The Amprobe LM-100 light meter measures the visible light from fluorescent, metal halide, high pressure sodium or incandescent sources. It is a portable, easy-to-use meter designed to allow users to reduce the energy burden of a building by increasing the efficiency of its lighting system. With the LM-100 users can quickly determine the indoor illumination level and adjust the output level of lighting fixtures accordingly.

Amprobe LM-100 light meters display light levels in either Lumen (lux) or footcandle (fc) units. The unit can be selected by a switch on the front panel. The LM-100 has a reliable silicon photodiode sensor and filter and includes ranges up to 20,000 fc or 200,000 lux with an accuracy of ±3% and a resolution of 0.01 fc/lux. This meter is manual ranging. Features of the LM-100 include the ability to zero out the reading before taking a measurement, a data hold feature used to freeze readings on the display, a MIN/MAX function to show high and low readings, and an auto power-off to save battery life.