PASCO PS-2149 UVA Light Sensor - Manual (Page 3)

Model No. PS-2149 UVA Light Sensor
3 ®
A UV light source is required to perform certain
experiments and demonstrations with the UVA
Light Sensor. The use of a source that radiates
only in the UVA band is recommended because
it is the least hazardous UV radiation. A small
fluorescent “black” light makes a suitable UVA
source.
Other sources of UVA radiation are:
• the sun (best on clear days - but some UV
when overcast)
• sun lamps for tanning
• halogen lamps which are not “UV-protected”
• fluorescent lamps
Operation
Setting up the Sensor
Connect the UVA Light Sensor to the PASPORT
interface. If you will use a computer, connect the
PASPORT interface to the computer and launch
DataStudio.
Selecting the Gain Setting
The sensor has three gain settings depicted by
Candle, Lamp and Sun symbols. These symbols
correspond to three ranges, which cover over 7
orders of relative magnitude. The ranges, in
relative units, and the approximate maximum
(without filter) for each range are:
The ranges are scaled so that a reading of 50 in
the Lamp range will also be read as 50 in the Sun
range. To ensure the maximum resolution, select
the range that will cover the expected
measurements without topping out.
Using the Filter With Retaining Cap
The UVA Light Sensor is shipped with the filter
installed in the retaining cap. When the filter is
removed from the retaining cap, the sensor can
detect light in a wider range of wavelengths. To
remove the filter, unscrew the retaining cap from
the photodiode assembly. Be careful not to
damage the filter.
Using the Filter With the Collimator
With the collimator installed, the sensor detects
light only from sources in a narrow angle.
Remove the retaining cap and replace it with the
collimator.
The filter is designed for use under conditions
where there is not a significant amount of
infrared radiation present; for instance, as part of
a spectrometer. If it is necessary to filter out IR
radiation, use the 365nm Filter Accessory
(CI-9841).
Mounting on an Experimental Apparatus
The sensor handle screws into the 1
⁄4-20
threaded hole on the bottom of the sensor
enclosure. You can use the sensor handle or any
1
⁄4-20 screw to secure the sensor to an
experimental apparatus.
Range Approx. Max.
Candle 0–1
70 mW/m 2
Lamp 0–100 7 W/m 2
Sun 0–10 000
700 W/m
2
UV
A
LI
GH
T
PS-2149
retaining cap
1 ⁄4-20 threaded hole
UVA filter
photodiode
assembly