Apogee Instruments SP-215 소유자 매뉴얼 - 페이지 18

{카테고리_이름} Apogee Instruments SP-215에 대한 소유자 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Apogee Instruments SP-215 20 페이지. Pyranometer

Independent Verification of Functionality

Apogee SP-200 series pyranometers provide an amplified voltage output that is proportional to incident total

shortwave radiation. A quick and easy check of sensor functionality can be determined using a DC power supply

and a voltmeter. Power the sensor with a DC voltage by connecting the positive voltage signal to the red wire from

the sensor and the negative (or common) to the black wire from the sensor. Use the voltmeter to measure across

the white wire (output signal) and black wire. Direct the sensor head toward a light source and verify the sensor

provides a signal. Increase and decrease the distance from the sensor head to the light source to verify that the

signal changes proportionally (decreasing signal with increasing distance and increasing signal with decreasing

distance). Blocking all radiation from the sensor should force the sensor signal to zero.

Compatible Measurement Devices (Dataloggers/Controllers/Meters)

Serial Number Range 0-10516. SP-200 series pyranometers are calibrated with a standard calibration factor of 0.5

-2

W m

per mV (SP-212) or 0.25 W m

-2

, respectively. Thus, a compatible measurement device (e.g., datalogger or controller) should have resolution of

at least 2 mV, in order to provide shortwave radiation resolution of 1 W m

Serial Numbers 10517 and above. SP-200 series pyranometers are calibrated with a standard calibration factor of

-2

0.8 W m

per mV (SP-212) or 0.4 W m

-2

W m

, respectively. Thus, a compatible measurement device (e.g., datalogger or controller) should have resolution

of at least 1.25 mV, in order to provide shortwave radiation resolution of 1 W m

Effect of Cable Length

When the sensor is connected to a measurement device with high input impedance, sensor output signals are not

changed by shortening the cable or splicing on additional cable in the field. Tests have shown that if the input

impedance of the measurements device is 1 mega-ohm or higher then there is negligible effect on the

pyranometer calibration, even after adding up to 100 m of cable. Apogee model SP series pyranometers use

shielded, twisted pair cable, which minimizes electromagnetic interference. This is particularly important for long

lead lengths in electromagnetically noisy environments.

Modifying Cable Length

See Apogee webpage for details on how to extend sensor cable length

(http://www.apogeeinstruments.com/how-to-make-a-weatherproof-cable-splice/).

-2

per mV (SP-215), yielding a sensitivity of 2.0 mV per W m

-2

per mV (SP-215), yielding a sensitivity of 1.25 mV per W m

-2

or 4.0 mV per W

-2

or 2.5 mV per