Nhra Battery Cutoff Switch Wiring In 2023

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NHRA Battery Cutoff Switch Wiring in 2023


In the world of drag racing, safety is of utmost importance. One crucial safety feature is the NHRA battery cutoff switch, which helps to prevent electrical fires and other hazards. In this article, we will guide you through the process of wiring a battery cutoff switch according to NHRA regulations in 2023.

What is an NHRA Battery Cutoff Switch?

An NHRA battery cutoff switch is a device used to disconnect the battery from the electrical system of a vehicle. It is typically installed in the positive battery cable and can be activated externally to completely cut off power to the vehicle. This switch is required in NHRA-sanctioned races to ensure the safety of drivers, crew members, and spectators.

Choosing the Right Battery Cutoff Switch

Before wiring the cutoff switch, it is important to choose the right switch for your vehicle. NHRA regulations specify that the switch should be capable of handling the full load carried by the vehicle’s electrical system. It should also be easily accessible from outside the vehicle and clearly marked with its function. Ensure that the switch meets all NHRA requirements before proceeding with the installation.

Wiring the NHRA Battery Cutoff Switch

1. Start by disconnecting the negative battery cable to prevent any accidental short circuits during the installation process.

2. Determine the location for mounting the cutoff switch. It should be easily accessible from outside the vehicle, preferably on the rear panel or near the rear bumper.

3. Mount the switch securely using the appropriate hardware provided with the switch. Ensure that it is tightly secured to prevent any movement during racing conditions.

4. Connect one end of a heavy-duty battery cable to the positive terminal of the battery. Secure it tightly using a wrench or pliers.

5. Connect the other end of the battery cable to one of the switch terminals labeled “BATTERY.”

6. Connect another heavy-duty battery cable to the remaining switch terminal labeled “ALTERNATOR.”

7. Connect the other end of this cable to the positive terminal of the alternator. Again, ensure that the connection is tight and secure.

8. Reconnect the negative battery cable that was previously disconnected.

Testing the NHRA Battery Cutoff Switch

After completing the wiring process, it is crucial to test the functionality of the battery cutoff switch. With the switch in the “ON” position, start the vehicle and ensure that all electrical systems are functioning properly. Then, activate the switch to the “OFF” position and observe if the vehicle shuts off completely. If the vehicle continues to run or any electrical components remain active, revisit the wiring and ensure all connections are secure.


Wiring an NHRA battery cutoff switch is an essential safety measure for drag racing. By following the NHRA regulations and proper installation procedures, you can ensure the safety of yourself, your vehicle, and everyone around you during races. Always double-check the wiring and functionality of the switch before hitting the track to guarantee a secure and successful racing experience.