Continuously measure isolation resistance between the tractive system and the chassis, and open the shutdown circuit if it falls below the rules threshold.
A rules-required device wired into the safety shutdown chain. A loss of isolation means the high voltage system is finding a path to the chassis, which is the failure mode the whole EV ruleset is built to prevent.
No part-specific design process is documented. The Accumulator LV subsystem design process applies: 1. List every low voltage function inside the container and what it must interface with. 2. Decide grounding architecture (star chosen) and lay out the returns. 3. Design the boards, with conformal coating selected against the requirement (acrylic is easier to rework, silicone is more vibration resistant and more temperature tolerant but costs more and is harder to remove). 4. Design HV monitoring: optocoupler (smaller, cheaper, digital, needs conformal coating) against voltage transducer (no conformal coating needed, larger, more expensive, analog). 5. Build the sub-harnesses, test in simulated conditions before the pack is live.
None recorded. This part has no entry in Knowledge_Transfer/Issue Logging/Fault Vault.xlsx, in either Issue Log.xlsx, in CR22/Issue Tracking/Shakedown 7-15-23.xlsx, or in any design review issue list found in CrimsonStorage or Box.
Nothing in CrimsonStorage covers these yet.