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Do I understand your question correctly that you want your Emus BMS to intervene by not allowing a throttle signal to get to the controller rather than opening a main contactor?

Perhaps it is possible, but would not do it myself. What if someone is driving, the BMS intervenes and to the controller it looks like the throttle is not pressed at all and the current drops. Problem no longer triggering that intervention (if for example the reason was low voltage error due to voltage sag).
In the meantime, the driver is confused due to no throttle response and plays around and floors the pedal. An in that moment the BMS resumes the throttle signal to the VCU..... bad things can happen.
And at the same time: if the error is caused by low SOC or high temperature, the controller current drops to zero but how about power used by the dc/dc and heater?
Personally I prefer a BMS to be in control of a pack being “online” and thus have the ability to open contactors during errors.
A safety plus is that you will need to restart and go through precharge again (assuming the bms goes out of drive mode and into ready mode after having opened a contactor.
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