Hi All,
I have a basic question on Electrical wiring. I've been setting up a small electronics lab at my home. Unfortunately, there aren't any electrical outlets at the place. So I set out to do the electrical wiring myself. My requirements were fairly simple. Enough outlets for a desktop PC, Laptop, an oscilloscope, a power supply, Few outlets for soldering station, lighting etc. I calculated that the maximum power drawn shouldn't exceed ~1.2KW (230V 50Hz here).
While doing the wiring, i ended up buying a 70m spool of 1Sqmm multicore (~19 strand ??) local brand wiring. I didn't see any safety certifications or labels. I completed the wiring and connected all the outlets. At the end I checked for shorts between line/neutral and ground, everything was fine. Then for some reason I decided to check the resistance. I was surprised to see 2ohms for the roundtrip length of 20M on Line and neutral
. The total length of the wiring is ~10M. That would mean, if i'm pulling the estimated 1.2KW through the wires, I'd be dissipating a 54W in the wires alone!!!
This seems far too much. Not to mention the fire hazard.
I compared the resistivity datasheets for well known branded cables and they specify ~20 ohms/km for 1sqmm multistrand cables. Compared to that, the ones I've got have about 5 times resistance for the same length.
The question I have now is, Should I rip out all the wiring and redo with branded cables. Are there any other options? How should I size the wires for the application I have.
Also, why do all the sizing suggestions for cables only talk about current capacity alone? Shouldn't the length of the cables also be considered?
Thanks,