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Something has me a little puzzled and I thought I throw this out there for general thought.
Neil Dutton posted a link which described how the electrical system associated with an engine works; the link was actually automotive but I cannot see how the principles are any different for us. At any rate, the point was that the battery discharges while starting and supplies the current to the starter motor and all other devices until the engine is running and the alternator is rotating at a sufficient RPM. At this point the battery is actually a load and all current utilized everywhere within the system is supplied by the alternator (again, when running at sufficient RPM - changes back at some low RPM).
If I understand this correctly, because electrons break free from the outer valences of their atomic orbits and move at the speed of light, every point of a wire is the same for our purposes (i.e., moving fifteen feet along a wire at speed of light is equivalently being in the same place for our purposes). Thus, it seems to me that if we measure the voltage to ground at any point in the system then the voltage should be whatever the alternator is putting out (again, only concerned with the running RPM situation).
However, we know this is not the case. Again, if I understand it correctly, this is because there are no "perfect" conductors - very material has some resistance. Some materials have very low resistance (conductors); some materials have very high resistance (insulators). I assume we use copper wire because it has low resistance, bends easily, is plentiful and easy to produce, and is resistant to corrosion. My understanding is that marine wire is "tinned" to improve the corrosion resistance.
So wire has some resistance, and so force (voltage) is required for current to flow. Since energy can neither be created nor destroyed, this force is transformed to heat. We know that energy has been transformed because there is a "voltage drop" - if we measure the voltage at one of the wire versus the other end, they are not the same. If we use Google we can find charts and formulas based on Ohm's law and the properties of the materials that tell us how much voltage drop there will be and how much heat will be generated for a particular wire gauge at a particular length.
Finally, my question: what about connectors? No connection can be perfect and must add resistance. Do similar charts and formulas exist for each added connection?
In planning my re-wiring, I used the wire chart for a 3% voltage drop to determine wire gauge and then moved down one AWG (i.e., used the next larger diameter size wire). So, I think I am fine.
I think I have more connections and more wire than is optimal - but, I find masses of wire confusing. I think I am increasing the resistance of the system for the sake of being able to understand where things are going and what they are doing. I think this is negligible, but then it occurred to me that I did not account for the connections.
Neil Dutton posted a link which described how the electrical system associated with an engine works; the link was actually automotive but I cannot see how the principles are any different for us. At any rate, the point was that the battery discharges while starting and supplies the current to the starter motor and all other devices until the engine is running and the alternator is rotating at a sufficient RPM. At this point the battery is actually a load and all current utilized everywhere within the system is supplied by the alternator (again, when running at sufficient RPM - changes back at some low RPM).
If I understand this correctly, because electrons break free from the outer valences of their atomic orbits and move at the speed of light, every point of a wire is the same for our purposes (i.e., moving fifteen feet along a wire at speed of light is equivalently being in the same place for our purposes). Thus, it seems to me that if we measure the voltage to ground at any point in the system then the voltage should be whatever the alternator is putting out (again, only concerned with the running RPM situation).
However, we know this is not the case. Again, if I understand it correctly, this is because there are no "perfect" conductors - very material has some resistance. Some materials have very low resistance (conductors); some materials have very high resistance (insulators). I assume we use copper wire because it has low resistance, bends easily, is plentiful and easy to produce, and is resistant to corrosion. My understanding is that marine wire is "tinned" to improve the corrosion resistance.
So wire has some resistance, and so force (voltage) is required for current to flow. Since energy can neither be created nor destroyed, this force is transformed to heat. We know that energy has been transformed because there is a "voltage drop" - if we measure the voltage at one of the wire versus the other end, they are not the same. If we use Google we can find charts and formulas based on Ohm's law and the properties of the materials that tell us how much voltage drop there will be and how much heat will be generated for a particular wire gauge at a particular length.
Finally, my question: what about connectors? No connection can be perfect and must add resistance. Do similar charts and formulas exist for each added connection?
In planning my re-wiring, I used the wire chart for a 3% voltage drop to determine wire gauge and then moved down one AWG (i.e., used the next larger diameter size wire). So, I think I am fine.
I think I have more connections and more wire than is optimal - but, I find masses of wire confusing. I think I am increasing the resistance of the system for the sake of being able to understand where things are going and what they are doing. I think this is negligible, but then it occurred to me that I did not account for the connections.
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