Electric Race Car: What Gauge Wire & Fuse/Circuit Breaker?

• james138698
In summary, the best gauge wire for your human sized electric race car would be AWG10, as it can handle the current and voltage requirements without excessive losses. It is also recommended to use a type B1 terminal to connect the wire to your HR22-12 batteries and to use a fuse or circuit breaker for safety purposes. You can find the necessary materials locally in Tampa, FL.

james138698

I am in the process of building an human sized electric race car, and am wondering what gauge wire would best benefit me.

The car will be powered by 5 HR22-12, data sheet attached, batteries in series running at 12 V 20AH each for a total of 60V 20AH. This is an endurance race lasting one hour. Based on this time frame and the battery profile, these batteries should be able to supply somewhere between 12 and 20 amps.

I am wondering what gauge wire would I be able to use, so as to not burn out the wire or have excessive losses from to large a wire.

Also these races require the use of a fuse or circuit breaker. I am wondering which would be the best option for me.

The HR22-12 have a type B1 terminal. I am wondering what is the best way to connect the terminals with the cable.

I am located in Tampa FL, and am looking to get the cabling and fuse/circuit breaker locally.

I greatly appreciate any help given.

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james138698 said:
I am wondering what gauge wire would I be able to use, so as to not burn out the wire or have excessive losses from to large a wire.
While you wait for a more concrete answer to your query, let me help you along with the basics:

Any loss in the wire will be due to the ohmic resistance, R, in ohms

R = ρL/A

where ρ is the resistivity of the material (for copper, ρ = 1.724 x 10-8 Ωm at room temperature), L is the length in meters, and A is the wire cross-sectional area in m2.

If you know how long your wire needs to be, you can calculate the loss P = I2R in that wire segment. For example, a 2 meter long AWG10 (diameter = 0.1019 in = 0.259 cm = 0.00259 m) copper wire would have a resistance of

R = 1.724 x 10-8 Ωm x 2 m / (0.001295 m2) = 6.5 mΩ

The loss (in the form of heat) due to a current of 20A through that wire would then be

P = (20A)2 x 6.5mΩ = 2.6 W

Or, in terms of voltage that would equivalent with a voltage drop over that wire segment:

V = IR = 20A x 6.5mΩ = 0.13V

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1. What gauge wire should be used for an electric race car?

The gauge wire used for an electric race car will depend on the specific power requirements and electrical components of the vehicle. In general, it is recommended to use a wire gauge that can handle at least 125% of the maximum expected current. This is typically between 6-10 gauge wire for most electric race cars.

2. How do I determine the appropriate fuse or circuit breaker for an electric race car?

The fuse or circuit breaker for an electric race car should be chosen based on the maximum current the vehicle will draw. It is important to select a fuse or circuit breaker with a rating that is slightly higher than the expected maximum current to allow for any unexpected spikes. Consult a professional or refer to the manual for your specific vehicle to determine the appropriate fuse or circuit breaker.

3. Can I use a higher gauge wire than recommended for my electric race car?

It is generally not recommended to use a higher gauge wire than what is recommended for your electric race car. This can lead to inefficiency and potential overheating of the wire, which can cause damage to the vehicle and potentially be dangerous. It is best to stick to the recommended wire gauge for optimal performance and safety.

4. Is it necessary to use a fuse or circuit breaker for an electric race car?

Yes, it is necessary to use a fuse or circuit breaker for an electric race car. These components act as safety measures to protect the vehicle from any electrical faults or overloads. They help prevent damage to the vehicle and potential hazards for the driver and others on the track.

5. Can I use the same wire gauge for all electrical components in an electric race car?

No, it is not recommended to use the same wire gauge for all electrical components in an electric race car. Different components may have different power requirements and it is important to use the appropriate wire gauge for each one. This will ensure optimal performance and safety for the vehicle.