Direct Digital Readout: Instantaneous sensor output or
15-second averages can be shown on the LI-250A's display. Measurement units
for any LI-COR sensor (µmol, lux, klux, or W m-2) are also displayed.
High Quality Circuitry: The high quality amplifier in the
LI-250A provides excellent long-term stability and automatic zeroing. This
high gain amplifier gives very low input impedance to sensors, resulting in
excellent linearity. Typical accuracy is 0.4% of reading at 25 °C.
Automatic Range Selection: The LI-250A simplifies
operation by automatically selecting the range with the best accuracy and
resolution for a given sensor input signal. The wide dynamic range allows
measurements in a wide variety of light environments.
Hold Key: Pressing the HOLD key lets you retain the
current reading on the display. Pressing the HOLD key again returns the
LI-250A to measurement mode where the display is continuously updated.
Average Key: 15-second averages can be collected and then
held on the display by pressing the AVG key.
Hand-held, Battery Operated: The LI-250A's low power
consumption gives you more than 150 hours of operation from a single 9-volt
transistor battery. To conserve battery life, the meter auto-matically shuts
off after 20 minutes of inactivity.
Weathertight: The LI-250A case is O-ring sealed to make it
Sensor Calibration: Calibration multipliers for LI-COR
sensors can be entered by simply pressing the CAL key, setting the display
units (UNITS key), and then changing the sensor calibration multiplier with
the up and down arrow keys. Two sensor multipliers can be held in memory to
aid in switching between sensors.
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: 4 1/2 digit LCD display. Updated every 0.5
seconds in Instantaneous mode.
Keypad: Sealed, 5-key tactile response keypad.
Battery Life: 150 hours typical with continuous operation.
Power Requirement: One 9V Alkaline battery.
Low Battery Detection: Low battery indicator displayed
with approximately 20 hours battery life remaining.
Operating Conditions: 0 to 55 °C, 0 to 95% RH
Storage Conditions: -55 to 60 °C, 0 to 95% RH
Size: 14 cm L x 7.7 cm W x 3.8 cm D (5.5" x 3"
Weight: 0.26 kg (0.57 lbs).
Warranty: 1 year parts and labor.
LI-250A Range and Resolution
||199 µmol s-1 m-2
|0.01 µmol s-1 m-2
||19 W m-2
|0.001 W m-2
Battery included. Order sensors separately.
250-01 Carrying Case
216 Replacement Battery. 9 volt transistor type.
Requires 1 for replacement.
Solar irradiance measurements for meteorological, hydrological and
environmental research can be made using the LI-200 Pyranometer Sensor. The
LI-200 measures global solar radiation (sun plus sky) and provides a typical
accuracy of ±5% under unobstructed daylight conditions.
LI-250A Light Meter with LI-210 Photometric Sensor and 2003S Mounting
and Leveling Fixture.