Different Wattage

I have a 30 watt fan. When I run it using my AC180, it runs at 24 watts. When I run it using my EB3A, it runs at 44 watts! Why is this? Just curious.

The EB3A cant measure watt it measures current and multiply it with 230 or 120

Right, the meassurement fro the EB3A isnt really precise, its more like a estimation.