Surface Resistance Meter

The WL MIDGET is an ultra wide range, battery operated, portable instrument for measuring Surface Resistivity and Resistance to Ground of virtually any flat surface conforming to ASTM D-257 standard method by using recommended parallel bar sensing probe. Giving simple repeatable measurements of conductive, static dissipative, and insulative surfaces. Ranging is automatic due to the use of high speed OP-AMP Integrated circuits being linear, with changeover points +1/2 decade on a logarithmic scale. Repeatability equals + 5%.

Operation of the WL Midget

Remove the battery compartment end panel and insert a good quality 9V alkaline battery.  Hold the checker away from any surface and press the test button, the insulative red LED should light.

Place the checker onto the surface that requires testing, again press the test button and hold.  The LED that illuminates constantly is the decade measured.

1                                                                                              Kilohm              (10 ³)     Green LED

10                                                                                             Kilohm              (10 ⁴)     Green LED

100                                                                                           Kilohm              (10 ⁵)     Green LED

1                                                                                              Megohm           (10 ⁶)     Yellow LED

10                                                                                             Megohms         (10 ⁷)     Yellow LED

100                                                                                           Megohms         (10 ⁸)     Yellow LED

1,000                                                                                        Megohms         (10 ⁹)     Yellow LED

10,000                                                                                      Megohms         (10 ¹⁰)    Yellow LED

100,000                                                                         Megohms         (10 ¹¹)    Yellow LED

1,000,000                                                                      Megohms         (10 ¹²)    Red LED