why not look around for an old heater, electric stove, or toaster or coffee pot and use that resistance element? >It varies enormously with filament temperature. At 'normal' operation >you can calculate it easily. Assuming it's rated 240V, 500W : >Current is 500/240 = 2.08A, R = V/I = 115R >It may however be a quarter of this when cold. >