when my HPWC was first installed I'm sure I got aprox. 50 km/hr on the charger. Now 3 months later I only seem to get 33 km/hr. I've read that if it is 3 phase charging there should be a small 3 in a circle on the display. That is not there, and I can't remember if it was ever there. Does anyone have any suggestions on what may have caused a slow down in the charging rate?