Question

what is line voltage

Answer 1

Depending on the context, line voltage is typically 120VAC

Answer 2

Single phase : line voltage is typically 120 VAC, Two phase : line voltage is typically 240 VAC, Three phase : line voltage is sqrt(3) times the phase voltage(120VAC), each 120 degrees apart, 208 VAC. Off course these as supplied by US power companies, if you construct your own with transformers you will get different results.

Answer 3

Line voltage is the voltage between a pair of terminals . Generally line voltage is 230V

Answer 4

The above assumes a single phase of 115 VAC, not really that much different than 120 VAC, may depend on distance from source