Restricted range selection for electrical multimeter - has range cover plate with stops limiting range knob rotation

摘要

The electric multimeter has a range switch which registers against inscriptions for the parameter and sensitivity being measured. A cover plate allows only the required ranges to be displayed while stops limit knob rotation. A multimeter (1) has a front face (2) on which a pointer (3) moves over a graduated scale. A knob (4) with an operating bar (5) has a pointer (6) to indicate the range in use. A plate (9) has an opening to accept the knob skirt (7) and has a transparent segment for the required parameter ranges (8) with an opaque area (10) to cover the remaining ranges. Two stops (11, 12) in the plate operate in conjunction with a protruding head (13) on the knob to define its angular rotation.