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I have convinced myself to dabble in 480v/600v - 120v AC transformers to lessen voltage drop over long distances. I was advised by friend(s) that I should talk to an electrician first but friendly advice hasn't stopped me before and won't start now... I'm pretty sure I can do this correctly and safely without murdering anyone else or myself.
A friend built a structure about 262 Meters (860 Feet) from the Battery & Inverter shelf in the Peopleport, it could use a power feed, and setting up it's own solar power array would require duplicating equipment and unnecessary deforestation.
When it comes to transmitting power, the benefit of higher voltages is that less copper is needed in the form of wire to transmit the same amount of power. As electricity flows across a wire there is some loss, sometimes referred to as "Voltage Drop", this is because wires like everything, have resistance. The thicker the wire, the less the resistance. The higher the voltage, the less impact that resistance has on transmission efficiency.
Transformers have their own loss in conversion, of course... But it is usually pretty small, like 2-3% or so for each transformer.
../pictures/NEC_Recommendation01.png
I'll be using this handy voltage drop calculator for the following examples:
https://www.calculator.net/voltage-drop-calculator.html
A 12awg copper pair of wires going 262 meters, transferring 2400 watts of power (120volts, 20 amps) will lose 59.7VOLTS, or 49.81% voltage drop.... At the end of the conductors the AC voltage would only be 60 volts! Such a system just isn't capable of transferring 2400 watts of power, it could transfer much smaller quantities of electricity but I'm going to consider 2400 watts a minimum.
In order for an acceptable level of voltage drop transferring 2400 watts (120volts, 20amps) 1awg copper wire would need to be used. 1awg wire is about 2.77 per foot. (860x2)x2.77 = $4764, not good.
2400 watts (600volts, 4 amps) over 12awg wire = 1.99% Voltage drop
Still losing ~12 volts, which would be substantial on a 120v circuit, but on a 600v circuit it is neglegible.
I could even use cheaper 14awg wire, and only get 3% voltage drop (18.4 volts loss)
12awg = ~$0.21/ft | (860x2)x0.21 = $361
14awg = ~$0.14/ft | (860x2)x0.14 = $240
Seems worth it to spend on 100-200$ worth of transformers to save the thousands on the 1awg cable
Checking Ebay I got the cheapest pair of 1000va capacity 600v/120v transformers I could find:
../pictures/EbayTransformer01.png
It has several taps so it can even operate as a 600v/480v/240v to 120v/100v transformer.
../pictures/EbayTransformer02.jpg
More, and higher VA transformers will be needed in time, but for now this will be sufficient.
It will be possibly a month or longer before I can get this tested/working, but I'll post again on this topic once I have.
