Yes it is normal depends on what watts you have it set on. Try setting it a bit higher. Or,
If you have a Joyetech Evic Vtc Mini or Aspire Nx75 you can now set the preheat temp to a higher wattage for however many seconds that you need for ramp up then it defaults to the preset temp.
At .28 ohm start @ 40 watts & go up from there until you feel there is hardly any ramp up.I only have a eleaf istick pico 75w and a wismec rx 2/3
How high on watt can i go? My mod is reading 0.28ohm