per http://en.wikipedia.org/wiki/American_wire_gauge, 18 AWG has 20.95 Ω/km. 600'=183m=0.183km. 20.95 Ω/km *0.183 km = 3.834Ω.
You can run it as far as you want, knowing that the farther you go, the more voltage drop will occur under load. If you have a very small load, you can run 14 AWG for hundreds of feet.For instance, 14 AWG copper THHN 90C in conduit with 3 percent voltage drop would get you over 600 feet at 1 amp, but only about 50 feet at 15 amps.
This is a voltage drop question. A 500 MCM copper or 750 MCM aluminium conductor will limit the voltage drop to 3% or less when supplying 300 amps for 500 feet on a 240 volt system. Paralleling these conductors will allow the rating to be increased to 600 amps.
600 Volts
Use the general equation for resistance in parallel: 1/R = 1/R1 + 1/R2
A 350 MCM copper conductor with an insulation factor of 75 or 90 degree C is rated at 310 and 325 respectively. So depending on the insulation of the wire that is used, a parallel wire configuration will give you a total of 620 at 75 degrees C or 650 at 90 degrees C.
It is a thermometer using the platinum wire as sensor (resistance thermometer); the resistance of the wire is proportional to the temperature. This type of thermometer is used under 600 0C.
It is: 600 square feet
Assuming the allowed volt drop is 5% or 5.5 volts, the wire resistance has to be 5.5/15 ohms or less, 0.367 ohms. The total length of wire is 600 metres so the resistance per metre is 0.00061 ohms. 1 sq-mm copper wire has a resistance of 0.0168 ohms/metre so you need wire with a size of 0.0168/0.00061 sq-mm, or 27.5 sq-mm. The next size up is 35 sq-mm in European cable size, or #2 AWG in America.
1). You don't need the voltage 'E' in order to calculate the total resistance. The totalresistance is the same whether the circuit is connected to a big battery, to a smallbattery, to a bicycle pump, or lying in the back of the desk drawer.2). In a series circuit, the total resistance is just the sum of the individual resistances.In this example, the total resistance isR1 + R2 + R3 = 100 + 500 + 600 = 1,200 ohms .
You have a 3000 watt load at 300 ft from the power source. Assuming a 240 volt supply voltage, the current is 12.5 amps. The voltage drop should be 5% or 12 volts, so the total resistance should be 1 ohm or less. With 600 ft of wire (2 wires) the allowable resistance per foot is 1/600 ohms, or 0.0047 ohms per metre. A 1 sq.mm. wire has a resistance of 0.0168 ohms/metres, so you need wire of 0.0168/0.0047 sq.mm., that is 3.57 sq.mm. Use wire with a cross section of 4 sq.mm. That is 11 AWG or 13 SWG. If these sizes are unavailable, use the next larger size (smaller gauge number).
600 meters = 1,968.50394 feet
To convert from feet to meters multiply by 0.3048 600 feet = 600 x 0.3048 meters
There are 5280 feet in one mile. Therefore, 1 mile 600 feet is equal to 5280 + 600 = 5880 feet.
There are 182.88 meters in 600 feet.
600*5280=3,168,000 feet
600 millimeters = about 2 feet.
600 feet = 182.88 meters.