can i use 18 gauge with 20 volts?

Answer 1

You can use 18ga with a million volts if you want. It's the type of insulation that limits the voltage. The size of the wire limits how much current you can draw.

Answer 2

The wire usually has writing on the outside of the wire insulation stating its voltage rating. If not on the wire it should be on the wire spool. Almost all insulation is good for at least 24 volts. Most insulation used in home wiring is rated for 600 volts.

18 Gage is rated to carry a maximum of 10 amps,
For chassis wiring 18 gage can carry up to 16 amps.

Unless you are wiring your house use stranded wire.


Maximum Amperage
http://www.Xeocities.com/dtmcbride/home_garden/wire.html
Change X to G in above address.
Yahoo will not allow me post with Geocities. Go figure.

ARRL2 Standard for bundled wires
16 gage 13 amps
18 Gage 10 amps
20 Gage 7.5 amps

Chassis Wiring
16 gage 22 amps
18 Gage 16 amps
20 Gage 11 amps

NEC (National Electrical Code)standard
Use for home wiring
WIRE GAUGE AMPERAGE
#14 15 amps
#12 20 amps
#10 30 amps
#8 40 amps
#6 55 amps
#4 100 amps
#1 150 amps
#00 200 amps

Answer 3

That depends on the Amperage... and also the insulation on the wire. Check the link below there is a table that shows max amperage.

Yes, the 20 volts is okay w/ 18 gauge, the amperage is more important.

Answer 4

First: http://www.powerstream.com/Wire_Size.htm
Second: What are you wiring in a computer that takes 20 volts?