Hello, I'm 15 years old and decently active.
My resting pulse rate is an average of 65.
Today I tried out the eliptical machine at my school for the first time, my instructor said to keep my heart rate around 150.
At a comfortable speed, my heart rate would not go under 180.
The machine said my speed was 3.0, which was difficult for me to keep there. It was way easier to keep my speed at around 8.0-9.0. I stayed at that speed for about 20min, my heart rate stayed between 180-195 but I felt perfectly fine, rather good actually.
The machine said for my ages at 80% intensity it should be around 165.
I'm curious if, something is wrong with my heart that it speeds far too much, or if the machine is just reading my pulse wrong.
I'm not a cardiologist or anything, but I'm pretty sure 195 is way too high for moderate exercise.

I skate very often, mountain bike, as well. I also walk a lot on a daily basis. I never really run though, and every now and then I'll get bored and use the eliptical machine in my house, though that one doesn't read pulse or anything at all.