System Overview

The shutdown control and universal monitoring (SCUM) is the module that is in charge of ensuring rules compliance and safe operation of the vehicle. The primary job is to monitor for faults and open the shutdown circuit when a fault condition is detected. This is broken down into multiple conditions. They are composed of:

• Accumulator management system (AMS)
•  Insulation monitoring device (IMD)
•  Brake system plausibility device (BSPD)

Fault conditions

The AMS fault is triggered by the Orion BMS and is pulled down to ground in the event of a fault eg. overvoltage. The BMS protects the accumlator from fault conditions. (See https://www.orionbms.com/manuals/pdf/orionbms2_wiring_manual.pdf)  

The IMD fault is triggered by the Bender IR155-3204. The IMD detects when there is short circuit between the chassis and high voltage.  

The BSPD fault is triggered by a non-programmable circuit that prevents the driver from braking and accelerate at the same time, in order to prevent failures with stuck throttle pedals. 

Through monitoring these conditions, if the vehicle is entered a fault state, the vehicle can be shutdown safely by opening the shutdown circuit.