Embedded Files
Wiring or connectors that are a part of the Tractive System must be properly safeguarded. If these connections are not within the bounds of a housing, alternative protective measures must be applied. These connections must either contain an Interlock which, if interrupted, opens the Shutdown Circuit. These cases are elaborated upon in EV.7.8, and EV.7.2.2 respectively.
Rules Reference - EV.7.8
Rules Reference - EV.7.8
EV.7.8 Interlocks
EV.7.8.1 Interlocks must be incorporated where specified (refer to EV.4.1.3, EV.5.5.2, EV.5.10 )
EV.7.8.2 Additional Interlocks may be included in the Tractive System or components
EV.7.8.3 The Interlock is a wire or connection that must:
a. Open the Shutdown Circuit EV.7.2.2 if the Interlock connection is broken or interrupted
b. Not be in the low (ground) connection to the AIR coils of the Shutdown Circuit
EV.7.8.4 Interlock circuits or connections do not require physical separation (EV.6.5) from Tractive System wiring or components
An Interlock is described in EV.7.8, and a synopsis of its specifications are as follows:
Interlocks must be embedded within the HVD, Tractive System Connectors outside of a housing, and specific cases of Outboard Wheel Motors as per EV.7.8.1, but can be used in additional components not specified as stated in EV.7.8.2.
From EV.7.8.3.a, an Interlock is defined as a wire or connection which, if interrupted, opens the Shutdown Circuit. This connection should be distinct from the ground connection to the Accumulator Isolation Relay Coils, as stated in EV.7.8.3.b. These connections do not require physical separation form the Tractive System Wiring or components (per EV.7.8.4) because they engineered to function effectively without requiring physical separation from high voltage components. They are designed with safety features, efficiency considerations, and compliance with standards in mind to ensure they operate reliably within the electrical system they are meant to protect.
According to EV.7.2.2, opening the Shutdown Circuit requires that components within the Tractive Path must be shut down. Additionally, current flow must stop within the Accumulator and the Accumulator Isolation Relay (AIR) Coils must be engaged. As stated in EV.5.4.3, the Accumulator Isolation Relays are of the Normally Open Type, so in the non-energized state, there should be no High Voltage outside of the Accumulator Container.
Additionally, the Tractive system, within five seconds of the Shutdown Circuit engaging, must be read on a multimeter as Low Voltage, which, stated in T.9.1.2 is defined as DC voltage less than 60V, or AC voltage less than 25VRMS. Finally, torque cannot be applied to slow down or speed up the motor(s).
Rules Reference - EV.7.2.2
Rules Reference - EV.7.2.2
EV.7.2.2 When the Shutdown Circuit Opens:
a. The Tractive System must Shutdown
b. All Accumulator current flow must stop immediately EV.5.4.3
c. The voltage in the Tractive System must be Low Voltage T.9.1.2 in five seconds or less
d. The Motor(s) must spin free. Torque must not be applied to the Motor(s)
Rules Reference - EV.5.4.3 (Referenced in EV.7.2.2)
Rules Reference - EV.5.4.3 (Referenced in EV.7.2.2)
EV.5.4 Accumulator Isolation Relays - AIR
EV.5.4.3 When the AIRs are open, High Voltage T.9.1.1 must not be external of the Accumulator Container
Reference Rule - T.9.1.2 (Referenced in EV.7.2.2)
Reference Rule - T.9.1.2 (Referenced in EV.7.2.2)
T.9.1.2 Low Voltage - LV
Any voltage less than and including 60 V DC or 25 V AC RMS
Rules Reference - IN.4.7.1
Rules Reference - IN.4.7.1
IN.4.7 Electrical Inspection Completion
IN.4.7.1 All or portions of the Tractive System, Charger and other components may be sealed IN.2.6
IN.4.7.1 simply states that teams are allowed to seal portions of the High Voltage (HV) Systems such as the Tractive and Charging Systems. Now, EV.5.10 states that if the connector outside of a Housing is sealed (as made allowable by IN.4.7.1), it is not required to contain an interlock and open the Shutdown Circuit.
Page updated
Report abuse