Fleabag, the voltage drop when a load is present is NOT because of INCREASED resistance in the wires as load increases - the resistance does not change. However, the voltage drop IS because of that (constant) resistance and the current flowing through the load. The voltage drop, Delta V = IR, where I is current and R is wiring resistance.
Now, the resistance of all the wiring supplying the house, up to the breaker for the individual circuit, is generally very low. It is designed so that, even at maximum total current (for the whole house) allowed by the main breaker, the voltage at the individual breaker inputs on the bus in the panel is still very close to nominal supply voltage. Similarly, the 14-gauge wires specified for each branch circuit will deliver very little undervoltage to each outlet on that circuit up to its 15 amp capacity. I did say "very little" - like, a few volts drop at full 15 amps - but not zero drop. So although the combined effect of these is that the voltage available at the outlet may be a few volts lower than the spec of 120 V AC, the major voltage drop is likely to be in the 100-foot-long extension cord plugged into that outlet to reach the leaf blower. If the cord is 12-gauge as dullard recommends, its lower (fixed) resistance makes the voltage drop across it smaller and more tolerable.
Yes, the voltage drop across the extension cord is only one of at least three sources of drop in the system. But everything up to the wall outlet is basically beyond the user's control, and has already been designed and built, compelled by law and regulations, to provide adequate voltage up to the outlet. However, the extension cord is NOT rigidly regulated so that users can make a bad decision. Education such as this discussion are one way to encourage good choices.
Now, the resistance of all the wiring supplying the house, up to the breaker for the individual circuit, is generally very low. It is designed so that, even at maximum total current (for the whole house) allowed by the main breaker, the voltage at the individual breaker inputs on the bus in the panel is still very close to nominal supply voltage. Similarly, the 14-gauge wires specified for each branch circuit will deliver very little undervoltage to each outlet on that circuit up to its 15 amp capacity. I did say "very little" - like, a few volts drop at full 15 amps - but not zero drop. So although the combined effect of these is that the voltage available at the outlet may be a few volts lower than the spec of 120 V AC, the major voltage drop is likely to be in the 100-foot-long extension cord plugged into that outlet to reach the leaf blower. If the cord is 12-gauge as dullard recommends, its lower (fixed) resistance makes the voltage drop across it smaller and more tolerable.
Yes, the voltage drop across the extension cord is only one of at least three sources of drop in the system. But everything up to the wall outlet is basically beyond the user's control, and has already been designed and built, compelled by law and regulations, to provide adequate voltage up to the outlet. However, the extension cord is NOT rigidly regulated so that users can make a bad decision. Education such as this discussion are one way to encourage good choices.
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