The HE lite switches off automatically after 30 seconds, if no button was pressed in the meantime. The display has four lines. In the last line the current function of
the buttons is indicated in white letters on black back- ground. In the picture on the right, arrow to the left, measure and off.
The instrument is equipped with three operational but- tons. The arrow keys and the On/Off-button have additionally the function indicated on the display. The appropriate function is indicated above each button.