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Hi, I'm working on a new 24v car and I have a question for you all. I need to have a resetable circuit breaker set to 100amps so if i were to buy a 12v 100amp circuit breaker would it be like having a 50amp circuit breaker OR would it still cut out at 100amps??
I should know this but I'm not entirely sure. As far as I remember current is proportional to voltage so yes it should, although it would depend on the resistance and oh no were did all my memory go?
Murphy's 9th Law of Technology:
Tell a man there are 300 million stars in the universe and he'll believe you. Tell him a bench has wet paint on it and he'll have to touch to be sure.
i know what you mean i've helped to build several electric race cars and i don't know i've also asked people from other teams and they don't know either! so if anyone can help me come to a difinitive answer please help!
Greenpower Electric Car Races for Schools has 24 volt 100 amp circuit breakers. 17.16 including VAT. Just Google "24 volt 100amp circuitbreaker for electric car" and the first entry is the Greenpower sales site. Although someone explained how to link - I still don't get it - I still can't do it
100 amps is 100 amps, since you'd be running 24 volts trough 12 volt circuit breaker, circuit breakers itself would probably overheat and cut not because some part of the system reached 100 amps but because it can't transmit 24 volts trough itself.
That's just my opinion, wait to get answer from professional.
thanks carlos however if you read the description i belive it describes a 70amp version they no longer stock 100 amp circuit breakers. I enquired before a race at the top gear test track last year so I had to make do with 120 but thts too high for my liking and they have also now been outlawed.
Good point MC im sure there is someone on here that will know.
Amperage is a measure of volume. In fact, 1 Amp = 6.242x10 18 electrons per second. Voltage is defined as electrical pressure. I like to use the analogy of a water hose. The water volume flowing through the hose is amperage, and the pressure is voltage. The actual hose holding the water under pressure is like the insulation holding the voltage from escaping.
Roughly speaking, power (watts) is calculated by multiplying the voltage and amperage. One horsepower is 746 watts. Since you are pushing 100 amps with 24 volts, (100 x 24 divided by 746), we're looking at 3.22 HP.
Most fuses/circuit breakers function by overheating an element, which trips or fails at the designed limit. And that's the problem, because the voltage is half of what the breaker was designed for. Most likely, it will not trip out at 100 amps, you are outside the design parameters of the circuit breaker/fuse.
I strongly suggest you don't take the easy route but instead go to the bother of hunting down a fuse designed to fail at the specified voltage and amperage. Additionally, a circuit breaker is designed to open at it's set value once, just the first time. After that, all bets are off there is no guarantee that after it is re-set that it will open at exactly 100 amps. It may be 97, or 120, or whatever. Circuit breakers are convenient, but fuses are foolproof.
excellent, thank you very much i shall do my best to find a 100amp 24v but it really isn't easy, the rules require that as a maximum some teams hardwire it illegally some use 70amps in the formula with 240watt motor instead of the 600watt motor required for my formula so I think a 100amp trip switch would be a better bet.
