Amprobe LM-120 light meter instruction manual.
The LM-120 light meter provides quick, one‑hand operation for measuring visible light from fluorescent, metal‑halide, high‑pressure sodium or incandescent sources. It displays readings in lux or foot‑candles, offers auto‑ranging, manual ranging, zero‑function, data‑hold, and min/max tracking on a large 3‑digit LCD.
Key specifications include a measurement range of 20 – 200,000 lux (0 – 20,000 fc), 0.01 fc/lux resolution, ±3 % accuracy (calibrated) and ±6 % for other sources, 2.5 measurements per second, and a battery life of about 200 hours with an auto power‑off after roughly 6 minutes. The unit operates from –10 °C to 50 °C, weighs 220 g, and meets CE and EMC directives.
| Measurement range | 20 – 200,000 Lux (0 – 20,000 fc) |
|---|---|
| Resolution | 0.01 fc/lux |
| Accuracy | ±3 % (calibrated), ±6 % other sources |
| Measurement rate | 2.5 times per second |
| Display | 3‑digit LCD, max reading 1999 |
| Power supply | 9 V NEDA 1604 battery |
| Battery life | 200 hours |
| Auto Power Off | ≈ 6 minutes |
| Dimensions (Base) | 130 × 63 × 38 mm |
| Operating temperature | -10 °C to 50 °C |
| Sensor type | Silicon photodiode and filter |
It measures illumination from 20 Lux up to 200,000 Lux (0 – 20,000 foot‑candles).
The battery provides about 200 hours of operation.
Yes, it automatically powers off after approximately 6 minutes of inactivity.
The meter is accurate to ±3 % when calibrated to a standard incandescent lamp and ±6 % for other visible light sources.