The LI-250A is a portable meter that displays the output from any LI-COR light sensor that has a cable terminated with a BNC connector. It shows instantaneous values or 15-second averages of values from a sensor.
The LI-250A automatically selects a sensitivity range to optimize accuracy and resolution for a given sensor. It provides a wide dynamic range for high-resolution measurements, even in low-light conditions.
LI-250A Features
- 15-second averaging is turned on or off by pressing a single button
- Over 150 hours of operation from a single 9-volt battery
- Automatic shut-off after 20 minutes of inactivity
- O-ring sealed case for weather protection
- Easy-to-enter calibration multipliers make it simple to change between sensors
- Compatible with the LI-190R, LI-191R, LI-192, LI-193, LI-200R, or LI-210R
- Accuracy:
- 25 °C: Typically ± 0.4% of reading ± 3 counts on the least significant digit displayed (all ranges).
- 0 – 55 °C: Typically ± 0.6% of reading ± 3 counts on the least significant digit displayed (all ranges).
- Range Selection: Autoranging (3 ranges).
- Linearity: ± 0.05%.
- Sensors: Designed for type “SA” sensors; type “SB” and “SL” sensors with BNC connectors are also compatible when calconnector or millivolt adapter are removed.
- Sensor Calibration: Each sensor is supplied with a calibration multiplier. Calibration multipliers for two sensors can be stored in memory. Calibration multipliers are entered from the keypad.
- Signal Averaging: Sensor output can be collected and displayed as a 15-second average (approximately 60 readings). Averages are retained on the display in HOLD mode.
- Display: LCD display. Updated every 0.5 seconds in Instantaneous mode.
- Battery Life: 150 hours typical with continuous operation.
- Power Requirement: One 9V Alkaline battery.
- Operating Conditions: 0 to 55 °C, 0 to 95% RH (non-condensing).
- Storage Conditions: -55 to 60 °C, 0 to 95% RH (non-condensing).
- Size: 14 cm × 7.7 cm × 3.8 cm (5.5″ × 3″ x1.5″).
- Weight: 0.26 kg (0.57 lbs).
- Warranty: 1 year parts and labor.
- LI-250A Range and Resolution:
Sensor |
Range |
Resolution |
Quantum |
0-199 µmol s-1 m-2
0-1999
0-19999 |
0.01 µmol s-1 m-2
0.1
1 |
Pyranometer |
0-19 W m-2
0-199
0-1999 |
0.001 W m-2
0.01
0.1 |
Photometric |
0-1999 lux
0-19999 lux
0-199 klux |
0.1 lux
1
0.01 klux |