I need some help- circuit breaker question 6V vs 12V

[Chris]

Originally Posted by Frank Miller

You're close. Volts x Current = watts. A 58 watt bulb requires 8amps at 6 volts. But 4 amps at 12 volts. The filament will have a higher resistance on the 12 volt bulb to limit the amps. Everyone else is right in that the circuit breakers only see current and do not care about voltage as there is no resistance until they surpass the current rating. At that point the bimetalic strip will curl from the heat and open the circuit. The two metqals have different expansion rates which cause it to curl.

Thank you. Now my question is, if volts make no difference, how come my book list 12V breakers and 24 volt breakers??