the chain anywhere drops the accumulator isolation relays.
No part-specific design process is documented. The Tractive System subsystem design process applies: 1. Select the motor against the available options. EMRAX is effectively the only viable choice for a non-in-hub design; the 228 LV+43% keeps the 111 kW peak power of the 228 MV at a lower maximum operating voltage. 2. Select the controller against the motor. The PM100DX was chosen first, then discontinued; the recommended CM200DX was lighter and more powerful, but Cascadia does not support the EMRAX custom windings, which is what moved the team to the DTI HV-550 (30-800 VDC, 280 A max input, 320 kW max output, 95% efficiency, 6.8 kg). 3. Draw the tractive system diagram and the interlock chain, then place every component against it. 4. Choose cable and insulation for routing as well as rating. CoreFlex HV cable was chosen because it is far more flexible than standard HV wire, making routing inside the accumulator easier and cleaner, with thick insulation that helps at scrutineering. Nomex YT510 was chosen for safety barriers inside the container. 5. Bench test the shutdown chain before the pack is live.
Board manufactured externally, populated and bench tested in house before it goes on the car.
Custom PCB with a machined or 3D printed enclosure.
Contactors do not provide reliable state feedback. Without it the tractive system could remain energised while the shutdown circuit believes it is off. Mechanical wear or bounce can give inconsistent readings on budget contactors. Adding contactor AUX feedback is the identified fix and is needed to pass the tractive system master switch safety checks.
Nothing in CrimsonStorage covers these yet.